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hyvideo/config.py

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+import argparse
+from .constants import *
+import re
+from .modules.models import HUNYUAN_VIDEO_CONFIG
+
+
+def parse_args(namespace=None):
+    parser = argparse.ArgumentParser(description="HunyuanVideo inference script")
+
+    parser = add_network_args(parser)
+    parser = add_extra_models_args(parser)
+    parser = add_denoise_schedule_args(parser)
+    parser = add_inference_args(parser)
+    parser = add_parallel_args(parser)
+
+    args = parser.parse_args(namespace=namespace)
+    args = sanity_check_args(args)
+
+    return args
+
+
+def add_network_args(parser: argparse.ArgumentParser):
+    group = parser.add_argument_group(title="HunyuanVideo network args")
+
+    # Main model
+    group.add_argument(
+        "--model",
+        type=str,
+        choices=list(HUNYUAN_VIDEO_CONFIG.keys()),
+        default="HYVideo-T/2-cfgdistill",
+    )
+    group.add_argument(
+        "--latent-channels",
+        type=str,
+        default=16,
+        help="Number of latent channels of DiT. If None, it will be determined by `vae`. If provided, "
+        "it still needs to match the latent channels of the VAE model.",
+    )
+    group.add_argument(
+        "--precision",
+        type=str,
+        default="bf16",
+        choices=PRECISIONS,
+        help="Precision mode. Options: fp32, fp16, bf16. Applied to the backbone model and optimizer.",
+    )
+
+    # RoPE
+    group.add_argument(
+        "--rope-theta", type=int, default=256, help="Theta used in RoPE."
+    )
+    return parser
+
+
+def add_extra_models_args(parser: argparse.ArgumentParser):
+    group = parser.add_argument_group(
+        title="Extra models args, including vae, text encoders and tokenizers)"
+    )
+
+    # - VAE
+    group.add_argument(
+        "--vae",
+        type=str,
+        default="884-16c-hy",
+        choices=list(VAE_PATH),
+        help="Name of the VAE model.",
+    )
+    group.add_argument(
+        "--vae-precision",
+        type=str,
+        default="fp16",
+        choices=PRECISIONS,
+        help="Precision mode for the VAE model.",
+    )
+    group.add_argument(
+        "--vae-tiling",
+        action="store_true",
+        help="Enable tiling for the VAE model to save GPU memory.",
+    )
+    group.set_defaults(vae_tiling=True)
+
+    group.add_argument(
+        "--text-encoder",
+        type=str,
+        default="llm",
+        choices=list(TEXT_ENCODER_PATH),
+        help="Name of the text encoder model.",
+    )
+    group.add_argument(
+        "--text-encoder-precision",
+        type=str,
+        default="fp16",
+        choices=PRECISIONS,
+        help="Precision mode for the text encoder model.",
+    )
+    group.add_argument(
+        "--text-states-dim",
+        type=int,
+        default=4096,
+        help="Dimension of the text encoder hidden states.",
+    )
+    group.add_argument(
+        "--text-len", type=int, default=256, help="Maximum length of the text input."
+    )
+    group.add_argument(
+        "--tokenizer",
+        type=str,
+        default="llm",
+        choices=list(TOKENIZER_PATH),
+        help="Name of the tokenizer model.",
+    )
+    group.add_argument(
+        "--prompt-template",
+        type=str,
+        default="dit-llm-encode",
+        choices=PROMPT_TEMPLATE,
+        help="Image prompt template for the decoder-only text encoder model.",
+    )
+    group.add_argument(
+        "--prompt-template-video",
+        type=str,
+        default="dit-llm-encode-video",
+        choices=PROMPT_TEMPLATE,
+        help="Video prompt template for the decoder-only text encoder model.",
+    )
+    group.add_argument(
+        "--hidden-state-skip-layer",
+        type=int,
+        default=2,
+        help="Skip layer for hidden states.",
+    )
+    group.add_argument(
+        "--apply-final-norm",
+        action="store_true",
+        help="Apply final normalization to the used text encoder hidden states.",
+    )
+
+    # - CLIP
+    group.add_argument(
+        "--text-encoder-2",
+        type=str,
+        default="clipL",
+        choices=list(TEXT_ENCODER_PATH),
+        help="Name of the second text encoder model.",
+    )
+    group.add_argument(
+        "--text-encoder-precision-2",
+        type=str,
+        default="fp16",
+        choices=PRECISIONS,
+        help="Precision mode for the second text encoder model.",
+    )
+    group.add_argument(
+        "--text-states-dim-2",
+        type=int,
+        default=768,
+        help="Dimension of the second text encoder hidden states.",
+    )
+    group.add_argument(
+        "--tokenizer-2",
+        type=str,
+        default="clipL",
+        choices=list(TOKENIZER_PATH),
+        help="Name of the second tokenizer model.",
+    )
+    group.add_argument(
+        "--text-len-2",
+        type=int,
+        default=77,
+        help="Maximum length of the second text input.",
+    )
+
+    return parser
+
+
+def add_denoise_schedule_args(parser: argparse.ArgumentParser):
+    group = parser.add_argument_group(title="Denoise schedule args")
+
+    group.add_argument(
+        "--denoise-type",
+        type=str,
+        default="flow",
+        help="Denoise type for noised inputs.",
+    )
+
+    # Flow Matching
+    group.add_argument(
+        "--flow-shift",
+        type=float,
+        default=7.0,
+        help="Shift factor for flow matching schedulers.",
+    )
+    group.add_argument(
+        "--flow-reverse",
+        action="store_true",
+        help="If reverse, learning/sampling from t=1 -> t=0.",
+    )
+    group.add_argument(
+        "--flow-solver",
+        type=str,
+        default="euler",
+        help="Solver for flow matching.",
+    )
+    group.add_argument(
+        "--use-linear-quadratic-schedule",
+        action="store_true",
+        help="Use linear quadratic schedule for flow matching."
+        "Following MovieGen (https://ai.meta.com/static-resource/movie-gen-research-paper)",
+    )
+    group.add_argument(
+        "--linear-schedule-end",
+        type=int,
+        default=25,
+        help="End step for linear quadratic schedule for flow matching.",
+    )
+
+    return parser
+
+
+def add_inference_args(parser: argparse.ArgumentParser):
+    group = parser.add_argument_group(title="Inference args")
+
+    # ======================== Model loads ========================
+    group.add_argument(
+        "--model-base",
+        type=str,
+        default=".",
+        help="Root path of all the models, including t2v models and extra models.",
+    )
+    group.add_argument(
+        "--dit-weight",
+        type=str,
+        default="./hunyuan-video-t2v-720p/transformers/mp_rank_00_model_states.pt",
+        help="Path to the HunyuanVideo model. If None, search the model in the args.model_root."
+        "1. If it is a file, load the model directly."
+        "2. If it is a directory, search the model in the directory. Support two types of models: "
+        "1) named `pytorch_model_*.pt`"
+        "2) named `*_model_states.pt`, where * can be `mp_rank_00`.",
+    )
+    group.add_argument(
+        "--model-resolution",
+        type=str,
+        default="540p",
+        choices=["540p", "720p"],
+        help="Root path of all the models, including t2v models and extra models.",
+    )
+    group.add_argument(
+        "--load-key",
+        type=str,
+        default="module",
+        help="Key to load the model states. 'module' for the main model, 'ema' for the EMA model.",
+    )
+    group.add_argument(
+        "--use-cpu-offload",
+        action="store_true",
+        help="Use CPU offload for the model load.",
+    )
+
+    # ======================== Inference general setting ========================
+    group.add_argument(
+        "--batch-size",
+        type=int,
+        default=1,
+        help="Batch size for inference and evaluation.",
+    )
+    group.add_argument(
+        "--infer-steps",
+        type=int,
+        default=50,
+        help="Number of denoising steps for inference.",
+    )
+    group.add_argument(
+        "--disable-autocast",
+        action="store_true",
+        help="Disable autocast for denoising loop and vae decoding in pipeline sampling.",
+    )
+    group.add_argument(
+        "--save-path",
+        type=str,
+        default="./results",
+        help="Path to save the generated samples.",
+    )
+    group.add_argument(
+        "--save-path-suffix",
+        type=str,
+        default="",
+        help="Suffix for the directory of saved samples.",
+    )
+    group.add_argument(
+        "--name-suffix",
+        type=str,
+        default="",
+        help="Suffix for the names of saved samples.",
+    )
+    group.add_argument(
+        "--num-videos",
+        type=int,
+        default=1,
+        help="Number of videos to generate for each prompt.",
+    )
+    # ---sample size---
+    group.add_argument(
+        "--video-size",
+        type=int,
+        nargs="+",
+        default=(720, 1280),
+        help="Video size for training. If a single value is provided, it will be used for both height "
+        "and width. If two values are provided, they will be used for height and width "
+        "respectively.",
+    )
+    group.add_argument(
+        "--video-length",
+        type=int,
+        default=129,
+        help="How many frames to sample from a video. if using 3d vae, the number should be 4n+1",
+    )
+    # --- prompt ---
+    group.add_argument(
+        "--prompt",
+        type=str,
+        default=None,
+        help="Prompt for sampling during evaluation.",
+    )
+    group.add_argument(
+        "--seed-type",
+        type=str,
+        default="auto",
+        choices=["file", "random", "fixed", "auto"],
+        help="Seed type for evaluation. If file, use the seed from the CSV file. If random, generate a "
+        "random seed. If fixed, use the fixed seed given by `--seed`. If auto, `csv` will use the "
+        "seed column if available, otherwise use the fixed `seed` value. `prompt` will use the "
+        "fixed `seed` value.",
+    )
+    group.add_argument("--seed", type=int, default=None, help="Seed for evaluation.")
+
+    # Classifier-Free Guidance
+    group.add_argument(
+        "--neg-prompt", type=str, default=None, help="Negative prompt for sampling."
+    )
+    group.add_argument(
+        "--cfg-scale", type=float, default=1.0, help="Classifier free guidance scale."
+    )
+    group.add_argument(
+        "--embedded-cfg-scale",
+        type=float,
+        default=6.0,
+        help="Embeded classifier free guidance scale.",
+    )
+
+    group.add_argument(
+        "--reproduce",
+        action="store_true",
+        help="Enable reproducibility by setting random seeds and deterministic algorithms.",
+    )
+
+    return parser
+
+
+def add_parallel_args(parser: argparse.ArgumentParser):
+    group = parser.add_argument_group(title="Parallel args")
+
+    # ======================== Model loads ========================
+    group.add_argument(
+        "--ulysses-degree",
+        type=int,
+        default=1,
+        help="Ulysses degree.",
+    )
+    group.add_argument(
+        "--ring-degree",
+        type=int,
+        default=1,
+        help="Ulysses degree.",
+    )
+
+    return parser
+
+
+def sanity_check_args(args):
+    # VAE channels
+    vae_pattern = r"\d{2,3}-\d{1,2}c-\w+"
+    if not re.match(vae_pattern, args.vae):
+        raise ValueError(
+            f"Invalid VAE model: {args.vae}. Must be in the format of '{vae_pattern}'."
+        )
+    vae_channels = int(args.vae.split("-")[1][:-1])
+    if args.latent_channels is None:
+        args.latent_channels = vae_channels
+    if vae_channels != args.latent_channels:
+        raise ValueError(
+            f"Latent channels ({args.latent_channels}) must match the VAE channels ({vae_channels})."
+        )
+    return args

hyvideo/constants.py

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+import os
+import torch
+
+__all__ = [
+    "C_SCALE",
+    "PROMPT_TEMPLATE",
+    "MODEL_BASE",
+    "PRECISIONS",
+    "NORMALIZATION_TYPE",
+    "ACTIVATION_TYPE",
+    "VAE_PATH",
+    "TEXT_ENCODER_PATH",
+    "TOKENIZER_PATH",
+    "TEXT_PROJECTION",
+    "DATA_TYPE",
+    "NEGATIVE_PROMPT",
+]
+
+PRECISION_TO_TYPE = {
+    'fp32': torch.float32,
+    'fp16': torch.float16,
+    'bf16': torch.bfloat16,
+}
+
+# =================== Constant Values =====================
+# Computation scale factor, 1P = 1_000_000_000_000_000. Tensorboard will display the value in PetaFLOPS to avoid
+# overflow error when tensorboard logging values.
+C_SCALE = 1_000_000_000_000_000
+
+# When using decoder-only models, we must provide a prompt template to instruct the text encoder
+# on how to generate the text.
+# --------------------------------------------------------------------
+PROMPT_TEMPLATE_ENCODE = (
+    "<|start_header_id|>system<|end_header_id|>\n\nDescribe the image by detailing the color, shape, size, texture, "
+    "quantity, text, spatial relationships of the objects and background:<|eot_id|>"
+    "<|start_header_id|>user<|end_header_id|>\n\n{}<|eot_id|>"
+) 
+PROMPT_TEMPLATE_ENCODE_VIDEO = (
+    "<|start_header_id|>system<|end_header_id|>\n\nDescribe the video by detailing the following aspects: "
+    "1. The main content and theme of the video."
+    "2. The color, shape, size, texture, quantity, text, and spatial relationships of the objects."
+    "3. Actions, events, behaviors temporal relationships, physical movement changes of the objects."
+    "4. background environment, light, style and atmosphere."
+    "5. camera angles, movements, and transitions used in the video:<|eot_id|>"
+    "<|start_header_id|>user<|end_header_id|>\n\n{}<|eot_id|>"
+)  
+
+NEGATIVE_PROMPT = "Aerial view, aerial view, overexposed, low quality, deformation, a poor composition, bad hands, bad teeth, bad eyes, bad limbs, distortion"
+
+PROMPT_TEMPLATE = {
+    "dit-llm-encode": {
+        "template": PROMPT_TEMPLATE_ENCODE,
+        "crop_start": 36,
+    },
+    "dit-llm-encode-video": {
+        "template": PROMPT_TEMPLATE_ENCODE_VIDEO,
+        "crop_start": 95,
+    },
+}
+
+# ======================= Model ======================
+PRECISIONS = {"fp32", "fp16", "bf16"}
+NORMALIZATION_TYPE = {"layer", "rms"}
+ACTIVATION_TYPE = {"relu", "silu", "gelu", "gelu_tanh"}
+
+# =================== Model Path =====================
+MODEL_BASE = os.getenv("MODEL_BASE", ".")
+
+# =================== Data =======================
+DATA_TYPE = {"image", "video", "image_video"}
+
+# 3D VAE
+VAE_PATH = {"884-16c-hy": f"{MODEL_BASE}/hunyuan-video-t2v-720p/vae"}
+
+# Text Encoder
+TEXT_ENCODER_PATH = {
+    "clipL": f"{MODEL_BASE}/text_encoder_2",
+    "llm": f"{MODEL_BASE}/text_encoder",
+}
+
+# Tokenizer
+TOKENIZER_PATH = {
+    "clipL": f"{MODEL_BASE}/text_encoder_2",
+    "llm": f"{MODEL_BASE}/text_encoder",
+}
+
+TEXT_PROJECTION = {
+    "linear",  # Default, an nn.Linear() layer
+    "single_refiner",  # Single TokenRefiner. Refer to LI-DiT
+}

hyvideo/diffusion/__init__.py

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+from .pipelines import HunyuanVideoPipeline
+from .schedulers import FlowMatchDiscreteScheduler

hyvideo/diffusion/pipelines/__init__.py

@@ -0,0 +1 @@
+from .pipeline_hunyuan_video import HunyuanVideoPipeline

hyvideo/diffusion/pipelines/pipeline_hunyuan_video.py

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+# Copyright 2024 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+#
+# Modified from diffusers==0.29.2
+#
+# ==============================================================================
+import inspect
+from typing import Any, Callable, Dict, List, Optional, Union, Tuple
+import torch
+import torch.distributed as dist
+import numpy as np
+from dataclasses import dataclass
+from packaging import version
+
+from diffusers.callbacks import MultiPipelineCallbacks, PipelineCallback
+from diffusers.configuration_utils import FrozenDict
+from diffusers.image_processor import VaeImageProcessor
+from diffusers.loaders import LoraLoaderMixin, TextualInversionLoaderMixin
+from diffusers.models import AutoencoderKL
+from diffusers.models.lora import adjust_lora_scale_text_encoder
+from diffusers.schedulers import KarrasDiffusionSchedulers
+from diffusers.utils import (
+    USE_PEFT_BACKEND,
+    deprecate,
+    logging,
+    replace_example_docstring,
+    scale_lora_layers,
+    unscale_lora_layers,
+)
+from diffusers.utils.torch_utils import randn_tensor
+from diffusers.pipelines.pipeline_utils import DiffusionPipeline
+from diffusers.utils import BaseOutput
+
+from ...constants import PRECISION_TO_TYPE
+from ...vae.autoencoder_kl_causal_3d import AutoencoderKLCausal3D
+from ...text_encoder import TextEncoder
+from ...modules import HYVideoDiffusionTransformer
+
+logger = logging.get_logger(__name__)  # pylint: disable=invalid-name
+
+EXAMPLE_DOC_STRING = """"""
+
+
+def rescale_noise_cfg(noise_cfg, noise_pred_text, guidance_rescale=0.0):
+    """
+    Rescale `noise_cfg` according to `guidance_rescale`. Based on findings of [Common Diffusion Noise Schedules and
+    Sample Steps are Flawed](https://arxiv.org/pdf/2305.08891.pdf). See Section 3.4
+    """
+    std_text = noise_pred_text.std(
+        dim=list(range(1, noise_pred_text.ndim)), keepdim=True
+    )
+    std_cfg = noise_cfg.std(dim=list(range(1, noise_cfg.ndim)), keepdim=True)
+    # rescale the results from guidance (fixes overexposure)
+    noise_pred_rescaled = noise_cfg * (std_text / std_cfg)
+    # mix with the original results from guidance by factor guidance_rescale to avoid "plain looking" images
+    noise_cfg = (
+        guidance_rescale * noise_pred_rescaled + (1 - guidance_rescale) * noise_cfg
+    )
+    return noise_cfg
+
+
+def retrieve_timesteps(
+    scheduler,
+    num_inference_steps: Optional[int] = None,
+    device: Optional[Union[str, torch.device]] = None,
+    timesteps: Optional[List[int]] = None,
+    sigmas: Optional[List[float]] = None,
+    **kwargs,
+):
+    """
+    Calls the scheduler's `set_timesteps` method and retrieves timesteps from the scheduler after the call. Handles
+    custom timesteps. Any kwargs will be supplied to `scheduler.set_timesteps`.
+
+    Args:
+        scheduler (`SchedulerMixin`):
+            The scheduler to get timesteps from.
+        num_inference_steps (`int`):
+            The number of diffusion steps used when generating samples with a pre-trained model. If used, `timesteps`
+            must be `None`.
+        device (`str` or `torch.device`, *optional*):
+            The device to which the timesteps should be moved to. If `None`, the timesteps are not moved.
+        timesteps (`List[int]`, *optional*):
+            Custom timesteps used to override the timestep spacing strategy of the scheduler. If `timesteps` is passed,
+            `num_inference_steps` and `sigmas` must be `None`.
+        sigmas (`List[float]`, *optional*):
+            Custom sigmas used to override the timestep spacing strategy of the scheduler. If `sigmas` is passed,
+            `num_inference_steps` and `timesteps` must be `None`.
+
+    Returns:
+        `Tuple[torch.Tensor, int]`: A tuple where the first element is the timestep schedule from the scheduler and the
+        second element is the number of inference steps.
+    """
+    if timesteps is not None and sigmas is not None:
+        raise ValueError(
+            "Only one of `timesteps` or `sigmas` can be passed. Please choose one to set custom values"
+        )
+    if timesteps is not None:
+        accepts_timesteps = "timesteps" in set(
+            inspect.signature(scheduler.set_timesteps).parameters.keys()
+        )
+        if not accepts_timesteps:
+            raise ValueError(
+                f"The current scheduler class {scheduler.__class__}'s `set_timesteps` does not support custom"
+                f" timestep schedules. Please check whether you are using the correct scheduler."
+            )
+        scheduler.set_timesteps(timesteps=timesteps, device=device, **kwargs)
+        timesteps = scheduler.timesteps
+        num_inference_steps = len(timesteps)
+    elif sigmas is not None:
+        accept_sigmas = "sigmas" in set(
+            inspect.signature(scheduler.set_timesteps).parameters.keys()
+        )
+        if not accept_sigmas:
+            raise ValueError(
+                f"The current scheduler class {scheduler.__class__}'s `set_timesteps` does not support custom"
+                f" sigmas schedules. Please check whether you are using the correct scheduler."
+            )
+        scheduler.set_timesteps(sigmas=sigmas, device=device, **kwargs)
+        timesteps = scheduler.timesteps
+        num_inference_steps = len(timesteps)
+    else:
+        scheduler.set_timesteps(num_inference_steps, device=device, **kwargs)
+        timesteps = scheduler.timesteps
+    return timesteps, num_inference_steps
+
+
+@dataclass
+class HunyuanVideoPipelineOutput(BaseOutput):
+    videos: Union[torch.Tensor, np.ndarray]
+
+
+class HunyuanVideoPipeline(DiffusionPipeline):
+    r"""
+    Pipeline for text-to-video generation using HunyuanVideo.
+
+    This model inherits from [`DiffusionPipeline`]. Check the superclass documentation for the generic methods
+    implemented for all pipelines (downloading, saving, running on a particular device, etc.).
+
+    Args:
+        vae ([`AutoencoderKL`]):
+            Variational Auto-Encoder (VAE) model to encode and decode images to and from latent representations.
+        text_encoder ([`TextEncoder`]):
+            Frozen text-encoder.
+        text_encoder_2 ([`TextEncoder`]):
+            Frozen text-encoder_2.
+        transformer ([`HYVideoDiffusionTransformer`]):
+            A `HYVideoDiffusionTransformer` to denoise the encoded video latents.
+        scheduler ([`SchedulerMixin`]):
+            A scheduler to be used in combination with `unet` to denoise the encoded image latents.
+    """
+
+    model_cpu_offload_seq = "text_encoder->text_encoder_2->transformer->vae"
+    _optional_components = ["text_encoder_2"]
+    _exclude_from_cpu_offload = ["transformer"]
+    _callback_tensor_inputs = ["latents", "prompt_embeds", "negative_prompt_embeds"]
+
+    def __init__(
+        self,
+        vae: AutoencoderKL,
+        text_encoder: TextEncoder,
+        transformer: HYVideoDiffusionTransformer,
+        scheduler: KarrasDiffusionSchedulers,
+        text_encoder_2: Optional[TextEncoder] = None,
+        progress_bar_config: Dict[str, Any] = None,
+        args=None,
+    ):
+        super().__init__()
+
+        # ==========================================================================================
+        if progress_bar_config is None:
+            progress_bar_config = {}
+        if not hasattr(self, "_progress_bar_config"):
+            self._progress_bar_config = {}
+        self._progress_bar_config.update(progress_bar_config)
+
+        self.args = args
+        # ==========================================================================================
+
+        if (
+            hasattr(scheduler.config, "steps_offset")
+            and scheduler.config.steps_offset != 1
+        ):
+            deprecation_message = (
+                f"The configuration file of this scheduler: {scheduler} is outdated. `steps_offset`"
+                f" should be set to 1 instead of {scheduler.config.steps_offset}. Please make sure "
+                "to update the config accordingly as leaving `steps_offset` might led to incorrect results"
+                " in future versions. If you have downloaded this checkpoint from the Hugging Face Hub,"
+                " it would be very nice if you could open a Pull request for the `scheduler/scheduler_config.json`"
+                " file"
+            )
+            deprecate(
+                "steps_offset!=1", "1.0.0", deprecation_message, standard_warn=False
+            )
+            new_config = dict(scheduler.config)
+            new_config["steps_offset"] = 1
+            scheduler._internal_dict = FrozenDict(new_config)
+
+        if (
+            hasattr(scheduler.config, "clip_sample")
+            and scheduler.config.clip_sample is True
+        ):
+            deprecation_message = (
+                f"The configuration file of this scheduler: {scheduler} has not set the configuration `clip_sample`."
+                " `clip_sample` should be set to False in the configuration file. Please make sure to update the"
+                " config accordingly as not setting `clip_sample` in the config might lead to incorrect results in"
+                " future versions. If you have downloaded this checkpoint from the Hugging Face Hub, it would be very"
+                " nice if you could open a Pull request for the `scheduler/scheduler_config.json` file"
+            )
+            deprecate(
+                "clip_sample not set", "1.0.0", deprecation_message, standard_warn=False
+            )
+            new_config = dict(scheduler.config)
+            new_config["clip_sample"] = False
+            scheduler._internal_dict = FrozenDict(new_config)
+
+        self.register_modules(
+            vae=vae,
+            text_encoder=text_encoder,
+            transformer=transformer,
+            scheduler=scheduler,
+            text_encoder_2=text_encoder_2,
+        )
+        self.vae_scale_factor = 2 ** (len(self.vae.config.block_out_channels) - 1)
+        self.image_processor = VaeImageProcessor(vae_scale_factor=self.vae_scale_factor)
+
+    def encode_prompt(
+        self,
+        prompt,
+        device,
+        num_videos_per_prompt,
+        do_classifier_free_guidance,
+        negative_prompt=None,
+        prompt_embeds: Optional[torch.Tensor] = None,
+        attention_mask: Optional[torch.Tensor] = None,
+        negative_prompt_embeds: Optional[torch.Tensor] = None,
+        negative_attention_mask: Optional[torch.Tensor] = None,
+        lora_scale: Optional[float] = None,
+        clip_skip: Optional[int] = None,
+        text_encoder: Optional[TextEncoder] = None,
+        data_type: Optional[str] = "image",
+    ):
+        r"""
+        Encodes the prompt into text encoder hidden states.
+
+        Args:
+            prompt (`str` or `List[str]`, *optional*):
+                prompt to be encoded
+            device: (`torch.device`):
+                torch device
+            num_videos_per_prompt (`int`):
+                number of videos that should be generated per prompt
+            do_classifier_free_guidance (`bool`):
+                whether to use classifier free guidance or not
+            negative_prompt (`str` or `List[str]`, *optional*):
+                The prompt or prompts not to guide the video generation. If not defined, one has to pass
+                `negative_prompt_embeds` instead. Ignored when not using guidance (i.e., ignored if `guidance_scale` is
+                less than `1`).
+            prompt_embeds (`torch.Tensor`, *optional*):
+                Pre-generated text embeddings. Can be used to easily tweak text inputs, *e.g.* prompt weighting. If not
+                provided, text embeddings will be generated from `prompt` input argument.
+            attention_mask (`torch.Tensor`, *optional*):
+            negative_prompt_embeds (`torch.Tensor`, *optional*):
+                Pre-generated negative text embeddings. Can be used to easily tweak text inputs, *e.g.* prompt
+                weighting. If not provided, negative_prompt_embeds will be generated from `negative_prompt` input
+                argument.
+            negative_attention_mask (`torch.Tensor`, *optional*):
+            lora_scale (`float`, *optional*):
+                A LoRA scale that will be applied to all LoRA layers of the text encoder if LoRA layers are loaded.
+            clip_skip (`int`, *optional*):
+                Number of layers to be skipped from CLIP while computing the prompt embeddings. A value of 1 means that
+                the output of the pre-final layer will be used for computing the prompt embeddings.
+            text_encoder (TextEncoder, *optional*):
+            data_type (`str`, *optional*):
+        """
+        if text_encoder is None:
+            text_encoder = self.text_encoder
+
+        # set lora scale so that monkey patched LoRA
+        # function of text encoder can correctly access it
+        if lora_scale is not None and isinstance(self, LoraLoaderMixin):
+            self._lora_scale = lora_scale
+
+            # dynamically adjust the LoRA scale
+            if not USE_PEFT_BACKEND:
+                adjust_lora_scale_text_encoder(text_encoder.model, lora_scale)
+            else:
+                scale_lora_layers(text_encoder.model, lora_scale)
+
+        if prompt is not None and isinstance(prompt, str):
+            batch_size = 1
+        elif prompt is not None and isinstance(prompt, list):
+            batch_size = len(prompt)
+        else:
+            batch_size = prompt_embeds.shape[0]
+
+        if prompt_embeds is None:
+            # textual inversion: process multi-vector tokens if necessary
+            if isinstance(self, TextualInversionLoaderMixin):
+                prompt = self.maybe_convert_prompt(prompt, text_encoder.tokenizer)
+
+            text_inputs = text_encoder.text2tokens(prompt, data_type=data_type)
+
+            if clip_skip is None:
+                prompt_outputs = text_encoder.encode(
+                    text_inputs, data_type=data_type, device=device
+                )
+                prompt_embeds = prompt_outputs.hidden_state
+            else:
+                prompt_outputs = text_encoder.encode(
+                    text_inputs,
+                    output_hidden_states=True,
+                    data_type=data_type,
+                    device=device,
+                )
+                # Access the `hidden_states` first, that contains a tuple of
+                # all the hidden states from the encoder layers. Then index into
+                # the tuple to access the hidden states from the desired layer.
+                prompt_embeds = prompt_outputs.hidden_states_list[-(clip_skip + 1)]
+                # We also need to apply the final LayerNorm here to not mess with the
+                # representations. The `last_hidden_states` that we typically use for
+                # obtaining the final prompt representations passes through the LayerNorm
+                # layer.
+                prompt_embeds = text_encoder.model.text_model.final_layer_norm(
+                    prompt_embeds
+                )
+
+            attention_mask = prompt_outputs.attention_mask
+            if attention_mask is not None:
+                attention_mask = attention_mask.to(device)
+                bs_embed, seq_len = attention_mask.shape
+                attention_mask = attention_mask.repeat(1, num_videos_per_prompt)
+                attention_mask = attention_mask.view(
+                    bs_embed * num_videos_per_prompt, seq_len
+                )
+
+        if text_encoder is not None:
+            prompt_embeds_dtype = text_encoder.dtype
+        elif self.transformer is not None:
+            prompt_embeds_dtype = self.transformer.dtype
+        else:
+            prompt_embeds_dtype = prompt_embeds.dtype
+
+        prompt_embeds = prompt_embeds.to(dtype=prompt_embeds_dtype, device=device)
+
+        if prompt_embeds.ndim == 2:
+            bs_embed, _ = prompt_embeds.shape
+            # duplicate text embeddings for each generation per prompt, using mps friendly method
+            prompt_embeds = prompt_embeds.repeat(1, num_videos_per_prompt)
+            prompt_embeds = prompt_embeds.view(bs_embed * num_videos_per_prompt, -1)
+        else:
+            bs_embed, seq_len, _ = prompt_embeds.shape
+            # duplicate text embeddings for each generation per prompt, using mps friendly method
+            prompt_embeds = prompt_embeds.repeat(1, num_videos_per_prompt, 1)
+            prompt_embeds = prompt_embeds.view(
+                bs_embed * num_videos_per_prompt, seq_len, -1
+            )
+
+        # get unconditional embeddings for classifier free guidance
+        if do_classifier_free_guidance and negative_prompt_embeds is None:
+            uncond_tokens: List[str]
+            if negative_prompt is None:
+                uncond_tokens = [""] * batch_size
+            elif prompt is not None and type(prompt) is not type(negative_prompt):
+                raise TypeError(
+                    f"`negative_prompt` should be the same type to `prompt`, but got {type(negative_prompt)} !="
+                    f" {type(prompt)}."
+                )
+            elif isinstance(negative_prompt, str):
+                uncond_tokens = [negative_prompt]
+            elif batch_size != len(negative_prompt):
+                raise ValueError(
+                    f"`negative_prompt`: {negative_prompt} has batch size {len(negative_prompt)}, but `prompt`:"
+                    f" {prompt} has batch size {batch_size}. Please make sure that passed `negative_prompt` matches"
+                    " the batch size of `prompt`."
+                )
+            else:
+                uncond_tokens = negative_prompt
+
+            # textual inversion: process multi-vector tokens if necessary
+            if isinstance(self, TextualInversionLoaderMixin):
+                uncond_tokens = self.maybe_convert_prompt(
+                    uncond_tokens, text_encoder.tokenizer
+                )
+
+            # max_length = prompt_embeds.shape[1]
+            uncond_input = text_encoder.text2tokens(uncond_tokens, data_type=data_type)
+
+            negative_prompt_outputs = text_encoder.encode(
+                uncond_input, data_type=data_type, device=device
+            )
+            negative_prompt_embeds = negative_prompt_outputs.hidden_state
+
+            negative_attention_mask = negative_prompt_outputs.attention_mask
+            if negative_attention_mask is not None:
+                negative_attention_mask = negative_attention_mask.to(device)
+                _, seq_len = negative_attention_mask.shape
+                negative_attention_mask = negative_attention_mask.repeat(
+                    1, num_videos_per_prompt
+                )
+                negative_attention_mask = negative_attention_mask.view(
+                    batch_size * num_videos_per_prompt, seq_len
+                )
+
+        if do_classifier_free_guidance:
+            # duplicate unconditional embeddings for each generation per prompt, using mps friendly method
+            seq_len = negative_prompt_embeds.shape[1]
+
+            negative_prompt_embeds = negative_prompt_embeds.to(
+                dtype=prompt_embeds_dtype, device=device
+            )
+
+            if negative_prompt_embeds.ndim == 2:
+                negative_prompt_embeds = negative_prompt_embeds.repeat(
+                    1, num_videos_per_prompt
+                )
+                negative_prompt_embeds = negative_prompt_embeds.view(
+                    batch_size * num_videos_per_prompt, -1
+                )
+            else:
+                negative_prompt_embeds = negative_prompt_embeds.repeat(
+                    1, num_videos_per_prompt, 1
+                )
+                negative_prompt_embeds = negative_prompt_embeds.view(
+                    batch_size * num_videos_per_prompt, seq_len, -1
+                )
+
+        if text_encoder is not None:
+            if isinstance(self, LoraLoaderMixin) and USE_PEFT_BACKEND:
+                # Retrieve the original scale by scaling back the LoRA layers
+                unscale_lora_layers(text_encoder.model, lora_scale)
+
+        return (
+            prompt_embeds,
+            negative_prompt_embeds,
+            attention_mask,
+            negative_attention_mask,
+        )
+
+    def decode_latents(self, latents, enable_tiling=True):
+        deprecation_message = "The decode_latents method is deprecated and will be removed in 1.0.0. Please use VaeImageProcessor.postprocess(...) instead"
+        deprecate("decode_latents", "1.0.0", deprecation_message, standard_warn=False)
+
+        latents = 1 / self.vae.config.scaling_factor * latents
+        if enable_tiling:
+            self.vae.enable_tiling()
+            image = self.vae.decode(latents, return_dict=False)[0]
+        else:
+            image = self.vae.decode(latents, return_dict=False)[0]
+        image = (image / 2 + 0.5).clamp(0, 1)
+        # we always cast to float32 as this does not cause significant overhead and is compatible with bfloat16
+        if image.ndim == 4:
+            image = image.cpu().permute(0, 2, 3, 1).float()
+        else:
+            image = image.cpu().float()
+        return image
+
+    def prepare_extra_func_kwargs(self, func, kwargs):
+        # prepare extra kwargs for the scheduler step, since not all schedulers have the same signature
+        # eta (η) is only used with the DDIMScheduler, it will be ignored for other schedulers.
+        # eta corresponds to η in DDIM paper: https://arxiv.org/abs/2010.02502
+        # and should be between [0, 1]
+        extra_step_kwargs = {}
+
+        for k, v in kwargs.items():
+            accepts = k in set(inspect.signature(func).parameters.keys())
+            if accepts:
+                extra_step_kwargs[k] = v
+        return extra_step_kwargs
+
+    def check_inputs(
+        self,
+        prompt,
+        height,
+        width,
+        video_length,
+        callback_steps,
+        negative_prompt=None,
+        prompt_embeds=None,
+        negative_prompt_embeds=None,
+        callback_on_step_end_tensor_inputs=None,
+        vae_ver="88-4c-sd",
+    ):
+        if height % 8 != 0 or width % 8 != 0:
+            raise ValueError(
+                f"`height` and `width` have to be divisible by 8 but are {height} and {width}."
+            )
+
+        if video_length is not None:
+            if "884" in vae_ver:
+                if video_length != 1 and (video_length - 1) % 4 != 0:
+                    raise ValueError(
+                        f"`video_length` has to be 1 or a multiple of 4 but is {video_length}."
+                    )
+            elif "888" in vae_ver:
+                if video_length != 1 and (video_length - 1) % 8 != 0:
+                    raise ValueError(
+                        f"`video_length` has to be 1 or a multiple of 8 but is {video_length}."
+                    )
+
+        if callback_steps is not None and (
+            not isinstance(callback_steps, int) or callback_steps <= 0
+        ):
+            raise ValueError(
+                f"`callback_steps` has to be a positive integer but is {callback_steps} of type"
+                f" {type(callback_steps)}."
+            )
+        if callback_on_step_end_tensor_inputs is not None and not all(
+            k in self._callback_tensor_inputs
+            for k in callback_on_step_end_tensor_inputs
+        ):
+            raise ValueError(
+                f"`callback_on_step_end_tensor_inputs` has to be in {self._callback_tensor_inputs}, but found {[k for k in callback_on_step_end_tensor_inputs if k not in self._callback_tensor_inputs]}"
+            )
+
+        if prompt is not None and prompt_embeds is not None:
+            raise ValueError(
+                f"Cannot forward both `prompt`: {prompt} and `prompt_embeds`: {prompt_embeds}. Please make sure to"
+                " only forward one of the two."
+            )
+        elif prompt is None and prompt_embeds is None:
+            raise ValueError(
+                "Provide either `prompt` or `prompt_embeds`. Cannot leave both `prompt` and `prompt_embeds` undefined."
+            )
+        elif prompt is not None and (
+            not isinstance(prompt, str) and not isinstance(prompt, list)
+        ):
+            raise ValueError(
+                f"`prompt` has to be of type `str` or `list` but is {type(prompt)}"
+            )
+
+        if negative_prompt is not None and negative_prompt_embeds is not None:
+            raise ValueError(
+                f"Cannot forward both `negative_prompt`: {negative_prompt} and `negative_prompt_embeds`:"
+                f" {negative_prompt_embeds}. Please make sure to only forward one of the two."
+            )
+
+        if prompt_embeds is not None and negative_prompt_embeds is not None:
+            if prompt_embeds.shape != negative_prompt_embeds.shape:
+                raise ValueError(
+                    "`prompt_embeds` and `negative_prompt_embeds` must have the same shape when passed directly, but"
+                    f" got: `prompt_embeds` {prompt_embeds.shape} != `negative_prompt_embeds`"
+                    f" {negative_prompt_embeds.shape}."
+                )
+
+
+    def prepare_latents(
+        self,
+        batch_size,
+        num_channels_latents,
+        height,
+        width,
+        video_length,
+        dtype,
+        device,
+        generator,
+        latents=None,
+    ):
+        shape = (
+            batch_size,
+            num_channels_latents,
+            video_length,
+            int(height) // self.vae_scale_factor,
+            int(width) // self.vae_scale_factor,
+        )
+        if isinstance(generator, list) and len(generator) != batch_size:
+            raise ValueError(
+                f"You have passed a list of generators of length {len(generator)}, but requested an effective batch"
+                f" size of {batch_size}. Make sure the batch size matches the length of the generators."
+            )
+
+        if latents is None:
+            latents = randn_tensor(
+                shape, generator=generator, device=device, dtype=dtype
+            )
+        else:
+            latents = latents.to(device)
+
+        # Check existence to make it compatible with FlowMatchEulerDiscreteScheduler
+        if hasattr(self.scheduler, "init_noise_sigma"):
+            # scale the initial noise by the standard deviation required by the scheduler
+            latents = latents * self.scheduler.init_noise_sigma
+        return latents
+
+    # Copied from diffusers.pipelines.latent_consistency_models.pipeline_latent_consistency_text2img.LatentConsistencyModelPipeline.get_guidance_scale_embedding
+    def get_guidance_scale_embedding(
+        self,
+        w: torch.Tensor,
+        embedding_dim: int = 512,
+        dtype: torch.dtype = torch.float32,
+    ) -> torch.Tensor:
+        """
+        See https://github.com/google-research/vdm/blob/dc27b98a554f65cdc654b800da5aa1846545d41b/model_vdm.py#L298
+
+        Args:
+            w (`torch.Tensor`):
+                Generate embedding vectors with a specified guidance scale to subsequently enrich timestep embeddings.
+            embedding_dim (`int`, *optional*, defaults to 512):
+                Dimension of the embeddings to generate.
+            dtype (`torch.dtype`, *optional*, defaults to `torch.float32`):
+                Data type of the generated embeddings.
+
+        Returns:
+            `torch.Tensor`: Embedding vectors with shape `(len(w), embedding_dim)`.
+        """
+        assert len(w.shape) == 1
+        w = w * 1000.0
+
+        half_dim = embedding_dim // 2
+        emb = torch.log(torch.tensor(10000.0)) / (half_dim - 1)
+        emb = torch.exp(torch.arange(half_dim, dtype=dtype) * -emb)
+        emb = w.to(dtype)[:, None] * emb[None, :]
+        emb = torch.cat([torch.sin(emb), torch.cos(emb)], dim=1)
+        if embedding_dim % 2 == 1:  # zero pad
+            emb = torch.nn.functional.pad(emb, (0, 1))
+        assert emb.shape == (w.shape[0], embedding_dim)
+        return emb
+
+    @property
+    def guidance_scale(self):
+        return self._guidance_scale
+
+    @property
+    def guidance_rescale(self):
+        return self._guidance_rescale
+
+    @property
+    def clip_skip(self):
+        return self._clip_skip
+
+    # here `guidance_scale` is defined analog to the guidance weight `w` of equation (2)
+    # of the Imagen paper: https://arxiv.org/pdf/2205.11487.pdf . `guidance_scale = 1`
+    # corresponds to doing no classifier free guidance.
+    @property
+    def do_classifier_free_guidance(self):
+        # return self._guidance_scale > 1 and self.transformer.config.time_cond_proj_dim is None
+        return self._guidance_scale > 1
+
+    @property
+    def cross_attention_kwargs(self):
+        return self._cross_attention_kwargs
+
+    @property
+    def num_timesteps(self):
+        return self._num_timesteps
+
+    @property
+    def interrupt(self):
+        return self._interrupt
+
+    @torch.no_grad()
+    @replace_example_docstring(EXAMPLE_DOC_STRING)
+    def __call__(
+        self,
+        prompt: Union[str, List[str]],
+        height: int,
+        width: int,
+        video_length: int,
+        data_type: str = "video",
+        num_inference_steps: int = 50,
+        timesteps: List[int] = None,
+        sigmas: List[float] = None,
+        guidance_scale: float = 7.5,
+        negative_prompt: Optional[Union[str, List[str]]] = None,
+        num_videos_per_prompt: Optional[int] = 1,
+        eta: float = 0.0,
+        generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None,
+        latents: Optional[torch.Tensor] = None,
+        prompt_embeds: Optional[torch.Tensor] = None,
+        attention_mask: Optional[torch.Tensor] = None,
+        negative_prompt_embeds: Optional[torch.Tensor] = None,
+        negative_attention_mask: Optional[torch.Tensor] = None,
+        output_type: Optional[str] = "pil",
+        return_dict: bool = True,
+        cross_attention_kwargs: Optional[Dict[str, Any]] = None,
+        guidance_rescale: float = 0.0,
+        clip_skip: Optional[int] = None,
+        callback_on_step_end: Optional[
+            Union[
+                Callable[[int, int, Dict], None],
+                PipelineCallback,
+                MultiPipelineCallbacks,
+            ]
+        ] = None,
+        callback_on_step_end_tensor_inputs: List[str] = ["latents"],
+        freqs_cis: Tuple[torch.Tensor, torch.Tensor] = None,
+        vae_ver: str = "88-4c-sd",
+        enable_tiling: bool = False,
+        n_tokens: Optional[int] = None,
+        embedded_guidance_scale: Optional[float] = None,
+        **kwargs,
+    ):
+        r"""
+        The call function to the pipeline for generation.
+
+        Args:
+            prompt (`str` or `List[str]`):
+                The prompt or prompts to guide image generation. If not defined, you need to pass `prompt_embeds`.
+            height (`int`):
+                The height in pixels of the generated image.
+            width (`int`):
+                The width in pixels of the generated image.
+            video_length (`int`):
+                The number of frames in the generated video.
+            num_inference_steps (`int`, *optional*, defaults to 50):
+                The number of denoising steps. More denoising steps usually lead to a higher quality image at the
+                expense of slower inference.
+            timesteps (`List[int]`, *optional*):
+                Custom timesteps to use for the denoising process with schedulers which support a `timesteps` argument
+                in their `set_timesteps` method. If not defined, the default behavior when `num_inference_steps` is
+                passed will be used. Must be in descending order.
+            sigmas (`List[float]`, *optional*):
+                Custom sigmas to use for the denoising process with schedulers which support a `sigmas` argument in
+                their `set_timesteps` method. If not defined, the default behavior when `num_inference_steps` is passed
+                will be used.
+            guidance_scale (`float`, *optional*, defaults to 7.5):
+                A higher guidance scale value encourages the model to generate images closely linked to the text
+                `prompt` at the expense of lower image quality. Guidance scale is enabled when `guidance_scale > 1`.
+            negative_prompt (`str` or `List[str]`, *optional*):
+                The prompt or prompts to guide what to not include in image generation. If not defined, you need to
+                pass `negative_prompt_embeds` instead. Ignored when not using guidance (`guidance_scale < 1`).
+            num_videos_per_prompt (`int`, *optional*, defaults to 1):
+                The number of images to generate per prompt.
+            eta (`float`, *optional*, defaults to 0.0):
+                Corresponds to parameter eta (η) from the [DDIM](https://arxiv.org/abs/2010.02502) paper. Only applies
+                to the [`~schedulers.DDIMScheduler`], and is ignored in other schedulers.
+            generator (`torch.Generator` or `List[torch.Generator]`, *optional*):
+                A [`torch.Generator`](https://pytorch.org/docs/stable/generated/torch.Generator.html) to make
+                generation deterministic.
+            latents (`torch.Tensor`, *optional*):
+                Pre-generated noisy latents sampled from a Gaussian distribution, to be used as inputs for image
+                generation. Can be used to tweak the same generation with different prompts. If not provided, a latents
+                tensor is generated by sampling using the supplied random `generator`.
+            prompt_embeds (`torch.Tensor`, *optional*):
+                Pre-generated text embeddings. Can be used to easily tweak text inputs (prompt weighting). If not
+                provided, text embeddings are generated from the `prompt` input argument.
+            negative_prompt_embeds (`torch.Tensor`, *optional*):
+                Pre-generated negative text embeddings. Can be used to easily tweak text inputs (prompt weighting). If
+                not provided, `negative_prompt_embeds` are generated from the `negative_prompt` input argument.
+                
+            output_type (`str`, *optional*, defaults to `"pil"`):
+                The output format of the generated image. Choose between `PIL.Image` or `np.array`.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`HunyuanVideoPipelineOutput`] instead of a
+                plain tuple.
+            cross_attention_kwargs (`dict`, *optional*):
+                A kwargs dictionary that if specified is passed along to the [`AttentionProcessor`] as defined in
+                [`self.processor`](https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention_processor.py).
+            guidance_rescale (`float`, *optional*, defaults to 0.0):
+                Guidance rescale factor from [Common Diffusion Noise Schedules and Sample Steps are
+                Flawed](https://arxiv.org/pdf/2305.08891.pdf). Guidance rescale factor should fix overexposure when
+                using zero terminal SNR.
+            clip_skip (`int`, *optional*):
+                Number of layers to be skipped from CLIP while computing the prompt embeddings. A value of 1 means that
+                the output of the pre-final layer will be used for computing the prompt embeddings.
+            callback_on_step_end (`Callable`, `PipelineCallback`, `MultiPipelineCallbacks`, *optional*):
+                A function or a subclass of `PipelineCallback` or `MultiPipelineCallbacks` that is called at the end of
+                each denoising step during the inference. with the following arguments: `callback_on_step_end(self:
+                DiffusionPipeline, step: int, timestep: int, callback_kwargs: Dict)`. `callback_kwargs` will include a
+                list of all tensors as specified by `callback_on_step_end_tensor_inputs`.
+            callback_on_step_end_tensor_inputs (`List`, *optional*):
+                The list of tensor inputs for the `callback_on_step_end` function. The tensors specified in the list
+                will be passed as `callback_kwargs` argument. You will only be able to include variables listed in the
+                `._callback_tensor_inputs` attribute of your pipeline class.
+
+        Examples:
+
+        Returns:
+            [`~HunyuanVideoPipelineOutput`] or `tuple`:
+                If `return_dict` is `True`, [`HunyuanVideoPipelineOutput`] is returned,
+                otherwise a `tuple` is returned where the first element is a list with the generated images and the
+                second element is a list of `bool`s indicating whether the corresponding generated image contains
+                "not-safe-for-work" (nsfw) content.
+        """
+        callback = kwargs.pop("callback", None)
+        callback_steps = kwargs.pop("callback_steps", None)
+
+        if callback is not None:
+            deprecate(
+                "callback",
+                "1.0.0",
+                "Passing `callback` as an input argument to `__call__` is deprecated, consider using `callback_on_step_end`",
+            )
+        if callback_steps is not None:
+            deprecate(
+                "callback_steps",
+                "1.0.0",
+                "Passing `callback_steps` as an input argument to `__call__` is deprecated, consider using `callback_on_step_end`",
+            )
+
+        if isinstance(callback_on_step_end, (PipelineCallback, MultiPipelineCallbacks)):
+            callback_on_step_end_tensor_inputs = callback_on_step_end.tensor_inputs
+
+        # 0. Default height and width to unet
+        # height = height or self.transformer.config.sample_size * self.vae_scale_factor
+        # width = width or self.transformer.config.sample_size * self.vae_scale_factor
+        # to deal with lora scaling and other possible forward hooks
+
+        # 1. Check inputs. Raise error if not correct
+        self.check_inputs(
+            prompt,
+            height,
+            width,
+            video_length,
+            callback_steps,
+            negative_prompt,
+            prompt_embeds,
+            negative_prompt_embeds,
+            callback_on_step_end_tensor_inputs,
+            vae_ver=vae_ver,
+        )
+
+        self._guidance_scale = guidance_scale
+        self._guidance_rescale = guidance_rescale
+        self._clip_skip = clip_skip
+        self._cross_attention_kwargs = cross_attention_kwargs
+        self._interrupt = False
+
+        # 2. Define call parameters
+        if prompt is not None and isinstance(prompt, str):
+            batch_size = 1
+        elif prompt is not None and isinstance(prompt, list):
+            batch_size = len(prompt)
+        else:
+            batch_size = prompt_embeds.shape[0]
+
+        device = torch.device(f"cuda:{dist.get_rank()}") if dist.is_initialized() else self._execution_device
+
+        # 3. Encode input prompt
+        lora_scale = (
+            self.cross_attention_kwargs.get("scale", None)
+            if self.cross_attention_kwargs is not None
+            else None
+        )
+
+        (
+            prompt_embeds,
+            negative_prompt_embeds,
+            prompt_mask,
+            negative_prompt_mask,
+        ) = self.encode_prompt(
+            prompt,
+            device,
+            num_videos_per_prompt,
+            self.do_classifier_free_guidance,
+            negative_prompt,
+            prompt_embeds=prompt_embeds,
+            attention_mask=attention_mask,
+            negative_prompt_embeds=negative_prompt_embeds,
+            negative_attention_mask=negative_attention_mask,
+            lora_scale=lora_scale,
+            clip_skip=self.clip_skip,
+            data_type=data_type,
+        )
+        if self.text_encoder_2 is not None:
+            (
+                prompt_embeds_2,
+                negative_prompt_embeds_2,
+                prompt_mask_2,
+                negative_prompt_mask_2,
+            ) = self.encode_prompt(
+                prompt,
+                device,
+                num_videos_per_prompt,
+                self.do_classifier_free_guidance,
+                negative_prompt,
+                prompt_embeds=None,
+                attention_mask=None,
+                negative_prompt_embeds=None,
+                negative_attention_mask=None,
+                lora_scale=lora_scale,
+                clip_skip=self.clip_skip,
+                text_encoder=self.text_encoder_2,
+                data_type=data_type,
+            )
+        else:
+            prompt_embeds_2 = None
+            negative_prompt_embeds_2 = None
+            prompt_mask_2 = None
+            negative_prompt_mask_2 = None
+
+        # For classifier free guidance, we need to do two forward passes.
+        # Here we concatenate the unconditional and text embeddings into a single batch
+        # to avoid doing two forward passes
+        if self.do_classifier_free_guidance:
+            prompt_embeds = torch.cat([negative_prompt_embeds, prompt_embeds])
+            if prompt_mask is not None:
+                prompt_mask = torch.cat([negative_prompt_mask, prompt_mask])
+            if prompt_embeds_2 is not None:
+                prompt_embeds_2 = torch.cat([negative_prompt_embeds_2, prompt_embeds_2])
+            if prompt_mask_2 is not None:
+                prompt_mask_2 = torch.cat([negative_prompt_mask_2, prompt_mask_2])
+
+
+        # 4. Prepare timesteps
+        extra_set_timesteps_kwargs = self.prepare_extra_func_kwargs(
+            self.scheduler.set_timesteps, {"n_tokens": n_tokens}
+        )
+        timesteps, num_inference_steps = retrieve_timesteps(
+            self.scheduler,
+            num_inference_steps,
+            device,
+            timesteps,
+            sigmas,
+            **extra_set_timesteps_kwargs,
+        )
+
+        if "884" in vae_ver:
+            video_length = (video_length - 1) // 4 + 1
+        elif "888" in vae_ver:
+            video_length = (video_length - 1) // 8 + 1
+        else:
+            video_length = video_length
+
+        # 5. Prepare latent variables
+        num_channels_latents = self.transformer.config.in_channels
+        latents = self.prepare_latents(
+            batch_size * num_videos_per_prompt,
+            num_channels_latents,
+            height,
+            width,
+            video_length,
+            prompt_embeds.dtype,
+            device,
+            generator,
+            latents,
+        )
+
+        # 6. Prepare extra step kwargs. TODO: Logic should ideally just be moved out of the pipeline
+        extra_step_kwargs = self.prepare_extra_func_kwargs(
+            self.scheduler.step,
+            {"generator": generator, "eta": eta},
+        )
+
+        target_dtype = PRECISION_TO_TYPE[self.args.precision]
+        autocast_enabled = (
+            target_dtype != torch.float32
+        ) and not self.args.disable_autocast
+        vae_dtype = PRECISION_TO_TYPE[self.args.vae_precision]
+        vae_autocast_enabled = (
+            vae_dtype != torch.float32
+        ) and not self.args.disable_autocast
+
+        # 7. Denoising loop
+        num_warmup_steps = len(timesteps) - num_inference_steps * self.scheduler.order
+        self._num_timesteps = len(timesteps)
+
+        # if is_progress_bar:
+        with self.progress_bar(total=num_inference_steps) as progress_bar:
+            for i, t in enumerate(timesteps):
+                if self.interrupt:
+                    continue
+
+                # expand the latents if we are doing classifier free guidance
+                latent_model_input = (
+                    torch.cat([latents] * 2)
+                    if self.do_classifier_free_guidance
+                    else latents
+                )
+                latent_model_input = self.scheduler.scale_model_input(
+                    latent_model_input, t
+                )
+
+                t_expand = t.repeat(latent_model_input.shape[0])
+                guidance_expand = (
+                    torch.tensor(
+                        [embedded_guidance_scale] * latent_model_input.shape[0],
+                        dtype=torch.float32,
+                        device=device,
+                    ).to(target_dtype)
+                    * 1000.0
+                    if embedded_guidance_scale is not None
+                    else None
+                )
+
+                # predict the noise residual
+                with torch.autocast(
+                    device_type="cuda", dtype=target_dtype, enabled=autocast_enabled
+                ):
+                    noise_pred = self.transformer(  # For an input image (129, 192, 336) (1, 256, 256)
+                        latent_model_input,  # [2, 16, 33, 24, 42]
+                        t_expand,  # [2]
+                        text_states=prompt_embeds,  # [2, 256, 4096]
+                        text_mask=prompt_mask,  # [2, 256]
+                        text_states_2=prompt_embeds_2,  # [2, 768]
+                        freqs_cos=freqs_cis[0],  # [seqlen, head_dim]
+                        freqs_sin=freqs_cis[1],  # [seqlen, head_dim]
+                        guidance=guidance_expand,
+                        return_dict=True,
+                    )[
+                        "x"
+                    ]
+
+                # perform guidance
+                if self.do_classifier_free_guidance:
+                    noise_pred_uncond, noise_pred_text = noise_pred.chunk(2)
+                    noise_pred = noise_pred_uncond + self.guidance_scale * (
+                        noise_pred_text - noise_pred_uncond
+                    )
+
+                if self.do_classifier_free_guidance and self.guidance_rescale > 0.0:
+                    # Based on 3.4. in https://arxiv.org/pdf/2305.08891.pdf
+                    noise_pred = rescale_noise_cfg(
+                        noise_pred,
+                        noise_pred_text,
+                        guidance_rescale=self.guidance_rescale,
+                    )
+
+                # compute the previous noisy sample x_t -> x_t-1
+                latents = self.scheduler.step(
+                    noise_pred, t, latents, **extra_step_kwargs, return_dict=False
+                )[0]
+
+                if callback_on_step_end is not None:
+                    callback_kwargs = {}
+                    for k in callback_on_step_end_tensor_inputs:
+                        callback_kwargs[k] = locals()[k]
+                    callback_outputs = callback_on_step_end(self, i, t, callback_kwargs)
+
+                    latents = callback_outputs.pop("latents", latents)
+                    prompt_embeds = callback_outputs.pop("prompt_embeds", prompt_embeds)
+                    negative_prompt_embeds = callback_outputs.pop(
+                        "negative_prompt_embeds", negative_prompt_embeds
+                    )
+
+                # call the callback, if provided
+                if i == len(timesteps) - 1 or (
+                    (i + 1) > num_warmup_steps and (i + 1) % self.scheduler.order == 0
+                ):
+                    if progress_bar is not None:
+                        progress_bar.update()
+                    if callback is not None and i % callback_steps == 0:
+                        step_idx = i // getattr(self.scheduler, "order", 1)
+                        callback(step_idx, t, latents)
+
+        if not output_type == "latent":
+            expand_temporal_dim = False
+            if len(latents.shape) == 4:
+                if isinstance(self.vae, AutoencoderKLCausal3D):
+                    latents = latents.unsqueeze(2)
+                    expand_temporal_dim = True
+            elif len(latents.shape) == 5:
+                pass
+            else:
+                raise ValueError(
+                    f"Only support latents with shape (b, c, h, w) or (b, c, f, h, w), but got {latents.shape}."
+                )
+
+            if (
+                hasattr(self.vae.config, "shift_factor")
+                and self.vae.config.shift_factor
+            ):
+                latents = (
+                    latents / self.vae.config.scaling_factor
+                    + self.vae.config.shift_factor
+                )
+            else:
+                latents = latents / self.vae.config.scaling_factor
+
+            with torch.autocast(
+                device_type="cuda", dtype=vae_dtype, enabled=vae_autocast_enabled
+            ):
+                if enable_tiling:
+                    self.vae.enable_tiling()
+                    image = self.vae.decode(
+                        latents, return_dict=False, generator=generator
+                    )[0]
+                else:
+                    image = self.vae.decode(
+                        latents, return_dict=False, generator=generator
+                    )[0]
+
+            if expand_temporal_dim or image.shape[2] == 1:
+                image = image.squeeze(2)
+
+        else:
+            image = latents
+
+        image = (image / 2 + 0.5).clamp(0, 1)
+        # we always cast to float32 as this does not cause significant overhead and is compatible with bfloa16
+        image = image.cpu().float()
+
+        # Offload all models
+        self.maybe_free_model_hooks()
+
+        if not return_dict:
+            return image
+
+        return HunyuanVideoPipelineOutput(videos=image)

hyvideo/diffusion/schedulers/__init__.py

@@ -0,0 +1 @@
+from .scheduling_flow_match_discrete import FlowMatchDiscreteScheduler

hyvideo/diffusion/schedulers/scheduling_flow_match_discrete.py

@@ -0,0 +1,257 @@
+# Copyright 2024 Stability AI, Katherine Crowson and The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+#
+# Modified from diffusers==0.29.2
+#
+# ==============================================================================
+
+from dataclasses import dataclass
+from typing import Optional, Tuple, Union
+
+import numpy as np
+import torch
+
+from diffusers.configuration_utils import ConfigMixin, register_to_config
+from diffusers.utils import BaseOutput, logging
+from diffusers.schedulers.scheduling_utils import SchedulerMixin
+
+
+logger = logging.get_logger(__name__)  # pylint: disable=invalid-name
+
+
+@dataclass
+class FlowMatchDiscreteSchedulerOutput(BaseOutput):
+    """
+    Output class for the scheduler's `step` function output.
+
+    Args:
+        prev_sample (`torch.FloatTensor` of shape `(batch_size, num_channels, height, width)` for images):
+            Computed sample `(x_{t-1})` of previous timestep. `prev_sample` should be used as next model input in the
+            denoising loop.
+    """
+
+    prev_sample: torch.FloatTensor
+
+
+class FlowMatchDiscreteScheduler(SchedulerMixin, ConfigMixin):
+    """
+    Euler scheduler.
+
+    This model inherits from [`SchedulerMixin`] and [`ConfigMixin`]. Check the superclass documentation for the generic
+    methods the library implements for all schedulers such as loading and saving.
+
+    Args:
+        num_train_timesteps (`int`, defaults to 1000):
+            The number of diffusion steps to train the model.
+        timestep_spacing (`str`, defaults to `"linspace"`):
+            The way the timesteps should be scaled. Refer to Table 2 of the [Common Diffusion Noise Schedules and
+            Sample Steps are Flawed](https://huggingface.co/papers/2305.08891) for more information.
+        shift (`float`, defaults to 1.0):
+            The shift value for the timestep schedule.
+        reverse (`bool`, defaults to `True`):
+            Whether to reverse the timestep schedule.
+    """
+
+    _compatibles = []
+    order = 1
+
+    @register_to_config
+    def __init__(
+        self,
+        num_train_timesteps: int = 1000,
+        shift: float = 1.0,
+        reverse: bool = True,
+        solver: str = "euler",
+        n_tokens: Optional[int] = None,
+    ):
+        sigmas = torch.linspace(1, 0, num_train_timesteps + 1)
+
+        if not reverse:
+            sigmas = sigmas.flip(0)
+
+        self.sigmas = sigmas
+        # the value fed to model
+        self.timesteps = (sigmas[:-1] * num_train_timesteps).to(dtype=torch.float32)
+
+        self._step_index = None
+        self._begin_index = None
+
+        self.supported_solver = ["euler"]
+        if solver not in self.supported_solver:
+            raise ValueError(
+                f"Solver {solver} not supported. Supported solvers: {self.supported_solver}"
+            )
+
+    @property
+    def step_index(self):
+        """
+        The index counter for current timestep. It will increase 1 after each scheduler step.
+        """
+        return self._step_index
+
+    @property
+    def begin_index(self):
+        """
+        The index for the first timestep. It should be set from pipeline with `set_begin_index` method.
+        """
+        return self._begin_index
+
+    # Copied from diffusers.schedulers.scheduling_dpmsolver_multistep.DPMSolverMultistepScheduler.set_begin_index
+    def set_begin_index(self, begin_index: int = 0):
+        """
+        Sets the begin index for the scheduler. This function should be run from pipeline before the inference.
+
+        Args:
+            begin_index (`int`):
+                The begin index for the scheduler.
+        """
+        self._begin_index = begin_index
+
+    def _sigma_to_t(self, sigma):
+        return sigma * self.config.num_train_timesteps
+
+    def set_timesteps(
+        self,
+        num_inference_steps: int,
+        device: Union[str, torch.device] = None,
+        n_tokens: int = None,
+    ):
+        """
+        Sets the discrete timesteps used for the diffusion chain (to be run before inference).
+
+        Args:
+            num_inference_steps (`int`):
+                The number of diffusion steps used when generating samples with a pre-trained model.
+            device (`str` or `torch.device`, *optional*):
+                The device to which the timesteps should be moved to. If `None`, the timesteps are not moved.
+            n_tokens (`int`, *optional*):
+                Number of tokens in the input sequence.
+        """
+        self.num_inference_steps = num_inference_steps
+        
+        sigmas = torch.linspace(1, 0, num_inference_steps + 1)
+        sigmas = self.sd3_time_shift(sigmas)
+
+        if not self.config.reverse:
+            sigmas = 1 - sigmas
+
+        self.sigmas = sigmas
+        self.timesteps = (sigmas[:-1] * self.config.num_train_timesteps).to(
+            dtype=torch.float32, device=device
+        )
+
+        # Reset step index
+        self._step_index = None
+
+    def index_for_timestep(self, timestep, schedule_timesteps=None):
+        if schedule_timesteps is None:
+            schedule_timesteps = self.timesteps
+
+        indices = (schedule_timesteps == timestep).nonzero()
+
+        # The sigma index that is taken for the **very** first `step`
+        # is always the second index (or the last index if there is only 1)
+        # This way we can ensure we don't accidentally skip a sigma in
+        # case we start in the middle of the denoising schedule (e.g. for image-to-image)
+        pos = 1 if len(indices) > 1 else 0
+
+        return indices[pos].item()
+
+    def _init_step_index(self, timestep):
+        if self.begin_index is None:
+            if isinstance(timestep, torch.Tensor):
+                timestep = timestep.to(self.timesteps.device)
+            self._step_index = self.index_for_timestep(timestep)
+        else:
+            self._step_index = self._begin_index
+
+    def scale_model_input(
+        self, sample: torch.Tensor, timestep: Optional[int] = None
+    ) -> torch.Tensor:
+        return sample
+
+    def sd3_time_shift(self, t: torch.Tensor):
+        return (self.config.shift * t) / (1 + (self.config.shift - 1) * t)
+
+    def step(
+        self,
+        model_output: torch.FloatTensor,
+        timestep: Union[float, torch.FloatTensor],
+        sample: torch.FloatTensor,
+        return_dict: bool = True,
+    ) -> Union[FlowMatchDiscreteSchedulerOutput, Tuple]:
+        """
+        Predict the sample from the previous timestep by reversing the SDE. This function propagates the diffusion
+        process from the learned model outputs (most often the predicted noise).
+
+        Args:
+            model_output (`torch.FloatTensor`):
+                The direct output from learned diffusion model.
+            timestep (`float`):
+                The current discrete timestep in the diffusion chain.
+            sample (`torch.FloatTensor`):
+                A current instance of a sample created by the diffusion process.
+            generator (`torch.Generator`, *optional*):
+                A random number generator.
+            n_tokens (`int`, *optional*):
+                Number of tokens in the input sequence.
+            return_dict (`bool`):
+                Whether or not to return a [`~schedulers.scheduling_euler_discrete.EulerDiscreteSchedulerOutput`] or
+                tuple.
+
+        Returns:
+            [`~schedulers.scheduling_euler_discrete.EulerDiscreteSchedulerOutput`] or `tuple`:
+                If return_dict is `True`, [`~schedulers.scheduling_euler_discrete.EulerDiscreteSchedulerOutput`] is
+                returned, otherwise a tuple is returned where the first element is the sample tensor.
+        """
+
+        if (
+            isinstance(timestep, int)
+            or isinstance(timestep, torch.IntTensor)
+            or isinstance(timestep, torch.LongTensor)
+        ):
+            raise ValueError(
+                (
+                    "Passing integer indices (e.g. from `enumerate(timesteps)`) as timesteps to"
+                    " `EulerDiscreteScheduler.step()` is not supported. Make sure to pass"
+                    " one of the `scheduler.timesteps` as a timestep."
+                ),
+            )
+
+        if self.step_index is None:
+            self._init_step_index(timestep)
+
+        # Upcast to avoid precision issues when computing prev_sample
+        sample = sample.to(torch.float32)
+
+        dt = self.sigmas[self.step_index + 1] - self.sigmas[self.step_index]
+
+        if self.config.solver == "euler":
+            prev_sample = sample + model_output.to(torch.float32) * dt
+        else:
+            raise ValueError(
+                f"Solver {self.config.solver} not supported. Supported solvers: {self.supported_solver}"
+            )
+
+        # upon completion increase step index by one
+        self._step_index += 1
+
+        if not return_dict:
+            return (prev_sample,)
+
+        return FlowMatchDiscreteSchedulerOutput(prev_sample=prev_sample)
+
+    def __len__(self):
+        return self.config.num_train_timesteps

hyvideo/inference.py

@@ -0,0 +1,672 @@
+import os
+import time
+import random
+import functools
+from typing import List, Optional, Tuple, Union
+
+from pathlib import Path
+from loguru import logger
+
+import torch
+import torch.distributed as dist
+from hyvideo.constants import PROMPT_TEMPLATE, NEGATIVE_PROMPT, PRECISION_TO_TYPE
+from hyvideo.vae import load_vae
+from hyvideo.modules import load_model
+from hyvideo.text_encoder import TextEncoder
+from hyvideo.utils.data_utils import align_to
+from hyvideo.modules.posemb_layers import get_nd_rotary_pos_embed
+from hyvideo.diffusion.schedulers import FlowMatchDiscreteScheduler
+from hyvideo.diffusion.pipelines import HunyuanVideoPipeline
+
+try:
+    import xfuser
+    from xfuser.core.distributed import (
+        get_sequence_parallel_world_size,
+        get_sequence_parallel_rank,
+        get_sp_group,
+        initialize_model_parallel,
+        init_distributed_environment
+    )
+except:
+    xfuser = None
+    get_sequence_parallel_world_size = None
+    get_sequence_parallel_rank = None
+    get_sp_group = None
+    initialize_model_parallel = None
+    init_distributed_environment = None
+
+
+def parallelize_transformer(pipe):
+    transformer = pipe.transformer
+    original_forward = transformer.forward
+
+    @functools.wraps(transformer.__class__.forward)
+    def new_forward(
+        self,
+        x: torch.Tensor,
+        t: torch.Tensor,  # Should be in range(0, 1000).
+        text_states: torch.Tensor = None,
+        text_mask: torch.Tensor = None,  # Now we don't use it.
+        text_states_2: Optional[torch.Tensor] = None,  # Text embedding for modulation.
+        freqs_cos: Optional[torch.Tensor] = None,
+        freqs_sin: Optional[torch.Tensor] = None,
+        guidance: torch.Tensor = None,  # Guidance for modulation, should be cfg_scale x 1000.
+        return_dict: bool = True,
+    ):
+        if x.shape[-2] // 2 % get_sequence_parallel_world_size() == 0:
+            # try to split x by height
+            split_dim = -2
+        elif x.shape[-1] // 2 % get_sequence_parallel_world_size() == 0:
+            # try to split x by width
+            split_dim = -1
+        else:
+            raise ValueError(f"Cannot split video sequence into ulysses_degree x ring_degree ({get_sequence_parallel_world_size()}) parts evenly")
+
+        # patch sizes for the temporal, height, and width dimensions are 1, 2, and 2.
+        temporal_size, h, w = x.shape[2], x.shape[3] // 2, x.shape[4] // 2
+
+        x = torch.chunk(x, get_sequence_parallel_world_size(),dim=split_dim)[get_sequence_parallel_rank()]
+
+        dim_thw = freqs_cos.shape[-1]
+        freqs_cos = freqs_cos.reshape(temporal_size, h, w, dim_thw)
+        freqs_cos = torch.chunk(freqs_cos, get_sequence_parallel_world_size(),dim=split_dim - 1)[get_sequence_parallel_rank()]
+        freqs_cos = freqs_cos.reshape(-1, dim_thw)
+        dim_thw = freqs_sin.shape[-1]
+        freqs_sin = freqs_sin.reshape(temporal_size, h, w, dim_thw)
+        freqs_sin = torch.chunk(freqs_sin, get_sequence_parallel_world_size(),dim=split_dim - 1)[get_sequence_parallel_rank()]
+        freqs_sin = freqs_sin.reshape(-1, dim_thw)
+        
+        from xfuser.core.long_ctx_attention import xFuserLongContextAttention
+        
+        for block in transformer.double_blocks + transformer.single_blocks:
+            block.hybrid_seq_parallel_attn = xFuserLongContextAttention()
+
+        output = original_forward(
+            x,
+            t,
+            text_states,
+            text_mask,
+            text_states_2,
+            freqs_cos,
+            freqs_sin,
+            guidance,
+            return_dict,
+        )
+
+        return_dict = not isinstance(output, tuple)
+        sample = output["x"]
+        sample = get_sp_group().all_gather(sample, dim=split_dim)
+        output["x"] = sample
+        return output
+
+    new_forward = new_forward.__get__(transformer)
+    transformer.forward = new_forward
+    
+
+class Inference(object):
+    def __init__(
+        self,
+        args,
+        vae,
+        vae_kwargs,
+        text_encoder,
+        model,
+        text_encoder_2=None,
+        pipeline=None,
+        use_cpu_offload=False,
+        device=None,
+        logger=None,
+        parallel_args=None,
+    ):
+        self.vae = vae
+        self.vae_kwargs = vae_kwargs
+
+        self.text_encoder = text_encoder
+        self.text_encoder_2 = text_encoder_2
+
+        self.model = model
+        self.pipeline = pipeline
+        self.use_cpu_offload = use_cpu_offload
+
+        self.args = args
+        self.device = (
+            device
+            if device is not None
+            else "cuda"
+            if torch.cuda.is_available()
+            else "cpu"
+        )
+        self.logger = logger
+        self.parallel_args = parallel_args
+
+    @classmethod
+    def from_pretrained(cls, pretrained_model_path, args, device=None, **kwargs):
+        """
+        Initialize the Inference pipeline.
+
+        Args:
+            pretrained_model_path (str or pathlib.Path): The model path, including t2v, text encoder and vae checkpoints.
+            args (argparse.Namespace): The arguments for the pipeline.
+            device (int): The device for inference. Default is 0.
+        """
+        # ========================================================================
+        logger.info(f"Got text-to-video model root path: {pretrained_model_path}")
+        
+        # ==================== Initialize Distributed Environment ================
+        if args.ulysses_degree > 1 or args.ring_degree > 1:
+            assert xfuser is not None, \
+                "Ulysses Attention and Ring Attention requires xfuser package."
+
+            assert args.use_cpu_offload is False, \
+                "Cannot enable use_cpu_offload in the distributed environment."
+
+            dist.init_process_group("nccl")
+
+            assert dist.get_world_size() == args.ring_degree * args.ulysses_degree, \
+                "number of GPUs should be equal to ring_degree * ulysses_degree."
+
+            init_distributed_environment(rank=dist.get_rank(), world_size=dist.get_world_size())
+            
+            initialize_model_parallel(
+                sequence_parallel_degree=dist.get_world_size(),
+                ring_degree=args.ring_degree,
+                ulysses_degree=args.ulysses_degree,
+            )
+            device = torch.device(f"cuda:{os.environ['LOCAL_RANK']}")
+        else:
+            if device is None:
+                device = "cuda" if torch.cuda.is_available() else "cpu"
+
+        parallel_args = {"ulysses_degree": args.ulysses_degree, "ring_degree": args.ring_degree}
+
+        # ======================== Get the args path =============================
+
+        # Disable gradient
+        torch.set_grad_enabled(False)
+
+        # =========================== Build main model ===========================
+        logger.info("Building model...")
+        factor_kwargs = {"device": device, "dtype": PRECISION_TO_TYPE[args.precision]}
+        in_channels = args.latent_channels
+        out_channels = args.latent_channels
+
+        model = load_model(
+            args,
+            in_channels=in_channels,
+            out_channels=out_channels,
+            factor_kwargs=factor_kwargs,
+        )
+        model = model.to(device)
+        model = Inference.load_state_dict(args, model, pretrained_model_path)
+        model.eval()
+
+        # ============================= Build extra models ========================
+        # VAE
+        vae, _, s_ratio, t_ratio = load_vae(
+            args.vae,
+            args.vae_precision,
+            logger=logger,
+            device=device if not args.use_cpu_offload else "cpu",
+        )
+        vae_kwargs = {"s_ratio": s_ratio, "t_ratio": t_ratio}
+
+        # Text encoder
+        if args.prompt_template_video is not None:
+            crop_start = PROMPT_TEMPLATE[args.prompt_template_video].get(
+                "crop_start", 0
+            )
+        elif args.prompt_template is not None:
+            crop_start = PROMPT_TEMPLATE[args.prompt_template].get("crop_start", 0)
+        else:
+            crop_start = 0
+        max_length = args.text_len + crop_start
+
+        # prompt_template
+        prompt_template = (
+            PROMPT_TEMPLATE[args.prompt_template]
+            if args.prompt_template is not None
+            else None
+        )
+
+        # prompt_template_video
+        prompt_template_video = (
+            PROMPT_TEMPLATE[args.prompt_template_video]
+            if args.prompt_template_video is not None
+            else None
+        )
+
+        text_encoder = TextEncoder(
+            text_encoder_type=args.text_encoder,
+            max_length=max_length,
+            text_encoder_precision=args.text_encoder_precision,
+            tokenizer_type=args.tokenizer,
+            prompt_template=prompt_template,
+            prompt_template_video=prompt_template_video,
+            hidden_state_skip_layer=args.hidden_state_skip_layer,
+            apply_final_norm=args.apply_final_norm,
+            reproduce=args.reproduce,
+            logger=logger,
+            device=device if not args.use_cpu_offload else "cpu",
+        )
+        text_encoder_2 = None
+        if args.text_encoder_2 is not None:
+            text_encoder_2 = TextEncoder(
+                text_encoder_type=args.text_encoder_2,
+                max_length=args.text_len_2,
+                text_encoder_precision=args.text_encoder_precision_2,
+                tokenizer_type=args.tokenizer_2,
+                reproduce=args.reproduce,
+                logger=logger,
+                device=device if not args.use_cpu_offload else "cpu",
+            )
+
+        return cls(
+            args=args,
+            vae=vae,
+            vae_kwargs=vae_kwargs,
+            text_encoder=text_encoder,
+            text_encoder_2=text_encoder_2,
+            model=model,
+            use_cpu_offload=args.use_cpu_offload,
+            device=device,
+            logger=logger,
+            parallel_args=parallel_args
+        )
+
+    @staticmethod
+    def load_state_dict(args, model, pretrained_model_path):
+        load_key = args.load_key
+        dit_weight = Path(args.dit_weight)
+
+        if dit_weight is None:
+            model_dir = pretrained_model_path / f"t2v_{args.model_resolution}"
+            files = list(model_dir.glob("*.pt"))
+            if len(files) == 0:
+                raise ValueError(f"No model weights found in {model_dir}")
+            if str(files[0]).startswith("pytorch_model_"):
+                model_path = dit_weight / f"pytorch_model_{load_key}.pt"
+                bare_model = True
+            elif any(str(f).endswith("_model_states.pt") for f in files):
+                files = [f for f in files if str(f).endswith("_model_states.pt")]
+                model_path = files[0]
+                if len(files) > 1:
+                    logger.warning(
+                        f"Multiple model weights found in {dit_weight}, using {model_path}"
+                    )
+                bare_model = False
+            else:
+                raise ValueError(
+                    f"Invalid model path: {dit_weight} with unrecognized weight format: "
+                    f"{list(map(str, files))}. When given a directory as --dit-weight, only "
+                    f"`pytorch_model_*.pt`(provided by HunyuanDiT official) and "
+                    f"`*_model_states.pt`(saved by deepspeed) can be parsed. If you want to load a "
+                    f"specific weight file, please provide the full path to the file."
+                )
+        else:
+            if dit_weight.is_dir():
+                files = list(dit_weight.glob("*.pt"))
+                if len(files) == 0:
+                    raise ValueError(f"No model weights found in {dit_weight}")
+                if str(files[0]).startswith("pytorch_model_"):
+                    model_path = dit_weight / f"pytorch_model_{load_key}.pt"
+                    bare_model = True
+                elif any(str(f).endswith("_model_states.pt") for f in files):
+                    files = [f for f in files if str(f).endswith("_model_states.pt")]
+                    model_path = files[0]
+                    if len(files) > 1:
+                        logger.warning(
+                            f"Multiple model weights found in {dit_weight}, using {model_path}"
+                        )
+                    bare_model = False
+                else:
+                    raise ValueError(
+                        f"Invalid model path: {dit_weight} with unrecognized weight format: "
+                        f"{list(map(str, files))}. When given a directory as --dit-weight, only "
+                        f"`pytorch_model_*.pt`(provided by HunyuanDiT official) and "
+                        f"`*_model_states.pt`(saved by deepspeed) can be parsed. If you want to load a "
+                        f"specific weight file, please provide the full path to the file."
+                    )
+            elif dit_weight.is_file():
+                model_path = dit_weight
+                bare_model = "unknown"
+            else:
+                raise ValueError(f"Invalid model path: {dit_weight}")
+
+        if not model_path.exists():
+            raise ValueError(f"model_path not exists: {model_path}")
+        logger.info(f"Loading torch model {model_path}...")
+        state_dict = torch.load(model_path, map_location=lambda storage, loc: storage)
+
+        if bare_model == "unknown" and ("ema" in state_dict or "module" in state_dict):
+            bare_model = False
+        if bare_model is False:
+            if load_key in state_dict:
+                state_dict = state_dict[load_key]
+            else:
+                raise KeyError(
+                    f"Missing key: `{load_key}` in the checkpoint: {model_path}. The keys in the checkpoint "
+                    f"are: {list(state_dict.keys())}."
+                )
+        model.load_state_dict(state_dict, strict=True)
+        return model
+
+    @staticmethod
+    def parse_size(size):
+        if isinstance(size, int):
+            size = [size]
+        if not isinstance(size, (list, tuple)):
+            raise ValueError(f"Size must be an integer or (height, width), got {size}.")
+        if len(size) == 1:
+            size = [size[0], size[0]]
+        if len(size) != 2:
+            raise ValueError(f"Size must be an integer or (height, width), got {size}.")
+        return size
+
+
+class HunyuanVideoSampler(Inference):
+    def __init__(
+        self,
+        args,
+        vae,
+        vae_kwargs,
+        text_encoder,
+        model,
+        text_encoder_2=None,
+        pipeline=None,
+        use_cpu_offload=False,
+        device=0,
+        logger=None,
+        parallel_args=None
+    ):
+        super().__init__(
+            args,
+            vae,
+            vae_kwargs,
+            text_encoder,
+            model,
+            text_encoder_2=text_encoder_2,
+            pipeline=pipeline,
+            use_cpu_offload=use_cpu_offload,
+            device=device,
+            logger=logger,
+            parallel_args=parallel_args
+        )
+
+        self.pipeline = self.load_diffusion_pipeline(
+            args=args,
+            vae=self.vae,
+            text_encoder=self.text_encoder,
+            text_encoder_2=self.text_encoder_2,
+            model=self.model,
+            device=self.device,
+        )
+
+        self.default_negative_prompt = NEGATIVE_PROMPT
+
+    def load_diffusion_pipeline(
+        self,
+        args,
+        vae,
+        text_encoder,
+        text_encoder_2,
+        model,
+        scheduler=None,
+        device=None,
+        progress_bar_config=None,
+        data_type="video",
+    ):
+        """Load the denoising scheduler for inference."""
+        if scheduler is None:
+            if args.denoise_type == "flow":
+                scheduler = FlowMatchDiscreteScheduler(
+                    shift=args.flow_shift,
+                    reverse=args.flow_reverse,
+                    solver=args.flow_solver,
+                )
+            else:
+                raise ValueError(f"Invalid denoise type {args.denoise_type}")
+
+        pipeline = HunyuanVideoPipeline(
+            vae=vae,
+            text_encoder=text_encoder,
+            text_encoder_2=text_encoder_2,
+            transformer=model,
+            scheduler=scheduler,
+            progress_bar_config=progress_bar_config,
+            args=args,
+        )
+        if self.use_cpu_offload:
+            pipeline.enable_sequential_cpu_offload()
+        else:
+            pipeline = pipeline.to(device)
+
+        return pipeline
+
+    def get_rotary_pos_embed(self, video_length, height, width):
+        target_ndim = 3
+        ndim = 5 - 2
+        # 884
+        if "884" in self.args.vae:
+            latents_size = [(video_length - 1) // 4 + 1, height // 8, width // 8]
+        elif "888" in self.args.vae:
+            latents_size = [(video_length - 1) // 8 + 1, height // 8, width // 8]
+        else:
+            latents_size = [video_length, height // 8, width // 8]
+
+        if isinstance(self.model.patch_size, int):
+            assert all(s % self.model.patch_size == 0 for s in latents_size), (
+                f"Latent size(last {ndim} dimensions) should be divisible by patch size({self.model.patch_size}), "
+                f"but got {latents_size}."
+            )
+            rope_sizes = [s // self.model.patch_size for s in latents_size]
+        elif isinstance(self.model.patch_size, list):
+            assert all(
+                s % self.model.patch_size[idx] == 0
+                for idx, s in enumerate(latents_size)
+            ), (
+                f"Latent size(last {ndim} dimensions) should be divisible by patch size({self.model.patch_size}), "
+                f"but got {latents_size}."
+            )
+            rope_sizes = [
+                s // self.model.patch_size[idx] for idx, s in enumerate(latents_size)
+            ]
+
+        if len(rope_sizes) != target_ndim:
+            rope_sizes = [1] * (target_ndim - len(rope_sizes)) + rope_sizes  # time axis
+        head_dim = self.model.hidden_size // self.model.heads_num
+        rope_dim_list = self.model.rope_dim_list
+        if rope_dim_list is None:
+            rope_dim_list = [head_dim // target_ndim for _ in range(target_ndim)]
+        assert (
+            sum(rope_dim_list) == head_dim
+        ), "sum(rope_dim_list) should equal to head_dim of attention layer"
+        freqs_cos, freqs_sin = get_nd_rotary_pos_embed(
+            rope_dim_list,
+            rope_sizes,
+            theta=self.args.rope_theta,
+            use_real=True,
+            theta_rescale_factor=1,
+        )
+        return freqs_cos, freqs_sin
+
+    @torch.no_grad()
+    def predict(
+        self,
+        prompt,
+        height=192,
+        width=336,
+        video_length=129,
+        seed=None,
+        negative_prompt=None,
+        infer_steps=50,
+        guidance_scale=6,
+        flow_shift=5.0,
+        embedded_guidance_scale=None,
+        batch_size=1,
+        num_videos_per_prompt=1,
+        **kwargs,
+    ):
+        """
+        Predict the image/video from the given text.
+
+        Args:
+            prompt (str or List[str]): The input text.
+            kwargs:
+                height (int): The height of the output video. Default is 192.
+                width (int): The width of the output video. Default is 336.
+                video_length (int): The frame number of the output video. Default is 129.
+                seed (int or List[str]): The random seed for the generation. Default is a random integer.
+                negative_prompt (str or List[str]): The negative text prompt. Default is an empty string.
+                guidance_scale (float): The guidance scale for the generation. Default is 6.0.
+                num_images_per_prompt (int): The number of images per prompt. Default is 1.
+                infer_steps (int): The number of inference steps. Default is 100.
+        """
+        if self.parallel_args['ulysses_degree'] > 1 or self.parallel_args['ring_degree'] > 1:
+            assert seed is not None, \
+                "You have to set a seed in the distributed environment, please rerun with --seed <your-seed>."
+
+            parallelize_transformer(self.pipeline)
+
+        out_dict = dict()
+
+        # ========================================================================
+        # Arguments: seed
+        # ========================================================================
+        if isinstance(seed, torch.Tensor):
+            seed = seed.tolist()
+        if seed is None:
+            seeds = [
+                random.randint(0, 1_000_000)
+                for _ in range(batch_size * num_videos_per_prompt)
+            ]
+        elif isinstance(seed, int):
+            seeds = [
+                seed + i
+                for _ in range(batch_size)
+                for i in range(num_videos_per_prompt)
+            ]
+        elif isinstance(seed, (list, tuple)):
+            if len(seed) == batch_size:
+                seeds = [
+                    int(seed[i]) + j
+                    for i in range(batch_size)
+                    for j in range(num_videos_per_prompt)
+                ]
+            elif len(seed) == batch_size * num_videos_per_prompt:
+                seeds = [int(s) for s in seed]
+            else:
+                raise ValueError(
+                    f"Length of seed must be equal to number of prompt(batch_size) or "
+                    f"batch_size * num_videos_per_prompt ({batch_size} * {num_videos_per_prompt}), got {seed}."
+                )
+        else:
+            raise ValueError(
+                f"Seed must be an integer, a list of integers, or None, got {seed}."
+            )
+        generator = [torch.Generator(self.device).manual_seed(seed) for seed in seeds]
+        out_dict["seeds"] = seeds
+
+        # ========================================================================
+        # Arguments: target_width, target_height, target_video_length
+        # ========================================================================
+        if width <= 0 or height <= 0 or video_length <= 0:
+            raise ValueError(
+                f"`height` and `width` and `video_length` must be positive integers, got height={height}, width={width}, video_length={video_length}"
+            )
+        if (video_length - 1) % 4 != 0:
+            raise ValueError(
+                f"`video_length-1` must be a multiple of 4, got {video_length}"
+            )
+
+        logger.info(
+            f"Input (height, width, video_length) = ({height}, {width}, {video_length})"
+        )
+
+        target_height = align_to(height, 16)
+        target_width = align_to(width, 16)
+        target_video_length = video_length
+
+        out_dict["size"] = (target_height, target_width, target_video_length)
+
+        # ========================================================================
+        # Arguments: prompt, new_prompt, negative_prompt
+        # ========================================================================
+        if not isinstance(prompt, str):
+            raise TypeError(f"`prompt` must be a string, but got {type(prompt)}")
+        prompt = [prompt.strip()]
+
+        # negative prompt
+        if negative_prompt is None or negative_prompt == "":
+            negative_prompt = self.default_negative_prompt
+        if not isinstance(negative_prompt, str):
+            raise TypeError(
+                f"`negative_prompt` must be a string, but got {type(negative_prompt)}"
+            )
+        negative_prompt = [negative_prompt.strip()]
+
+        # ========================================================================
+        # Scheduler
+        # ========================================================================
+        scheduler = FlowMatchDiscreteScheduler(
+            shift=flow_shift,
+            reverse=self.args.flow_reverse,
+            solver=self.args.flow_solver
+        )
+        self.pipeline.scheduler = scheduler
+
+        # ========================================================================
+        # Build Rope freqs
+        # ========================================================================
+        freqs_cos, freqs_sin = self.get_rotary_pos_embed(
+            target_video_length, target_height, target_width
+        )
+        n_tokens = freqs_cos.shape[0]
+
+        # ========================================================================
+        # Print infer args
+        # ========================================================================
+        debug_str = f"""
+                        height: {target_height}
+                         width: {target_width}
+                  video_length: {target_video_length}
+                        prompt: {prompt}
+                    neg_prompt: {negative_prompt}
+                          seed: {seed}
+                   infer_steps: {infer_steps}
+         num_videos_per_prompt: {num_videos_per_prompt}
+                guidance_scale: {guidance_scale}
+                      n_tokens: {n_tokens}
+                    flow_shift: {flow_shift}
+       embedded_guidance_scale: {embedded_guidance_scale}"""
+        logger.debug(debug_str)
+
+        # ========================================================================
+        # Pipeline inference
+        # ========================================================================
+        start_time = time.time()
+        samples = self.pipeline(
+            prompt=prompt,
+            height=target_height,
+            width=target_width,
+            video_length=target_video_length,
+            num_inference_steps=infer_steps,
+            guidance_scale=guidance_scale,
+            negative_prompt=negative_prompt,
+            num_videos_per_prompt=num_videos_per_prompt,
+            generator=generator,
+            output_type="pil",
+            freqs_cis=(freqs_cos, freqs_sin),
+            n_tokens=n_tokens,
+            embedded_guidance_scale=embedded_guidance_scale,
+            data_type="video" if target_video_length > 1 else "image",
+            is_progress_bar=True,
+            vae_ver=self.args.vae,
+            enable_tiling=self.args.vae_tiling,
+        )[0]
+        out_dict["samples"] = samples
+        out_dict["prompts"] = prompt
+
+        gen_time = time.time() - start_time
+        logger.info(f"Success, time: {gen_time}")
+
+        return out_dict

hyvideo/modules/__init__.py

@@ -0,0 +1,26 @@
+from .models import HYVideoDiffusionTransformer, HUNYUAN_VIDEO_CONFIG
+
+
+def load_model(args, in_channels, out_channels, factor_kwargs):
+    """load hunyuan video model
+
+    Args:
+        args (dict): model args
+        in_channels (int): input channels number
+        out_channels (int): output channels number
+        factor_kwargs (dict): factor kwargs
+
+    Returns:
+        model (nn.Module): The hunyuan video model
+    """
+    if args.model in HUNYUAN_VIDEO_CONFIG.keys():
+        model = HYVideoDiffusionTransformer(
+            args,
+            in_channels=in_channels,
+            out_channels=out_channels,
+            **HUNYUAN_VIDEO_CONFIG[args.model],
+            **factor_kwargs,
+        )
+        return model
+    else:
+        raise NotImplementedError()

hyvideo/modules/activation_layers.py

@@ -0,0 +1,23 @@
+import torch.nn as nn
+
+
+def get_activation_layer(act_type):
+    """get activation layer
+
+    Args:
+        act_type (str): the activation type
+
+    Returns:
+        torch.nn.functional: the activation layer
+    """
+    if act_type == "gelu":
+        return lambda: nn.GELU()
+    elif act_type == "gelu_tanh":
+        # Approximate `tanh` requires torch >= 1.13
+        return lambda: nn.GELU(approximate="tanh")
+    elif act_type == "relu":
+        return nn.ReLU
+    elif act_type == "silu":
+        return nn.SiLU
+    else:
+        raise ValueError(f"Unknown activation type: {act_type}")

hyvideo/modules/attenion.py

@@ -0,0 +1,212 @@
+import importlib.metadata
+import math
+
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+
+try:
+    import flash_attn
+    from flash_attn.flash_attn_interface import _flash_attn_forward
+    from flash_attn.flash_attn_interface import flash_attn_varlen_func
+except ImportError:
+    flash_attn = None
+    flash_attn_varlen_func = None
+    _flash_attn_forward = None
+
+
+MEMORY_LAYOUT = {
+    "flash": (
+        lambda x: x.view(x.shape[0] * x.shape[1], *x.shape[2:]),
+        lambda x: x,
+    ),
+    "torch": (
+        lambda x: x.transpose(1, 2),
+        lambda x: x.transpose(1, 2),
+    ),
+    "vanilla": (
+        lambda x: x.transpose(1, 2),
+        lambda x: x.transpose(1, 2),
+    ),
+}
+
+
+def get_cu_seqlens(text_mask, img_len):
+    """Calculate cu_seqlens_q, cu_seqlens_kv using text_mask and img_len
+
+    Args:
+        text_mask (torch.Tensor): the mask of text
+        img_len (int): the length of image
+
+    Returns:
+        torch.Tensor: the calculated cu_seqlens for flash attention
+    """
+    batch_size = text_mask.shape[0]
+    text_len = text_mask.sum(dim=1)
+    max_len = text_mask.shape[1] + img_len
+
+    cu_seqlens = torch.zeros([2 * batch_size + 1], dtype=torch.int32, device="cuda")
+
+    for i in range(batch_size):
+        s = text_len[i] + img_len
+        s1 = i * max_len + s
+        s2 = (i + 1) * max_len
+        cu_seqlens[2 * i + 1] = s1
+        cu_seqlens[2 * i + 2] = s2
+
+    return cu_seqlens
+
+
+def attention(
+    q,
+    k,
+    v,
+    mode="flash",
+    drop_rate=0,
+    attn_mask=None,
+    causal=False,
+    cu_seqlens_q=None,
+    cu_seqlens_kv=None,
+    max_seqlen_q=None,
+    max_seqlen_kv=None,
+    batch_size=1,
+):
+    """
+    Perform QKV self attention.
+
+    Args:
+        q (torch.Tensor): Query tensor with shape [b, s, a, d], where a is the number of heads.
+        k (torch.Tensor): Key tensor with shape [b, s1, a, d]
+        v (torch.Tensor): Value tensor with shape [b, s1, a, d]
+        mode (str): Attention mode. Choose from 'self_flash', 'cross_flash', 'torch', and 'vanilla'.
+        drop_rate (float): Dropout rate in attention map. (default: 0)
+        attn_mask (torch.Tensor): Attention mask with shape [b, s1] (cross_attn), or [b, a, s, s1] (torch or vanilla).
+            (default: None)
+        causal (bool): Whether to use causal attention. (default: False)
+        cu_seqlens_q (torch.Tensor): dtype torch.int32. The cumulative sequence lengths of the sequences in the batch,
+            used to index into q.
+        cu_seqlens_kv (torch.Tensor): dtype torch.int32. The cumulative sequence lengths of the sequences in the batch,
+            used to index into kv.
+        max_seqlen_q (int): The maximum sequence length in the batch of q.
+        max_seqlen_kv (int): The maximum sequence length in the batch of k and v.
+
+    Returns:
+        torch.Tensor: Output tensor after self attention with shape [b, s, ad]
+    """
+    pre_attn_layout, post_attn_layout = MEMORY_LAYOUT[mode]
+    q = pre_attn_layout(q)
+    k = pre_attn_layout(k)
+    v = pre_attn_layout(v)
+
+    if mode == "torch":
+        if attn_mask is not None and attn_mask.dtype != torch.bool:
+            attn_mask = attn_mask.to(q.dtype)
+        x = F.scaled_dot_product_attention(
+            q, k, v, attn_mask=attn_mask, dropout_p=drop_rate, is_causal=causal
+        )
+    elif mode == "flash":
+        x = flash_attn_varlen_func(
+            q,
+            k,
+            v,
+            cu_seqlens_q,
+            cu_seqlens_kv,
+            max_seqlen_q,
+            max_seqlen_kv,
+        )
+        # x with shape [(bxs), a, d]
+        x = x.view(
+            batch_size, max_seqlen_q, x.shape[-2], x.shape[-1]
+        )  # reshape x to [b, s, a, d]
+    elif mode == "vanilla":
+        scale_factor = 1 / math.sqrt(q.size(-1))
+
+        b, a, s, _ = q.shape
+        s1 = k.size(2)
+        attn_bias = torch.zeros(b, a, s, s1, dtype=q.dtype, device=q.device)
+        if causal:
+            # Only applied to self attention
+            assert (
+                attn_mask is None
+            ), "Causal mask and attn_mask cannot be used together"
+            temp_mask = torch.ones(b, a, s, s, dtype=torch.bool, device=q.device).tril(
+                diagonal=0
+            )
+            attn_bias.masked_fill_(temp_mask.logical_not(), float("-inf"))
+            attn_bias.to(q.dtype)
+
+        if attn_mask is not None:
+            if attn_mask.dtype == torch.bool:
+                attn_bias.masked_fill_(attn_mask.logical_not(), float("-inf"))
+            else:
+                attn_bias += attn_mask
+
+        # TODO: Maybe force q and k to be float32 to avoid numerical overflow
+        attn = (q @ k.transpose(-2, -1)) * scale_factor
+        attn += attn_bias
+        attn = attn.softmax(dim=-1)
+        attn = torch.dropout(attn, p=drop_rate, train=True)
+        x = attn @ v
+    else:
+        raise NotImplementedError(f"Unsupported attention mode: {mode}")
+
+    x = post_attn_layout(x)
+    b, s, a, d = x.shape
+    out = x.reshape(b, s, -1)
+    return out
+
+
+def parallel_attention(
+    hybrid_seq_parallel_attn,
+    q,
+    k,
+    v,
+    img_q_len,
+    img_kv_len,
+    cu_seqlens_q,
+    cu_seqlens_kv
+):
+    attn1 = hybrid_seq_parallel_attn(
+        None,
+        q[:, :img_q_len, :, :],
+        k[:, :img_kv_len, :, :],
+        v[:, :img_kv_len, :, :],
+        dropout_p=0.0,
+        causal=False,
+        joint_tensor_query=q[:,img_q_len:cu_seqlens_q[1]],
+        joint_tensor_key=k[:,img_kv_len:cu_seqlens_kv[1]],
+        joint_tensor_value=v[:,img_kv_len:cu_seqlens_kv[1]],
+        joint_strategy="rear",
+    )
+    if flash_attn.__version__ >= '2.7.0':
+        attn2, *_ = _flash_attn_forward(
+            q[:,cu_seqlens_q[1]:],
+            k[:,cu_seqlens_kv[1]:],
+            v[:,cu_seqlens_kv[1]:],
+            dropout_p=0.0,
+            softmax_scale=q.shape[-1] ** (-0.5),
+            causal=False,
+            window_size_left=-1,
+            window_size_right=-1,
+            softcap=0.0,
+            alibi_slopes=None,
+            return_softmax=False,
+        )
+    else:
+        attn2, *_ = _flash_attn_forward(
+            q[:,cu_seqlens_q[1]:],
+            k[:,cu_seqlens_kv[1]:],
+            v[:,cu_seqlens_kv[1]:],
+            dropout_p=0.0,
+            softmax_scale=q.shape[-1] ** (-0.5),
+            causal=False,
+            window_size=(-1, -1),
+            softcap=0.0,
+            alibi_slopes=None,
+            return_softmax=False,
+        )
+    attn = torch.cat([attn1, attn2], dim=1)
+    b, s, a, d = attn.shape
+    attn = attn.reshape(b, s, -1)
+
+    return attn

hyvideo/modules/embed_layers.py

@@ -0,0 +1,157 @@
+import math
+import torch
+import torch.nn as nn
+from einops import rearrange, repeat
+
+from ..utils.helpers import to_2tuple
+
+
+class PatchEmbed(nn.Module):
+    """2D Image to Patch Embedding
+
+    Image to Patch Embedding using Conv2d
+
+    A convolution based approach to patchifying a 2D image w/ embedding projection.
+
+    Based on the impl in https://github.com/google-research/vision_transformer
+
+    Hacked together by / Copyright 2020 Ross Wightman
+
+    Remove the _assert function in forward function to be compatible with multi-resolution images.
+    """
+
+    def __init__(
+        self,
+        patch_size=16,
+        in_chans=3,
+        embed_dim=768,
+        norm_layer=None,
+        flatten=True,
+        bias=True,
+        dtype=None,
+        device=None,
+    ):
+        factory_kwargs = {"dtype": dtype, "device": device}
+        super().__init__()
+        patch_size = to_2tuple(patch_size)
+        self.patch_size = patch_size
+        self.flatten = flatten
+
+        self.proj = nn.Conv3d(
+            in_chans,
+            embed_dim,
+            kernel_size=patch_size,
+            stride=patch_size,
+            bias=bias,
+            **factory_kwargs
+        )
+        nn.init.xavier_uniform_(self.proj.weight.view(self.proj.weight.size(0), -1))
+        if bias:
+            nn.init.zeros_(self.proj.bias)
+
+        self.norm = norm_layer(embed_dim) if norm_layer else nn.Identity()
+
+    def forward(self, x):
+        x = self.proj(x)
+        if self.flatten:
+            x = x.flatten(2).transpose(1, 2)  # BCHW -> BNC
+        x = self.norm(x)
+        return x
+
+
+class TextProjection(nn.Module):
+    """
+    Projects text embeddings. Also handles dropout for classifier-free guidance.
+
+    Adapted from https://github.com/PixArt-alpha/PixArt-alpha/blob/master/diffusion/model/nets/PixArt_blocks.py
+    """
+
+    def __init__(self, in_channels, hidden_size, act_layer, dtype=None, device=None):
+        factory_kwargs = {"dtype": dtype, "device": device}
+        super().__init__()
+        self.linear_1 = nn.Linear(
+            in_features=in_channels,
+            out_features=hidden_size,
+            bias=True,
+            **factory_kwargs
+        )
+        self.act_1 = act_layer()
+        self.linear_2 = nn.Linear(
+            in_features=hidden_size,
+            out_features=hidden_size,
+            bias=True,
+            **factory_kwargs
+        )
+
+    def forward(self, caption):
+        hidden_states = self.linear_1(caption)
+        hidden_states = self.act_1(hidden_states)
+        hidden_states = self.linear_2(hidden_states)
+        return hidden_states
+
+
+def timestep_embedding(t, dim, max_period=10000):
+    """
+    Create sinusoidal timestep embeddings.
+
+    Args:
+        t (torch.Tensor): a 1-D Tensor of N indices, one per batch element. These may be fractional.
+        dim (int): the dimension of the output.
+        max_period (int): controls the minimum frequency of the embeddings.
+
+    Returns:
+        embedding (torch.Tensor): An (N, D) Tensor of positional embeddings.
+
+    .. ref_link: https://github.com/openai/glide-text2im/blob/main/glide_text2im/nn.py
+    """
+    half = dim // 2
+    freqs = torch.exp(
+        -math.log(max_period)
+        * torch.arange(start=0, end=half, dtype=torch.float32)
+        / half
+    ).to(device=t.device)
+    args = t[:, None].float() * freqs[None]
+    embedding = torch.cat([torch.cos(args), torch.sin(args)], dim=-1)
+    if dim % 2:
+        embedding = torch.cat([embedding, torch.zeros_like(embedding[:, :1])], dim=-1)
+    return embedding
+
+
+class TimestepEmbedder(nn.Module):
+    """
+    Embeds scalar timesteps into vector representations.
+    """
+
+    def __init__(
+        self,
+        hidden_size,
+        act_layer,
+        frequency_embedding_size=256,
+        max_period=10000,
+        out_size=None,
+        dtype=None,
+        device=None,
+    ):
+        factory_kwargs = {"dtype": dtype, "device": device}
+        super().__init__()
+        self.frequency_embedding_size = frequency_embedding_size
+        self.max_period = max_period
+        if out_size is None:
+            out_size = hidden_size
+
+        self.mlp = nn.Sequential(
+            nn.Linear(
+                frequency_embedding_size, hidden_size, bias=True, **factory_kwargs
+            ),
+            act_layer(),
+            nn.Linear(hidden_size, out_size, bias=True, **factory_kwargs),
+        )
+        nn.init.normal_(self.mlp[0].weight, std=0.02)
+        nn.init.normal_(self.mlp[2].weight, std=0.02)
+
+    def forward(self, t):
+        t_freq = timestep_embedding(
+            t, self.frequency_embedding_size, self.max_period
+        ).type(self.mlp[0].weight.dtype)
+        t_emb = self.mlp(t_freq)
+        return t_emb

hyvideo/modules/mlp_layers.py

@@ -0,0 +1,118 @@
+# Modified from timm library:
+# https://github.com/huggingface/pytorch-image-models/blob/648aaa41233ba83eb38faf5ba9d415d574823241/timm/layers/mlp.py#L13
+
+from functools import partial
+
+import torch
+import torch.nn as nn
+
+from .modulate_layers import modulate
+from ..utils.helpers import to_2tuple
+
+
+class MLP(nn.Module):
+    """MLP as used in Vision Transformer, MLP-Mixer and related networks"""
+
+    def __init__(
+        self,
+        in_channels,
+        hidden_channels=None,
+        out_features=None,
+        act_layer=nn.GELU,
+        norm_layer=None,
+        bias=True,
+        drop=0.0,
+        use_conv=False,
+        device=None,
+        dtype=None,
+    ):
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+        out_features = out_features or in_channels
+        hidden_channels = hidden_channels or in_channels
+        bias = to_2tuple(bias)
+        drop_probs = to_2tuple(drop)
+        linear_layer = partial(nn.Conv2d, kernel_size=1) if use_conv else nn.Linear
+
+        self.fc1 = linear_layer(
+            in_channels, hidden_channels, bias=bias[0], **factory_kwargs
+        )
+        self.act = act_layer()
+        self.drop1 = nn.Dropout(drop_probs[0])
+        self.norm = (
+            norm_layer(hidden_channels, **factory_kwargs)
+            if norm_layer is not None
+            else nn.Identity()
+        )
+        self.fc2 = linear_layer(
+            hidden_channels, out_features, bias=bias[1], **factory_kwargs
+        )
+        self.drop2 = nn.Dropout(drop_probs[1])
+
+    def forward(self, x):
+        x = self.fc1(x)
+        x = self.act(x)
+        x = self.drop1(x)
+        x = self.norm(x)
+        x = self.fc2(x)
+        x = self.drop2(x)
+        return x
+
+
+# 
+class MLPEmbedder(nn.Module):
+    """copied from https://github.com/black-forest-labs/flux/blob/main/src/flux/modules/layers.py"""
+    def __init__(self, in_dim: int, hidden_dim: int, device=None, dtype=None):
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+        self.in_layer = nn.Linear(in_dim, hidden_dim, bias=True, **factory_kwargs)
+        self.silu = nn.SiLU()
+        self.out_layer = nn.Linear(hidden_dim, hidden_dim, bias=True, **factory_kwargs)
+
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        return self.out_layer(self.silu(self.in_layer(x)))
+
+
+class FinalLayer(nn.Module):
+    """The final layer of DiT."""
+
+    def __init__(
+        self, hidden_size, patch_size, out_channels, act_layer, device=None, dtype=None
+    ):
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+
+        # Just use LayerNorm for the final layer
+        self.norm_final = nn.LayerNorm(
+            hidden_size, elementwise_affine=False, eps=1e-6, **factory_kwargs
+        )
+        if isinstance(patch_size, int):
+            self.linear = nn.Linear(
+                hidden_size,
+                patch_size * patch_size * out_channels,
+                bias=True,
+                **factory_kwargs
+            )
+        else:
+            self.linear = nn.Linear(
+                hidden_size,
+                patch_size[0] * patch_size[1] * patch_size[2] * out_channels,
+                bias=True,
+            )
+        nn.init.zeros_(self.linear.weight)
+        nn.init.zeros_(self.linear.bias)
+
+        # Here we don't distinguish between the modulate types. Just use the simple one.
+        self.adaLN_modulation = nn.Sequential(
+            act_layer(),
+            nn.Linear(hidden_size, 2 * hidden_size, bias=True, **factory_kwargs),
+        )
+        # Zero-initialize the modulation
+        nn.init.zeros_(self.adaLN_modulation[1].weight)
+        nn.init.zeros_(self.adaLN_modulation[1].bias)
+
+    def forward(self, x, c):
+        shift, scale = self.adaLN_modulation(c).chunk(2, dim=1)
+        x = modulate(self.norm_final(x), shift=shift, scale=scale)
+        x = self.linear(x)
+        return x

hyvideo/modules/models.py

@@ -0,0 +1,760 @@
+from typing import Any, List, Tuple, Optional, Union, Dict
+from einops import rearrange
+
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+
+from diffusers.models import ModelMixin
+from diffusers.configuration_utils import ConfigMixin, register_to_config
+
+from .activation_layers import get_activation_layer
+from .norm_layers import get_norm_layer
+from .embed_layers import TimestepEmbedder, PatchEmbed, TextProjection
+from .attenion import attention, parallel_attention, get_cu_seqlens
+from .posemb_layers import apply_rotary_emb
+from .mlp_layers import MLP, MLPEmbedder, FinalLayer
+from .modulate_layers import ModulateDiT, modulate, apply_gate
+from .token_refiner import SingleTokenRefiner
+
+
+class MMDoubleStreamBlock(nn.Module):
+    """
+    A multimodal dit block with seperate modulation for
+    text and image/video, see more details (SD3): https://arxiv.org/abs/2403.03206
+                                     (Flux.1): https://github.com/black-forest-labs/flux
+    """
+
+    def __init__(
+        self,
+        hidden_size: int,
+        heads_num: int,
+        mlp_width_ratio: float,
+        mlp_act_type: str = "gelu_tanh",
+        qk_norm: bool = True,
+        qk_norm_type: str = "rms",
+        qkv_bias: bool = False,
+        dtype: Optional[torch.dtype] = None,
+        device: Optional[torch.device] = None,
+    ):
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+
+        self.deterministic = False
+        self.heads_num = heads_num
+        head_dim = hidden_size // heads_num
+        mlp_hidden_dim = int(hidden_size * mlp_width_ratio)
+
+        self.img_mod = ModulateDiT(
+            hidden_size,
+            factor=6,
+            act_layer=get_activation_layer("silu"),
+            **factory_kwargs,
+        )
+        self.img_norm1 = nn.LayerNorm(
+            hidden_size, elementwise_affine=False, eps=1e-6, **factory_kwargs
+        )
+
+        self.img_attn_qkv = nn.Linear(
+            hidden_size, hidden_size * 3, bias=qkv_bias, **factory_kwargs
+        )
+        qk_norm_layer = get_norm_layer(qk_norm_type)
+        self.img_attn_q_norm = (
+            qk_norm_layer(head_dim, elementwise_affine=True, eps=1e-6, **factory_kwargs)
+            if qk_norm
+            else nn.Identity()
+        )
+        self.img_attn_k_norm = (
+            qk_norm_layer(head_dim, elementwise_affine=True, eps=1e-6, **factory_kwargs)
+            if qk_norm
+            else nn.Identity()
+        )
+        self.img_attn_proj = nn.Linear(
+            hidden_size, hidden_size, bias=qkv_bias, **factory_kwargs
+        )
+
+        self.img_norm2 = nn.LayerNorm(
+            hidden_size, elementwise_affine=False, eps=1e-6, **factory_kwargs
+        )
+        self.img_mlp = MLP(
+            hidden_size,
+            mlp_hidden_dim,
+            act_layer=get_activation_layer(mlp_act_type),
+            bias=True,
+            **factory_kwargs,
+        )
+
+        self.txt_mod = ModulateDiT(
+            hidden_size,
+            factor=6,
+            act_layer=get_activation_layer("silu"),
+            **factory_kwargs,
+        )
+        self.txt_norm1 = nn.LayerNorm(
+            hidden_size, elementwise_affine=False, eps=1e-6, **factory_kwargs
+        )
+
+        self.txt_attn_qkv = nn.Linear(
+            hidden_size, hidden_size * 3, bias=qkv_bias, **factory_kwargs
+        )
+        self.txt_attn_q_norm = (
+            qk_norm_layer(head_dim, elementwise_affine=True, eps=1e-6, **factory_kwargs)
+            if qk_norm
+            else nn.Identity()
+        )
+        self.txt_attn_k_norm = (
+            qk_norm_layer(head_dim, elementwise_affine=True, eps=1e-6, **factory_kwargs)
+            if qk_norm
+            else nn.Identity()
+        )
+        self.txt_attn_proj = nn.Linear(
+            hidden_size, hidden_size, bias=qkv_bias, **factory_kwargs
+        )
+
+        self.txt_norm2 = nn.LayerNorm(
+            hidden_size, elementwise_affine=False, eps=1e-6, **factory_kwargs
+        )
+        self.txt_mlp = MLP(
+            hidden_size,
+            mlp_hidden_dim,
+            act_layer=get_activation_layer(mlp_act_type),
+            bias=True,
+            **factory_kwargs,
+        )
+        self.hybrid_seq_parallel_attn = None
+
+    def enable_deterministic(self):
+        self.deterministic = True
+
+    def disable_deterministic(self):
+        self.deterministic = False
+
+    def forward(
+        self,
+        img: torch.Tensor,
+        txt: torch.Tensor,
+        vec: torch.Tensor,
+        cu_seqlens_q: Optional[torch.Tensor] = None,
+        cu_seqlens_kv: Optional[torch.Tensor] = None,
+        max_seqlen_q: Optional[int] = None,
+        max_seqlen_kv: Optional[int] = None,
+        freqs_cis: tuple = None,
+    ) -> Tuple[torch.Tensor, torch.Tensor]:
+        (
+            img_mod1_shift,
+            img_mod1_scale,
+            img_mod1_gate,
+            img_mod2_shift,
+            img_mod2_scale,
+            img_mod2_gate,
+        ) = self.img_mod(vec).chunk(6, dim=-1)
+        (
+            txt_mod1_shift,
+            txt_mod1_scale,
+            txt_mod1_gate,
+            txt_mod2_shift,
+            txt_mod2_scale,
+            txt_mod2_gate,
+        ) = self.txt_mod(vec).chunk(6, dim=-1)
+
+        # Prepare image for attention.
+        img_modulated = self.img_norm1(img)
+        img_modulated = modulate(
+            img_modulated, shift=img_mod1_shift, scale=img_mod1_scale
+        )
+        img_qkv = self.img_attn_qkv(img_modulated)
+        img_q, img_k, img_v = rearrange(
+            img_qkv, "B L (K H D) -> K B L H D", K=3, H=self.heads_num
+        )
+        # Apply QK-Norm if needed
+        img_q = self.img_attn_q_norm(img_q).to(img_v)
+        img_k = self.img_attn_k_norm(img_k).to(img_v)
+
+        # Apply RoPE if needed.
+        if freqs_cis is not None:
+            img_qq, img_kk = apply_rotary_emb(img_q, img_k, freqs_cis, head_first=False)
+            assert (
+                img_qq.shape == img_q.shape and img_kk.shape == img_k.shape
+            ), f"img_kk: {img_qq.shape}, img_q: {img_q.shape}, img_kk: {img_kk.shape}, img_k: {img_k.shape}"
+            img_q, img_k = img_qq, img_kk
+
+        # Prepare txt for attention.
+        txt_modulated = self.txt_norm1(txt)
+        txt_modulated = modulate(
+            txt_modulated, shift=txt_mod1_shift, scale=txt_mod1_scale
+        )
+        txt_qkv = self.txt_attn_qkv(txt_modulated)
+        txt_q, txt_k, txt_v = rearrange(
+            txt_qkv, "B L (K H D) -> K B L H D", K=3, H=self.heads_num
+        )
+        # Apply QK-Norm if needed.
+        txt_q = self.txt_attn_q_norm(txt_q).to(txt_v)
+        txt_k = self.txt_attn_k_norm(txt_k).to(txt_v)
+
+        # Run actual attention.
+        q = torch.cat((img_q, txt_q), dim=1)
+        k = torch.cat((img_k, txt_k), dim=1)
+        v = torch.cat((img_v, txt_v), dim=1)
+        assert (
+            cu_seqlens_q.shape[0] == 2 * img.shape[0] + 1
+        ), f"cu_seqlens_q.shape:{cu_seqlens_q.shape}, img.shape[0]:{img.shape[0]}"
+        
+        # attention computation start
+        if not self.hybrid_seq_parallel_attn:
+            attn = attention(
+                q,
+                k,
+                v,
+                cu_seqlens_q=cu_seqlens_q,
+                cu_seqlens_kv=cu_seqlens_kv,
+                max_seqlen_q=max_seqlen_q,
+                max_seqlen_kv=max_seqlen_kv,
+                batch_size=img_k.shape[0],
+            )
+        else:
+            attn = parallel_attention(
+                self.hybrid_seq_parallel_attn,
+                q,
+                k,
+                v,
+                img_q_len=img_q.shape[1],
+                img_kv_len=img_k.shape[1],
+                cu_seqlens_q=cu_seqlens_q,
+                cu_seqlens_kv=cu_seqlens_kv
+            )
+            
+        # attention computation end
+
+        img_attn, txt_attn = attn[:, : img.shape[1]], attn[:, img.shape[1] :]
+
+        # Calculate the img bloks.
+        img = img + apply_gate(self.img_attn_proj(img_attn), gate=img_mod1_gate)
+        img = img + apply_gate(
+            self.img_mlp(
+                modulate(
+                    self.img_norm2(img), shift=img_mod2_shift, scale=img_mod2_scale
+                )
+            ),
+            gate=img_mod2_gate,
+        )
+
+        # Calculate the txt bloks.
+        txt = txt + apply_gate(self.txt_attn_proj(txt_attn), gate=txt_mod1_gate)
+        txt = txt + apply_gate(
+            self.txt_mlp(
+                modulate(
+                    self.txt_norm2(txt), shift=txt_mod2_shift, scale=txt_mod2_scale
+                )
+            ),
+            gate=txt_mod2_gate,
+        )
+
+        return img, txt
+
+
+class MMSingleStreamBlock(nn.Module):
+    """
+    A DiT block with parallel linear layers as described in
+    https://arxiv.org/abs/2302.05442 and adapted modulation interface.
+    Also refer to (SD3): https://arxiv.org/abs/2403.03206
+                  (Flux.1): https://github.com/black-forest-labs/flux
+    """
+
+    def __init__(
+        self,
+        hidden_size: int,
+        heads_num: int,
+        mlp_width_ratio: float = 4.0,
+        mlp_act_type: str = "gelu_tanh",
+        qk_norm: bool = True,
+        qk_norm_type: str = "rms",
+        qk_scale: float = None,
+        dtype: Optional[torch.dtype] = None,
+        device: Optional[torch.device] = None,
+    ):
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+
+        self.deterministic = False
+        self.hidden_size = hidden_size
+        self.heads_num = heads_num
+        head_dim = hidden_size // heads_num
+        mlp_hidden_dim = int(hidden_size * mlp_width_ratio)
+        self.mlp_hidden_dim = mlp_hidden_dim
+        self.scale = qk_scale or head_dim ** -0.5
+
+        # qkv and mlp_in
+        self.linear1 = nn.Linear(
+            hidden_size, hidden_size * 3 + mlp_hidden_dim, **factory_kwargs
+        )
+        # proj and mlp_out
+        self.linear2 = nn.Linear(
+            hidden_size + mlp_hidden_dim, hidden_size, **factory_kwargs
+        )
+
+        qk_norm_layer = get_norm_layer(qk_norm_type)
+        self.q_norm = (
+            qk_norm_layer(head_dim, elementwise_affine=True, eps=1e-6, **factory_kwargs)
+            if qk_norm
+            else nn.Identity()
+        )
+        self.k_norm = (
+            qk_norm_layer(head_dim, elementwise_affine=True, eps=1e-6, **factory_kwargs)
+            if qk_norm
+            else nn.Identity()
+        )
+
+        self.pre_norm = nn.LayerNorm(
+            hidden_size, elementwise_affine=False, eps=1e-6, **factory_kwargs
+        )
+
+        self.mlp_act = get_activation_layer(mlp_act_type)()
+        self.modulation = ModulateDiT(
+            hidden_size,
+            factor=3,
+            act_layer=get_activation_layer("silu"),
+            **factory_kwargs,
+        )
+        self.hybrid_seq_parallel_attn = None
+
+    def enable_deterministic(self):
+        self.deterministic = True
+
+    def disable_deterministic(self):
+        self.deterministic = False
+
+    def forward(
+        self,
+        x: torch.Tensor,
+        vec: torch.Tensor,
+        txt_len: int,
+        cu_seqlens_q: Optional[torch.Tensor] = None,
+        cu_seqlens_kv: Optional[torch.Tensor] = None,
+        max_seqlen_q: Optional[int] = None,
+        max_seqlen_kv: Optional[int] = None,
+        freqs_cis: Tuple[torch.Tensor, torch.Tensor] = None,
+    ) -> torch.Tensor:
+        mod_shift, mod_scale, mod_gate = self.modulation(vec).chunk(3, dim=-1)
+        x_mod = modulate(self.pre_norm(x), shift=mod_shift, scale=mod_scale)
+        qkv, mlp = torch.split(
+            self.linear1(x_mod), [3 * self.hidden_size, self.mlp_hidden_dim], dim=-1
+        )
+
+        q, k, v = rearrange(qkv, "B L (K H D) -> K B L H D", K=3, H=self.heads_num)
+
+        # Apply QK-Norm if needed.
+        q = self.q_norm(q).to(v)
+        k = self.k_norm(k).to(v)
+
+        # Apply RoPE if needed.
+        if freqs_cis is not None:
+            img_q, txt_q = q[:, :-txt_len, :, :], q[:, -txt_len:, :, :]
+            img_k, txt_k = k[:, :-txt_len, :, :], k[:, -txt_len:, :, :]
+            img_qq, img_kk = apply_rotary_emb(img_q, img_k, freqs_cis, head_first=False)
+            assert (
+                img_qq.shape == img_q.shape and img_kk.shape == img_k.shape
+            ), f"img_kk: {img_qq.shape}, img_q: {img_q.shape}, img_kk: {img_kk.shape}, img_k: {img_k.shape}"
+            img_q, img_k = img_qq, img_kk
+            q = torch.cat((img_q, txt_q), dim=1)
+            k = torch.cat((img_k, txt_k), dim=1)
+
+        # Compute attention.
+        assert (
+            cu_seqlens_q.shape[0] == 2 * x.shape[0] + 1
+        ), f"cu_seqlens_q.shape:{cu_seqlens_q.shape}, x.shape[0]:{x.shape[0]}"
+        
+        # attention computation start
+        if not self.hybrid_seq_parallel_attn:
+            attn = attention(
+                q,
+                k,
+                v,
+                cu_seqlens_q=cu_seqlens_q,
+                cu_seqlens_kv=cu_seqlens_kv,
+                max_seqlen_q=max_seqlen_q,
+                max_seqlen_kv=max_seqlen_kv,
+                batch_size=x.shape[0],
+            )
+        else:
+            attn = parallel_attention(
+                self.hybrid_seq_parallel_attn,
+                q,
+                k,
+                v,
+                img_q_len=img_q.shape[1],
+                img_kv_len=img_k.shape[1],
+                cu_seqlens_q=cu_seqlens_q,
+                cu_seqlens_kv=cu_seqlens_kv
+            )
+        # attention computation end
+
+        # Compute activation in mlp stream, cat again and run second linear layer.
+        output = self.linear2(torch.cat((attn, self.mlp_act(mlp)), 2))
+        return x + apply_gate(output, gate=mod_gate)
+
+
+class HYVideoDiffusionTransformer(ModelMixin, ConfigMixin):
+    """
+    HunyuanVideo Transformer backbone
+
+    Inherited from ModelMixin and ConfigMixin for compatibility with diffusers' sampler StableDiffusionPipeline.
+
+    Reference:
+    [1] Flux.1: https://github.com/black-forest-labs/flux
+    [2] MMDiT: http://arxiv.org/abs/2403.03206
+
+    Parameters
+    ----------
+    args: argparse.Namespace
+        The arguments parsed by argparse.
+    patch_size: list
+        The size of the patch.
+    in_channels: int
+        The number of input channels.
+    out_channels: int
+        The number of output channels.
+    hidden_size: int
+        The hidden size of the transformer backbone.
+    heads_num: int
+        The number of attention heads.
+    mlp_width_ratio: float
+        The ratio of the hidden size of the MLP in the transformer block.
+    mlp_act_type: str
+        The activation function of the MLP in the transformer block.
+    depth_double_blocks: int
+        The number of transformer blocks in the double blocks.
+    depth_single_blocks: int
+        The number of transformer blocks in the single blocks.
+    rope_dim_list: list
+        The dimension of the rotary embedding for t, h, w.
+    qkv_bias: bool
+        Whether to use bias in the qkv linear layer.
+    qk_norm: bool
+        Whether to use qk norm.
+    qk_norm_type: str
+        The type of qk norm.
+    guidance_embed: bool
+        Whether to use guidance embedding for distillation.
+    text_projection: str
+        The type of the text projection, default is single_refiner.
+    use_attention_mask: bool
+        Whether to use attention mask for text encoder.
+    dtype: torch.dtype
+        The dtype of the model.
+    device: torch.device
+        The device of the model.
+    """
+
+    @register_to_config
+    def __init__(
+        self,
+        args: Any,
+        patch_size: list = [1, 2, 2],
+        in_channels: int = 4,  # Should be VAE.config.latent_channels.
+        out_channels: int = None,
+        hidden_size: int = 3072,
+        heads_num: int = 24,
+        mlp_width_ratio: float = 4.0,
+        mlp_act_type: str = "gelu_tanh",
+        mm_double_blocks_depth: int = 20,
+        mm_single_blocks_depth: int = 40,
+        rope_dim_list: List[int] = [16, 56, 56],
+        qkv_bias: bool = True,
+        qk_norm: bool = True,
+        qk_norm_type: str = "rms",
+        guidance_embed: bool = False,  # For modulation.
+        text_projection: str = "single_refiner",
+        use_attention_mask: bool = True,
+        dtype: Optional[torch.dtype] = None,
+        device: Optional[torch.device] = None,
+    ):
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+
+        self.patch_size = patch_size
+        self.in_channels = in_channels
+        self.out_channels = in_channels if out_channels is None else out_channels
+        self.unpatchify_channels = self.out_channels
+        self.guidance_embed = guidance_embed
+        self.rope_dim_list = rope_dim_list
+
+        # Text projection. Default to linear projection.
+        # Alternative: TokenRefiner. See more details (LI-DiT): http://arxiv.org/abs/2406.11831
+        self.use_attention_mask = use_attention_mask
+        self.text_projection = text_projection
+
+        self.text_states_dim = args.text_states_dim
+        self.text_states_dim_2 = args.text_states_dim_2
+
+        if hidden_size % heads_num != 0:
+            raise ValueError(
+                f"Hidden size {hidden_size} must be divisible by heads_num {heads_num}"
+            )
+        pe_dim = hidden_size // heads_num
+        if sum(rope_dim_list) != pe_dim:
+            raise ValueError(
+                f"Got {rope_dim_list} but expected positional dim {pe_dim}"
+            )
+        self.hidden_size = hidden_size
+        self.heads_num = heads_num
+
+        # image projection
+        self.img_in = PatchEmbed(
+            self.patch_size, self.in_channels, self.hidden_size, **factory_kwargs
+        )
+
+        # text projection
+        if self.text_projection == "linear":
+            self.txt_in = TextProjection(
+                self.text_states_dim,
+                self.hidden_size,
+                get_activation_layer("silu"),
+                **factory_kwargs,
+            )
+        elif self.text_projection == "single_refiner":
+            self.txt_in = SingleTokenRefiner(
+                self.text_states_dim, hidden_size, heads_num, depth=2, **factory_kwargs
+            )
+        else:
+            raise NotImplementedError(
+                f"Unsupported text_projection: {self.text_projection}"
+            )
+
+        # time modulation
+        self.time_in = TimestepEmbedder(
+            self.hidden_size, get_activation_layer("silu"), **factory_kwargs
+        )
+
+        # text modulation
+        self.vector_in = MLPEmbedder(
+            self.text_states_dim_2, self.hidden_size, **factory_kwargs
+        )
+
+        # guidance modulation
+        self.guidance_in = (
+            TimestepEmbedder(
+                self.hidden_size, get_activation_layer("silu"), **factory_kwargs
+            )
+            if guidance_embed
+            else None
+        )
+
+        # double blocks
+        self.double_blocks = nn.ModuleList(
+            [
+                MMDoubleStreamBlock(
+                    self.hidden_size,
+                    self.heads_num,
+                    mlp_width_ratio=mlp_width_ratio,
+                    mlp_act_type=mlp_act_type,
+                    qk_norm=qk_norm,
+                    qk_norm_type=qk_norm_type,
+                    qkv_bias=qkv_bias,
+                    **factory_kwargs,
+                )
+                for _ in range(mm_double_blocks_depth)
+            ]
+        )
+
+        # single blocks
+        self.single_blocks = nn.ModuleList(
+            [
+                MMSingleStreamBlock(
+                    self.hidden_size,
+                    self.heads_num,
+                    mlp_width_ratio=mlp_width_ratio,
+                    mlp_act_type=mlp_act_type,
+                    qk_norm=qk_norm,
+                    qk_norm_type=qk_norm_type,
+                    **factory_kwargs,
+                )
+                for _ in range(mm_single_blocks_depth)
+            ]
+        )
+
+        self.final_layer = FinalLayer(
+            self.hidden_size,
+            self.patch_size,
+            self.out_channels,
+            get_activation_layer("silu"),
+            **factory_kwargs,
+        )
+
+    def enable_deterministic(self):
+        for block in self.double_blocks:
+            block.enable_deterministic()
+        for block in self.single_blocks:
+            block.enable_deterministic()
+
+    def disable_deterministic(self):
+        for block in self.double_blocks:
+            block.disable_deterministic()
+        for block in self.single_blocks:
+            block.disable_deterministic()
+
+    def forward(
+        self,
+        x: torch.Tensor,
+        t: torch.Tensor,  # Should be in range(0, 1000).
+        text_states: torch.Tensor = None,
+        text_mask: torch.Tensor = None,  # Now we don't use it.
+        text_states_2: Optional[torch.Tensor] = None,  # Text embedding for modulation.
+        freqs_cos: Optional[torch.Tensor] = None,
+        freqs_sin: Optional[torch.Tensor] = None,
+        guidance: torch.Tensor = None,  # Guidance for modulation, should be cfg_scale x 1000.
+        return_dict: bool = True,
+    ) -> Union[torch.Tensor, Dict[str, torch.Tensor]]:
+        out = {}
+        img = x
+        txt = text_states
+        _, _, ot, oh, ow = x.shape
+        tt, th, tw = (
+            ot // self.patch_size[0],
+            oh // self.patch_size[1],
+            ow // self.patch_size[2],
+        )
+
+        # Prepare modulation vectors.
+        vec = self.time_in(t)
+
+        # text modulation
+        vec = vec + self.vector_in(text_states_2)
+
+        # guidance modulation
+        if self.guidance_embed:
+            if guidance is None:
+                raise ValueError(
+                    "Didn't get guidance strength for guidance distilled model."
+                )
+
+            # our timestep_embedding is merged into guidance_in(TimestepEmbedder)
+            vec = vec + self.guidance_in(guidance)
+
+        # Embed image and text.
+        img = self.img_in(img)
+        if self.text_projection == "linear":
+            txt = self.txt_in(txt)
+        elif self.text_projection == "single_refiner":
+            txt = self.txt_in(txt, t, text_mask if self.use_attention_mask else None)
+        else:
+            raise NotImplementedError(
+                f"Unsupported text_projection: {self.text_projection}"
+            )
+
+        txt_seq_len = txt.shape[1]
+        img_seq_len = img.shape[1]
+
+        # Compute cu_squlens and max_seqlen for flash attention
+        cu_seqlens_q = get_cu_seqlens(text_mask, img_seq_len)
+        cu_seqlens_kv = cu_seqlens_q
+        max_seqlen_q = img_seq_len + txt_seq_len
+        max_seqlen_kv = max_seqlen_q
+
+        freqs_cis = (freqs_cos, freqs_sin) if freqs_cos is not None else None
+        # --------------------- Pass through DiT blocks ------------------------
+        for _, block in enumerate(self.double_blocks):
+            double_block_args = [
+                img,
+                txt,
+                vec,
+                cu_seqlens_q,
+                cu_seqlens_kv,
+                max_seqlen_q,
+                max_seqlen_kv,
+                freqs_cis,
+            ]
+
+            img, txt = block(*double_block_args)
+
+        # Merge txt and img to pass through single stream blocks.
+        x = torch.cat((img, txt), 1)
+        if len(self.single_blocks) > 0:
+            for _, block in enumerate(self.single_blocks):
+                single_block_args = [
+                    x,
+                    vec,
+                    txt_seq_len,
+                    cu_seqlens_q,
+                    cu_seqlens_kv,
+                    max_seqlen_q,
+                    max_seqlen_kv,
+                    (freqs_cos, freqs_sin),
+                ]
+
+                x = block(*single_block_args)
+
+        img = x[:, :img_seq_len, ...]
+
+        # ---------------------------- Final layer ------------------------------
+        img = self.final_layer(img, vec)  # (N, T, patch_size ** 2 * out_channels)
+
+        img = self.unpatchify(img, tt, th, tw)
+        if return_dict:
+            out["x"] = img
+            return out
+        return img
+
+    def unpatchify(self, x, t, h, w):
+        """
+        x: (N, T, patch_size**2 * C)
+        imgs: (N, H, W, C)
+        """
+        c = self.unpatchify_channels
+        pt, ph, pw = self.patch_size
+        assert t * h * w == x.shape[1]
+
+        x = x.reshape(shape=(x.shape[0], t, h, w, c, pt, ph, pw))
+        x = torch.einsum("nthwcopq->nctohpwq", x)
+        imgs = x.reshape(shape=(x.shape[0], c, t * pt, h * ph, w * pw))
+
+        return imgs
+
+    def params_count(self):
+        counts = {
+            "double": sum(
+                [
+                    sum(p.numel() for p in block.img_attn_qkv.parameters())
+                    + sum(p.numel() for p in block.img_attn_proj.parameters())
+                    + sum(p.numel() for p in block.img_mlp.parameters())
+                    + sum(p.numel() for p in block.txt_attn_qkv.parameters())
+                    + sum(p.numel() for p in block.txt_attn_proj.parameters())
+                    + sum(p.numel() for p in block.txt_mlp.parameters())
+                    for block in self.double_blocks
+                ]
+            ),
+            "single": sum(
+                [
+                    sum(p.numel() for p in block.linear1.parameters())
+                    + sum(p.numel() for p in block.linear2.parameters())
+                    for block in self.single_blocks
+                ]
+            ),
+            "total": sum(p.numel() for p in self.parameters()),
+        }
+        counts["attn+mlp"] = counts["double"] + counts["single"]
+        return counts
+
+
+#################################################################################
+#                             HunyuanVideo Configs                              #
+#################################################################################
+
+HUNYUAN_VIDEO_CONFIG = {
+    "HYVideo-T/2": {
+        "mm_double_blocks_depth": 20,
+        "mm_single_blocks_depth": 40,
+        "rope_dim_list": [16, 56, 56],
+        "hidden_size": 3072,
+        "heads_num": 24,
+        "mlp_width_ratio": 4,
+    },
+    "HYVideo-T/2-cfgdistill": {
+        "mm_double_blocks_depth": 20,
+        "mm_single_blocks_depth": 40,
+        "rope_dim_list": [16, 56, 56],
+        "hidden_size": 3072,
+        "heads_num": 24,
+        "mlp_width_ratio": 4,
+        "guidance_embed": True,
+    },
+}

hyvideo/modules/modulate_layers.py

@@ -0,0 +1,76 @@
+from typing import Callable
+
+import torch
+import torch.nn as nn
+
+
+class ModulateDiT(nn.Module):
+    """Modulation layer for DiT."""
+    def __init__(
+        self,
+        hidden_size: int,
+        factor: int,
+        act_layer: Callable,
+        dtype=None,
+        device=None,
+    ):
+        factory_kwargs = {"dtype": dtype, "device": device}
+        super().__init__()
+        self.act = act_layer()
+        self.linear = nn.Linear(
+            hidden_size, factor * hidden_size, bias=True, **factory_kwargs
+        )
+        # Zero-initialize the modulation
+        nn.init.zeros_(self.linear.weight)
+        nn.init.zeros_(self.linear.bias)
+
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        return self.linear(self.act(x))
+
+
+def modulate(x, shift=None, scale=None):
+    """modulate by shift and scale
+
+    Args:
+        x (torch.Tensor): input tensor.
+        shift (torch.Tensor, optional): shift tensor. Defaults to None.
+        scale (torch.Tensor, optional): scale tensor. Defaults to None.
+
+    Returns:
+        torch.Tensor: the output tensor after modulate.
+    """
+    if scale is None and shift is None:
+        return x
+    elif shift is None:
+        return x * (1 + scale.unsqueeze(1))
+    elif scale is None:
+        return x + shift.unsqueeze(1)
+    else:
+        return x * (1 + scale.unsqueeze(1)) + shift.unsqueeze(1)
+
+
+def apply_gate(x, gate=None, tanh=False):
+    """AI is creating summary for apply_gate
+
+    Args:
+        x (torch.Tensor): input tensor.
+        gate (torch.Tensor, optional): gate tensor. Defaults to None.
+        tanh (bool, optional): whether to use tanh function. Defaults to False.
+
+    Returns:
+        torch.Tensor: the output tensor after apply gate.
+    """
+    if gate is None:
+        return x
+    if tanh:
+        return x * gate.unsqueeze(1).tanh()
+    else:
+        return x * gate.unsqueeze(1)
+
+
+def ckpt_wrapper(module):
+    def ckpt_forward(*inputs):
+        outputs = module(*inputs)
+        return outputs
+
+    return ckpt_forward

hyvideo/modules/norm_layers.py

@@ -0,0 +1,77 @@
+import torch
+import torch.nn as nn
+
+
+class RMSNorm(nn.Module):
+    def __init__(
+        self,
+        dim: int,
+        elementwise_affine=True,
+        eps: float = 1e-6,
+        device=None,
+        dtype=None,
+    ):
+        """
+        Initialize the RMSNorm normalization layer.
+
+        Args:
+            dim (int): The dimension of the input tensor.
+            eps (float, optional): A small value added to the denominator for numerical stability. Default is 1e-6.
+
+        Attributes:
+            eps (float): A small value added to the denominator for numerical stability.
+            weight (nn.Parameter): Learnable scaling parameter.
+
+        """
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+        self.eps = eps
+        if elementwise_affine:
+            self.weight = nn.Parameter(torch.ones(dim, **factory_kwargs))
+
+    def _norm(self, x):
+        """
+        Apply the RMSNorm normalization to the input tensor.
+
+        Args:
+            x (torch.Tensor): The input tensor.
+
+        Returns:
+            torch.Tensor: The normalized tensor.
+
+        """
+        return x * torch.rsqrt(x.pow(2).mean(-1, keepdim=True) + self.eps)
+
+    def forward(self, x):
+        """
+        Forward pass through the RMSNorm layer.
+
+        Args:
+            x (torch.Tensor): The input tensor.
+
+        Returns:
+            torch.Tensor: The output tensor after applying RMSNorm.
+
+        """
+        output = self._norm(x.float()).type_as(x)
+        if hasattr(self, "weight"):
+            output = output * self.weight
+        return output
+
+
+def get_norm_layer(norm_layer):
+    """
+    Get the normalization layer.
+
+    Args:
+        norm_layer (str): The type of normalization layer.
+
+    Returns:
+        norm_layer (nn.Module): The normalization layer.
+    """
+    if norm_layer == "layer":
+        return nn.LayerNorm
+    elif norm_layer == "rms":
+        return RMSNorm
+    else:
+        raise NotImplementedError(f"Norm layer {norm_layer} is not implemented")

hyvideo/modules/posemb_layers.py

@@ -0,0 +1,310 @@
+import torch
+from typing import Union, Tuple, List
+
+
+def _to_tuple(x, dim=2):
+    if isinstance(x, int):
+        return (x,) * dim
+    elif len(x) == dim:
+        return x
+    else:
+        raise ValueError(f"Expected length {dim} or int, but got {x}")
+
+
+def get_meshgrid_nd(start, *args, dim=2):
+    """
+    Get n-D meshgrid with start, stop and num.
+
+    Args:
+        start (int or tuple): If len(args) == 0, start is num; If len(args) == 1, start is start, args[0] is stop,
+            step is 1; If len(args) == 2, start is start, args[0] is stop, args[1] is num. For n-dim, start/stop/num
+            should be int or n-tuple. If n-tuple is provided, the meshgrid will be stacked following the dim order in
+            n-tuples.
+        *args: See above.
+        dim (int): Dimension of the meshgrid. Defaults to 2.
+
+    Returns:
+        grid (np.ndarray): [dim, ...]
+    """
+    if len(args) == 0:
+        # start is grid_size
+        num = _to_tuple(start, dim=dim)
+        start = (0,) * dim
+        stop = num
+    elif len(args) == 1:
+        # start is start, args[0] is stop, step is 1
+        start = _to_tuple(start, dim=dim)
+        stop = _to_tuple(args[0], dim=dim)
+        num = [stop[i] - start[i] for i in range(dim)]
+    elif len(args) == 2:
+        # start is start, args[0] is stop, args[1] is num
+        start = _to_tuple(start, dim=dim)  # Left-Top       eg: 12,0
+        stop = _to_tuple(args[0], dim=dim)  # Right-Bottom   eg: 20,32
+        num = _to_tuple(args[1], dim=dim)  # Target Size    eg: 32,124
+    else:
+        raise ValueError(f"len(args) should be 0, 1 or 2, but got {len(args)}")
+
+    # PyTorch implement of np.linspace(start[i], stop[i], num[i], endpoint=False)
+    axis_grid = []
+    for i in range(dim):
+        a, b, n = start[i], stop[i], num[i]
+        g = torch.linspace(a, b, n + 1, dtype=torch.float32)[:n]
+        axis_grid.append(g)
+    grid = torch.meshgrid(*axis_grid, indexing="ij")  # dim x [W, H, D]
+    grid = torch.stack(grid, dim=0)  # [dim, W, H, D]
+
+    return grid
+
+
+#################################################################################
+#                   Rotary Positional Embedding Functions                       #
+#################################################################################
+# https://github.com/meta-llama/llama/blob/be327c427cc5e89cc1d3ab3d3fec4484df771245/llama/model.py#L80
+
+
+def reshape_for_broadcast(
+    freqs_cis: Union[torch.Tensor, Tuple[torch.Tensor]],
+    x: torch.Tensor,
+    head_first=False,
+):
+    """
+    Reshape frequency tensor for broadcasting it with another tensor.
+
+    This function reshapes the frequency tensor to have the same shape as the target tensor 'x'
+    for the purpose of broadcasting the frequency tensor during element-wise operations.
+
+    Notes:
+        When using FlashMHAModified, head_first should be False.
+        When using Attention, head_first should be True.
+
+    Args:
+        freqs_cis (Union[torch.Tensor, Tuple[torch.Tensor]]): Frequency tensor to be reshaped.
+        x (torch.Tensor): Target tensor for broadcasting compatibility.
+        head_first (bool): head dimension first (except batch dim) or not.
+
+    Returns:
+        torch.Tensor: Reshaped frequency tensor.
+
+    Raises:
+        AssertionError: If the frequency tensor doesn't match the expected shape.
+        AssertionError: If the target tensor 'x' doesn't have the expected number of dimensions.
+    """
+    ndim = x.ndim
+    assert 0 <= 1 < ndim
+
+    if isinstance(freqs_cis, tuple):
+        # freqs_cis: (cos, sin) in real space
+        if head_first:
+            assert freqs_cis[0].shape == (
+                x.shape[-2],
+                x.shape[-1],
+            ), f"freqs_cis shape {freqs_cis[0].shape} does not match x shape {x.shape}"
+            shape = [
+                d if i == ndim - 2 or i == ndim - 1 else 1
+                for i, d in enumerate(x.shape)
+            ]
+        else:
+            assert freqs_cis[0].shape == (
+                x.shape[1],
+                x.shape[-1],
+            ), f"freqs_cis shape {freqs_cis[0].shape} does not match x shape {x.shape}"
+            shape = [d if i == 1 or i == ndim - 1 else 1 for i, d in enumerate(x.shape)]
+        return freqs_cis[0].view(*shape), freqs_cis[1].view(*shape)
+    else:
+        # freqs_cis: values in complex space
+        if head_first:
+            assert freqs_cis.shape == (
+                x.shape[-2],
+                x.shape[-1],
+            ), f"freqs_cis shape {freqs_cis.shape} does not match x shape {x.shape}"
+            shape = [
+                d if i == ndim - 2 or i == ndim - 1 else 1
+                for i, d in enumerate(x.shape)
+            ]
+        else:
+            assert freqs_cis.shape == (
+                x.shape[1],
+                x.shape[-1],
+            ), f"freqs_cis shape {freqs_cis.shape} does not match x shape {x.shape}"
+            shape = [d if i == 1 or i == ndim - 1 else 1 for i, d in enumerate(x.shape)]
+        return freqs_cis.view(*shape)
+
+
+def rotate_half(x):
+    x_real, x_imag = (
+        x.float().reshape(*x.shape[:-1], -1, 2).unbind(-1)
+    )  # [B, S, H, D//2]
+    return torch.stack([-x_imag, x_real], dim=-1).flatten(3)
+
+
+def apply_rotary_emb(
+    xq: torch.Tensor,
+    xk: torch.Tensor,
+    freqs_cis: Union[torch.Tensor, Tuple[torch.Tensor, torch.Tensor]],
+    head_first: bool = False,
+) -> Tuple[torch.Tensor, torch.Tensor]:
+    """
+    Apply rotary embeddings to input tensors using the given frequency tensor.
+
+    This function applies rotary embeddings to the given query 'xq' and key 'xk' tensors using the provided
+    frequency tensor 'freqs_cis'. The input tensors are reshaped as complex numbers, and the frequency tensor
+    is reshaped for broadcasting compatibility. The resulting tensors contain rotary embeddings and are
+    returned as real tensors.
+
+    Args:
+        xq (torch.Tensor): Query tensor to apply rotary embeddings. [B, S, H, D]
+        xk (torch.Tensor): Key tensor to apply rotary embeddings.   [B, S, H, D]
+        freqs_cis (torch.Tensor or tuple): Precomputed frequency tensor for complex exponential.
+        head_first (bool): head dimension first (except batch dim) or not.
+
+    Returns:
+        Tuple[torch.Tensor, torch.Tensor]: Tuple of modified query tensor and key tensor with rotary embeddings.
+
+    """
+    xk_out = None
+    if isinstance(freqs_cis, tuple):
+        cos, sin = reshape_for_broadcast(freqs_cis, xq, head_first)  # [S, D]
+        cos, sin = cos.to(xq.device), sin.to(xq.device)
+        # real * cos - imag * sin
+        # imag * cos + real * sin
+        xq_out = (xq.float() * cos + rotate_half(xq.float()) * sin).type_as(xq)
+        xk_out = (xk.float() * cos + rotate_half(xk.float()) * sin).type_as(xk)
+    else:
+        # view_as_complex will pack [..., D/2, 2](real) to [..., D/2](complex)
+        xq_ = torch.view_as_complex(
+            xq.float().reshape(*xq.shape[:-1], -1, 2)
+        )  # [B, S, H, D//2]
+        freqs_cis = reshape_for_broadcast(freqs_cis, xq_, head_first).to(
+            xq.device
+        )  # [S, D//2] --> [1, S, 1, D//2]
+        # (real, imag) * (cos, sin) = (real * cos - imag * sin, imag * cos + real * sin)
+        # view_as_real will expand [..., D/2](complex) to [..., D/2, 2](real)
+        xq_out = torch.view_as_real(xq_ * freqs_cis).flatten(3).type_as(xq)
+        xk_ = torch.view_as_complex(
+            xk.float().reshape(*xk.shape[:-1], -1, 2)
+        )  # [B, S, H, D//2]
+        xk_out = torch.view_as_real(xk_ * freqs_cis).flatten(3).type_as(xk)
+
+    return xq_out, xk_out
+
+
+def get_nd_rotary_pos_embed(
+    rope_dim_list,
+    start,
+    *args,
+    theta=10000.0,
+    use_real=False,
+    theta_rescale_factor: Union[float, List[float]] = 1.0,
+    interpolation_factor: Union[float, List[float]] = 1.0,
+):
+    """
+    This is a n-d version of precompute_freqs_cis, which is a RoPE for tokens with n-d structure.
+
+    Args:
+        rope_dim_list (list of int): Dimension of each rope. len(rope_dim_list) should equal to n.
+            sum(rope_dim_list) should equal to head_dim of attention layer.
+        start (int | tuple of int | list of int): If len(args) == 0, start is num; If len(args) == 1, start is start,
+            args[0] is stop, step is 1; If len(args) == 2, start is start, args[0] is stop, args[1] is num.
+        *args: See above.
+        theta (float): Scaling factor for frequency computation. Defaults to 10000.0.
+        use_real (bool): If True, return real part and imaginary part separately. Otherwise, return complex numbers.
+            Some libraries such as TensorRT does not support complex64 data type. So it is useful to provide a real
+            part and an imaginary part separately.
+        theta_rescale_factor (float): Rescale factor for theta. Defaults to 1.0.
+
+    Returns:
+        pos_embed (torch.Tensor): [HW, D/2]
+    """
+
+    grid = get_meshgrid_nd(
+        start, *args, dim=len(rope_dim_list)
+    )  # [3, W, H, D] / [2, W, H]
+
+    if isinstance(theta_rescale_factor, int) or isinstance(theta_rescale_factor, float):
+        theta_rescale_factor = [theta_rescale_factor] * len(rope_dim_list)
+    elif isinstance(theta_rescale_factor, list) and len(theta_rescale_factor) == 1:
+        theta_rescale_factor = [theta_rescale_factor[0]] * len(rope_dim_list)
+    assert len(theta_rescale_factor) == len(
+        rope_dim_list
+    ), "len(theta_rescale_factor) should equal to len(rope_dim_list)"
+
+    if isinstance(interpolation_factor, int) or isinstance(interpolation_factor, float):
+        interpolation_factor = [interpolation_factor] * len(rope_dim_list)
+    elif isinstance(interpolation_factor, list) and len(interpolation_factor) == 1:
+        interpolation_factor = [interpolation_factor[0]] * len(rope_dim_list)
+    assert len(interpolation_factor) == len(
+        rope_dim_list
+    ), "len(interpolation_factor) should equal to len(rope_dim_list)"
+
+    # use 1/ndim of dimensions to encode grid_axis
+    embs = []
+    for i in range(len(rope_dim_list)):
+        emb = get_1d_rotary_pos_embed(
+            rope_dim_list[i],
+            grid[i].reshape(-1),
+            theta,
+            use_real=use_real,
+            theta_rescale_factor=theta_rescale_factor[i],
+            interpolation_factor=interpolation_factor[i],
+        )  # 2 x [WHD, rope_dim_list[i]]
+        embs.append(emb)
+
+    if use_real:
+        cos = torch.cat([emb[0] for emb in embs], dim=1)  # (WHD, D/2)
+        sin = torch.cat([emb[1] for emb in embs], dim=1)  # (WHD, D/2)
+        return cos, sin
+    else:
+        emb = torch.cat(embs, dim=1)  # (WHD, D/2)
+        return emb
+
+
+def get_1d_rotary_pos_embed(
+    dim: int,
+    pos: Union[torch.FloatTensor, int],
+    theta: float = 10000.0,
+    use_real: bool = False,
+    theta_rescale_factor: float = 1.0,
+    interpolation_factor: float = 1.0,
+) -> Union[torch.Tensor, Tuple[torch.Tensor, torch.Tensor]]:
+    """
+    Precompute the frequency tensor for complex exponential (cis) with given dimensions.
+    (Note: `cis` means `cos + i * sin`, where i is the imaginary unit.)
+
+    This function calculates a frequency tensor with complex exponential using the given dimension 'dim'
+    and the end index 'end'. The 'theta' parameter scales the frequencies.
+    The returned tensor contains complex values in complex64 data type.
+
+    Args:
+        dim (int): Dimension of the frequency tensor.
+        pos (int or torch.FloatTensor): Position indices for the frequency tensor. [S] or scalar
+        theta (float, optional): Scaling factor for frequency computation. Defaults to 10000.0.
+        use_real (bool, optional): If True, return real part and imaginary part separately.
+                                   Otherwise, return complex numbers.
+        theta_rescale_factor (float, optional): Rescale factor for theta. Defaults to 1.0.
+
+    Returns:
+        freqs_cis: Precomputed frequency tensor with complex exponential. [S, D/2]
+        freqs_cos, freqs_sin: Precomputed frequency tensor with real and imaginary parts separately. [S, D]
+    """
+    if isinstance(pos, int):
+        pos = torch.arange(pos).float()
+
+    # proposed by reddit user bloc97, to rescale rotary embeddings to longer sequence length without fine-tuning
+    # has some connection to NTK literature
+    if theta_rescale_factor != 1.0:
+        theta *= theta_rescale_factor ** (dim / (dim - 2))
+
+    freqs = 1.0 / (
+        theta ** (torch.arange(0, dim, 2)[: (dim // 2)].float() / dim)
+    )  # [D/2]
+    # assert interpolation_factor == 1.0, f"interpolation_factor: {interpolation_factor}"
+    freqs = torch.outer(pos * interpolation_factor, freqs)  # [S, D/2]
+    if use_real:
+        freqs_cos = freqs.cos().repeat_interleave(2, dim=1)  # [S, D]
+        freqs_sin = freqs.sin().repeat_interleave(2, dim=1)  # [S, D]
+        return freqs_cos, freqs_sin
+    else:
+        freqs_cis = torch.polar(
+            torch.ones_like(freqs), freqs
+        )  # complex64     # [S, D/2]
+        return freqs_cis

hyvideo/modules/token_refiner.py

@@ -0,0 +1,236 @@
+from typing import Optional
+
+from einops import rearrange
+import torch
+import torch.nn as nn
+
+from .activation_layers import get_activation_layer
+from .attenion import attention
+from .norm_layers import get_norm_layer
+from .embed_layers import TimestepEmbedder, TextProjection
+from .attenion import attention
+from .mlp_layers import MLP
+from .modulate_layers import modulate, apply_gate
+
+
+class IndividualTokenRefinerBlock(nn.Module):
+    def __init__(
+        self,
+        hidden_size,
+        heads_num,
+        mlp_width_ratio: str = 4.0,
+        mlp_drop_rate: float = 0.0,
+        act_type: str = "silu",
+        qk_norm: bool = False,
+        qk_norm_type: str = "layer",
+        qkv_bias: bool = True,
+        dtype: Optional[torch.dtype] = None,
+        device: Optional[torch.device] = None,
+    ):
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+        self.heads_num = heads_num
+        head_dim = hidden_size // heads_num
+        mlp_hidden_dim = int(hidden_size * mlp_width_ratio)
+
+        self.norm1 = nn.LayerNorm(
+            hidden_size, elementwise_affine=True, eps=1e-6, **factory_kwargs
+        )
+        self.self_attn_qkv = nn.Linear(
+            hidden_size, hidden_size * 3, bias=qkv_bias, **factory_kwargs
+        )
+        qk_norm_layer = get_norm_layer(qk_norm_type)
+        self.self_attn_q_norm = (
+            qk_norm_layer(head_dim, elementwise_affine=True, eps=1e-6, **factory_kwargs)
+            if qk_norm
+            else nn.Identity()
+        )
+        self.self_attn_k_norm = (
+            qk_norm_layer(head_dim, elementwise_affine=True, eps=1e-6, **factory_kwargs)
+            if qk_norm
+            else nn.Identity()
+        )
+        self.self_attn_proj = nn.Linear(
+            hidden_size, hidden_size, bias=qkv_bias, **factory_kwargs
+        )
+
+        self.norm2 = nn.LayerNorm(
+            hidden_size, elementwise_affine=True, eps=1e-6, **factory_kwargs
+        )
+        act_layer = get_activation_layer(act_type)
+        self.mlp = MLP(
+            in_channels=hidden_size,
+            hidden_channels=mlp_hidden_dim,
+            act_layer=act_layer,
+            drop=mlp_drop_rate,
+            **factory_kwargs,
+        )
+
+        self.adaLN_modulation = nn.Sequential(
+            act_layer(),
+            nn.Linear(hidden_size, 2 * hidden_size, bias=True, **factory_kwargs),
+        )
+        # Zero-initialize the modulation
+        nn.init.zeros_(self.adaLN_modulation[1].weight)
+        nn.init.zeros_(self.adaLN_modulation[1].bias)
+
+    def forward(
+        self,
+        x: torch.Tensor,
+        c: torch.Tensor,  # timestep_aware_representations + context_aware_representations
+        attn_mask: torch.Tensor = None,
+    ):
+        gate_msa, gate_mlp = self.adaLN_modulation(c).chunk(2, dim=1)
+
+        norm_x = self.norm1(x)
+        qkv = self.self_attn_qkv(norm_x)
+        q, k, v = rearrange(qkv, "B L (K H D) -> K B L H D", K=3, H=self.heads_num)
+        # Apply QK-Norm if needed
+        q = self.self_attn_q_norm(q).to(v)
+        k = self.self_attn_k_norm(k).to(v)
+
+        # Self-Attention
+        attn = attention(q, k, v, mode="torch", attn_mask=attn_mask)
+
+        x = x + apply_gate(self.self_attn_proj(attn), gate_msa)
+
+        # FFN Layer
+        x = x + apply_gate(self.mlp(self.norm2(x)), gate_mlp)
+
+        return x
+
+
+class IndividualTokenRefiner(nn.Module):
+    def __init__(
+        self,
+        hidden_size,
+        heads_num,
+        depth,
+        mlp_width_ratio: float = 4.0,
+        mlp_drop_rate: float = 0.0,
+        act_type: str = "silu",
+        qk_norm: bool = False,
+        qk_norm_type: str = "layer",
+        qkv_bias: bool = True,
+        dtype: Optional[torch.dtype] = None,
+        device: Optional[torch.device] = None,
+    ):
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+        self.blocks = nn.ModuleList(
+            [
+                IndividualTokenRefinerBlock(
+                    hidden_size=hidden_size,
+                    heads_num=heads_num,
+                    mlp_width_ratio=mlp_width_ratio,
+                    mlp_drop_rate=mlp_drop_rate,
+                    act_type=act_type,
+                    qk_norm=qk_norm,
+                    qk_norm_type=qk_norm_type,
+                    qkv_bias=qkv_bias,
+                    **factory_kwargs,
+                )
+                for _ in range(depth)
+            ]
+        )
+
+    def forward(
+        self,
+        x: torch.Tensor,
+        c: torch.LongTensor,
+        mask: Optional[torch.Tensor] = None,
+    ):
+        self_attn_mask = None
+        if mask is not None:
+            batch_size = mask.shape[0]
+            seq_len = mask.shape[1]
+            mask = mask.to(x.device)
+            # batch_size x 1 x seq_len x seq_len
+            self_attn_mask_1 = mask.view(batch_size, 1, 1, seq_len).repeat(
+                1, 1, seq_len, 1
+            )
+            # batch_size x 1 x seq_len x seq_len
+            self_attn_mask_2 = self_attn_mask_1.transpose(2, 3)
+            # batch_size x 1 x seq_len x seq_len, 1 for broadcasting of heads_num
+            self_attn_mask = (self_attn_mask_1 & self_attn_mask_2).bool()
+            # avoids self-attention weight being NaN for padding tokens
+            self_attn_mask[:, :, :, 0] = True
+
+        for block in self.blocks:
+            x = block(x, c, self_attn_mask)
+        return x
+
+
+class SingleTokenRefiner(nn.Module):
+    """
+    A single token refiner block for llm text embedding refine.
+    """
+    def __init__(
+        self,
+        in_channels,
+        hidden_size,
+        heads_num,
+        depth,
+        mlp_width_ratio: float = 4.0,
+        mlp_drop_rate: float = 0.0,
+        act_type: str = "silu",
+        qk_norm: bool = False,
+        qk_norm_type: str = "layer",
+        qkv_bias: bool = True,
+        attn_mode: str = "torch",
+        dtype: Optional[torch.dtype] = None,
+        device: Optional[torch.device] = None,
+    ):
+        factory_kwargs = {"device": device, "dtype": dtype}
+        super().__init__()
+        self.attn_mode = attn_mode
+        assert self.attn_mode == "torch", "Only support 'torch' mode for token refiner."
+
+        self.input_embedder = nn.Linear(
+            in_channels, hidden_size, bias=True, **factory_kwargs
+        )
+
+        act_layer = get_activation_layer(act_type)
+        # Build timestep embedding layer
+        self.t_embedder = TimestepEmbedder(hidden_size, act_layer, **factory_kwargs)
+        # Build context embedding layer
+        self.c_embedder = TextProjection(
+            in_channels, hidden_size, act_layer, **factory_kwargs
+        )
+
+        self.individual_token_refiner = IndividualTokenRefiner(
+            hidden_size=hidden_size,
+            heads_num=heads_num,
+            depth=depth,
+            mlp_width_ratio=mlp_width_ratio,
+            mlp_drop_rate=mlp_drop_rate,
+            act_type=act_type,
+            qk_norm=qk_norm,
+            qk_norm_type=qk_norm_type,
+            qkv_bias=qkv_bias,
+            **factory_kwargs,
+        )
+
+    def forward(
+        self,
+        x: torch.Tensor,
+        t: torch.LongTensor,
+        mask: Optional[torch.LongTensor] = None,
+    ):
+        timestep_aware_representations = self.t_embedder(t)
+
+        if mask is None:
+            context_aware_representations = x.mean(dim=1)
+        else:
+            mask_float = mask.float().unsqueeze(-1)  # [b, s1, 1]
+            context_aware_representations = (x * mask_float).sum(
+                dim=1
+            ) / mask_float.sum(dim=1)
+        context_aware_representations = self.c_embedder(context_aware_representations)
+        c = timestep_aware_representations + context_aware_representations
+
+        x = self.input_embedder(x)
+
+        x = self.individual_token_refiner(x, c, mask)
+
+        return x

hyvideo/prompt_rewrite.py

@@ -0,0 +1,51 @@
+normal_mode_prompt = """Normal mode - Video Recaption Task:
+
+You are a large language model specialized in rewriting video descriptions. Your task is to modify the input description.
+
+0. Preserve ALL information, including style words and technical terms.
+
+1. If the input is in Chinese, translate the entire description to English. 
+
+2. If the input is just one or two words describing an object or person, provide a brief, simple description focusing on basic visual characteristics. Limit the description to 1-2 short sentences.
+
+3. If the input does not include style, lighting, atmosphere, you can make reasonable associations.
+
+4. Output ALL must be in English.
+
+Given Input:
+input: "{input}"
+"""
+
+
+master_mode_prompt = """Master mode - Video Recaption Task:
+
+You are a large language model specialized in rewriting video descriptions. Your task is to modify the input description.
+
+0. Preserve ALL information, including style words and technical terms.
+
+1. If the input is in Chinese, translate the entire description to English. 
+
+2. If the input is just one or two words describing an object or person, provide a brief, simple description focusing on basic visual characteristics. Limit the description to 1-2 short sentences.
+
+3. If the input does not include style, lighting, atmosphere, you can make reasonable associations.
+
+4. Output ALL must be in English.
+
+Given Input:
+input: "{input}"
+"""
+
+def get_rewrite_prompt(ori_prompt, mode="Normal"):
+    if mode == "Normal":
+        prompt = normal_mode_prompt.format(input=ori_prompt)
+    elif mode == "Master":
+        prompt = master_mode_prompt.format(input=ori_prompt)
+    else:
+        raise Exception("Only supports Normal and Normal", mode)
+    return prompt
+
+ori_prompt = "一只小狗在草地上奔跑。"
+normal_prompt = get_rewrite_prompt(ori_prompt, mode="Normal")
+master_prompt = get_rewrite_prompt(ori_prompt, mode="Master")
+
+# Then you can use the normal_prompt or master_prompt to access the hunyuan-large rewrite model to get the final prompt.

hyvideo/text_encoder/__init__.py

@@ -0,0 +1,357 @@
+from dataclasses import dataclass
+from typing import Optional, Tuple
+from copy import deepcopy
+
+import torch
+import torch.nn as nn
+from transformers import CLIPTextModel, CLIPTokenizer, AutoTokenizer, AutoModel
+from transformers.utils import ModelOutput
+
+from ..constants import TEXT_ENCODER_PATH, TOKENIZER_PATH
+from ..constants import PRECISION_TO_TYPE
+
+
+def use_default(value, default):
+    return value if value is not None else default
+
+
+def load_text_encoder(
+    text_encoder_type,
+    text_encoder_precision=None,
+    text_encoder_path=None,
+    logger=None,
+    device=None,
+):
+    if text_encoder_path is None:
+        text_encoder_path = TEXT_ENCODER_PATH[text_encoder_type]
+    if logger is not None:
+        logger.info(
+            f"Loading text encoder model ({text_encoder_type}) from: {text_encoder_path}"
+        )
+
+    if text_encoder_type == "clipL":
+        text_encoder = CLIPTextModel.from_pretrained(text_encoder_path)
+        text_encoder.final_layer_norm = text_encoder.text_model.final_layer_norm
+    elif text_encoder_type == "llm":
+        text_encoder = AutoModel.from_pretrained(
+            text_encoder_path, low_cpu_mem_usage=True
+        )
+        text_encoder.final_layer_norm = text_encoder.norm
+    else:
+        raise ValueError(f"Unsupported text encoder type: {text_encoder_type}")
+    # from_pretrained will ensure that the model is in eval mode.
+
+    if text_encoder_precision is not None:
+        text_encoder = text_encoder.to(dtype=PRECISION_TO_TYPE[text_encoder_precision])
+
+    text_encoder.requires_grad_(False)
+
+    if logger is not None:
+        logger.info(f"Text encoder to dtype: {text_encoder.dtype}")
+
+    if device is not None:
+        text_encoder = text_encoder.to(device)
+
+    return text_encoder, text_encoder_path
+
+
+def load_tokenizer(
+    tokenizer_type, tokenizer_path=None, padding_side="right", logger=None
+):
+    if tokenizer_path is None:
+        tokenizer_path = TOKENIZER_PATH[tokenizer_type]
+    if logger is not None:
+        logger.info(f"Loading tokenizer ({tokenizer_type}) from: {tokenizer_path}")
+
+    if tokenizer_type == "clipL":
+        tokenizer = CLIPTokenizer.from_pretrained(tokenizer_path, max_length=77)
+    elif tokenizer_type == "llm":
+        tokenizer = AutoTokenizer.from_pretrained(
+            tokenizer_path, padding_side=padding_side
+        )
+    else:
+        raise ValueError(f"Unsupported tokenizer type: {tokenizer_type}")
+
+    return tokenizer, tokenizer_path
+
+
+@dataclass
+class TextEncoderModelOutput(ModelOutput):
+    """
+    Base class for model's outputs that also contains a pooling of the last hidden states.
+
+    Args:
+        hidden_state (`torch.FloatTensor` of shape `(batch_size, sequence_length, hidden_size)`):
+            Sequence of hidden-states at the output of the last layer of the model.
+        attention_mask (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
+            Mask to avoid performing attention on padding token indices. Mask values selected in ``[0, 1]``:
+        hidden_states_list (`tuple(torch.FloatTensor)`, *optional*, returned when `output_hidden_states=True` is passed):
+            Tuple of `torch.FloatTensor` (one for the output of the embeddings, if the model has an embedding layer, +
+            one for the output of each layer) of shape `(batch_size, sequence_length, hidden_size)`.
+            Hidden-states of the model at the output of each layer plus the optional initial embedding outputs.
+        text_outputs (`list`, *optional*, returned when `return_texts=True` is passed):
+            List of decoded texts.
+    """
+
+    hidden_state: torch.FloatTensor = None
+    attention_mask: Optional[torch.LongTensor] = None
+    hidden_states_list: Optional[Tuple[torch.FloatTensor, ...]] = None
+    text_outputs: Optional[list] = None
+
+
+class TextEncoder(nn.Module):
+    def __init__(
+        self,
+        text_encoder_type: str,
+        max_length: int,
+        text_encoder_precision: Optional[str] = None,
+        text_encoder_path: Optional[str] = None,
+        tokenizer_type: Optional[str] = None,
+        tokenizer_path: Optional[str] = None,
+        output_key: Optional[str] = None,
+        use_attention_mask: bool = True,
+        input_max_length: Optional[int] = None,
+        prompt_template: Optional[dict] = None,
+        prompt_template_video: Optional[dict] = None,
+        hidden_state_skip_layer: Optional[int] = None,
+        apply_final_norm: bool = False,
+        reproduce: bool = False,
+        logger=None,
+        device=None,
+    ):
+        super().__init__()
+        self.text_encoder_type = text_encoder_type
+        self.max_length = max_length
+        self.precision = text_encoder_precision
+        self.model_path = text_encoder_path
+        self.tokenizer_type = (
+            tokenizer_type if tokenizer_type is not None else text_encoder_type
+        )
+        self.tokenizer_path = (
+            tokenizer_path if tokenizer_path is not None else text_encoder_path
+        )
+        self.use_attention_mask = use_attention_mask
+        if prompt_template_video is not None:
+            assert (
+                use_attention_mask is True
+            ), "Attention mask is True required when training videos."
+        self.input_max_length = (
+            input_max_length if input_max_length is not None else max_length
+        )
+        self.prompt_template = prompt_template
+        self.prompt_template_video = prompt_template_video
+        self.hidden_state_skip_layer = hidden_state_skip_layer
+        self.apply_final_norm = apply_final_norm
+        self.reproduce = reproduce
+        self.logger = logger
+
+        self.use_template = self.prompt_template is not None
+        if self.use_template:
+            assert (
+                isinstance(self.prompt_template, dict)
+                and "template" in self.prompt_template
+            ), f"`prompt_template` must be a dictionary with a key 'template', got {self.prompt_template}"
+            assert "{}" in str(self.prompt_template["template"]), (
+                "`prompt_template['template']` must contain a placeholder `{}` for the input text, "
+                f"got {self.prompt_template['template']}"
+            )
+
+        self.use_video_template = self.prompt_template_video is not None
+        if self.use_video_template:
+            if self.prompt_template_video is not None:
+                assert (
+                    isinstance(self.prompt_template_video, dict)
+                    and "template" in self.prompt_template_video
+                ), f"`prompt_template_video` must be a dictionary with a key 'template', got {self.prompt_template_video}"
+            assert "{}" in str(self.prompt_template_video["template"]), (
+                "`prompt_template_video['template']` must contain a placeholder `{}` for the input text, "
+                f"got {self.prompt_template_video['template']}"
+            )
+
+        if "t5" in text_encoder_type:
+            self.output_key = output_key or "last_hidden_state"
+        elif "clip" in text_encoder_type:
+            self.output_key = output_key or "pooler_output"
+        elif "llm" in text_encoder_type or "glm" in text_encoder_type:
+            self.output_key = output_key or "last_hidden_state"
+        else:
+            raise ValueError(f"Unsupported text encoder type: {text_encoder_type}")
+
+        self.model, self.model_path = load_text_encoder(
+            text_encoder_type=self.text_encoder_type,
+            text_encoder_precision=self.precision,
+            text_encoder_path=self.model_path,
+            logger=self.logger,
+            device=device,
+        )
+        self.dtype = self.model.dtype
+        self.device = self.model.device
+
+        self.tokenizer, self.tokenizer_path = load_tokenizer(
+            tokenizer_type=self.tokenizer_type,
+            tokenizer_path=self.tokenizer_path,
+            padding_side="right",
+            logger=self.logger,
+        )
+
+    def __repr__(self):
+        return f"{self.text_encoder_type} ({self.precision} - {self.model_path})"
+
+    @staticmethod
+    def apply_text_to_template(text, template, prevent_empty_text=True):
+        """
+        Apply text to template.
+
+        Args:
+            text (str): Input text.
+            template (str or list): Template string or list of chat conversation.
+            prevent_empty_text (bool): If Ture, we will prevent the user text from being empty
+                by adding a space. Defaults to True.
+        """
+        if isinstance(template, str):
+            # Will send string to tokenizer. Used for llm
+            return template.format(text)
+        else:
+            raise TypeError(f"Unsupported template type: {type(template)}")
+
+    def text2tokens(self, text, data_type="image"):
+        """
+        Tokenize the input text.
+
+        Args:
+            text (str or list): Input text.
+        """
+        tokenize_input_type = "str"
+        if self.use_template:
+            if data_type == "image":
+                prompt_template = self.prompt_template["template"]
+            elif data_type == "video":
+                prompt_template = self.prompt_template_video["template"]
+            else:
+                raise ValueError(f"Unsupported data type: {data_type}")
+            if isinstance(text, (list, tuple)):
+                text = [
+                    self.apply_text_to_template(one_text, prompt_template)
+                    for one_text in text
+                ]
+                if isinstance(text[0], list):
+                    tokenize_input_type = "list"
+            elif isinstance(text, str):
+                text = self.apply_text_to_template(text, prompt_template)
+                if isinstance(text, list):
+                    tokenize_input_type = "list"
+            else:
+                raise TypeError(f"Unsupported text type: {type(text)}")
+
+        kwargs = dict(
+            truncation=True,
+            max_length=self.max_length,
+            padding="max_length",
+            return_tensors="pt",
+        )
+        if tokenize_input_type == "str":
+            return self.tokenizer(
+                text,
+                return_length=False,
+                return_overflowing_tokens=False,
+                return_attention_mask=True,
+                **kwargs,
+            )
+        elif tokenize_input_type == "list":
+            return self.tokenizer.apply_chat_template(
+                text,
+                add_generation_prompt=True,
+                tokenize=True,
+                return_dict=True,
+                **kwargs,
+            )
+        else:
+            raise ValueError(f"Unsupported tokenize_input_type: {tokenize_input_type}")
+
+    def encode(
+        self,
+        batch_encoding,
+        use_attention_mask=None,
+        output_hidden_states=False,
+        do_sample=None,
+        hidden_state_skip_layer=None,
+        return_texts=False,
+        data_type="image",
+        device=None,
+    ):
+        """
+        Args:
+            batch_encoding (dict): Batch encoding from tokenizer.
+            use_attention_mask (bool): Whether to use attention mask. If None, use self.use_attention_mask.
+                Defaults to None.
+            output_hidden_states (bool): Whether to output hidden states. If False, return the value of
+                self.output_key. If True, return the entire output. If set self.hidden_state_skip_layer,
+                output_hidden_states will be set True. Defaults to False.
+            do_sample (bool): Whether to sample from the model. Used for Decoder-Only LLMs. Defaults to None.
+                When self.produce is False, do_sample is set to True by default.
+            hidden_state_skip_layer (int): Number of hidden states to hidden_state_skip_layer. 0 means the last layer.
+                If None, self.output_key will be used. Defaults to None.
+            return_texts (bool): Whether to return the decoded texts. Defaults to False.
+        """
+        device = self.model.device if device is None else device
+        use_attention_mask = use_default(use_attention_mask, self.use_attention_mask)
+        hidden_state_skip_layer = use_default(
+            hidden_state_skip_layer, self.hidden_state_skip_layer
+        )
+        do_sample = use_default(do_sample, not self.reproduce)
+        attention_mask = (
+            batch_encoding["attention_mask"].to(device) if use_attention_mask else None
+        )
+        outputs = self.model(
+            input_ids=batch_encoding["input_ids"].to(device),
+            attention_mask=attention_mask,
+            output_hidden_states=output_hidden_states
+            or hidden_state_skip_layer is not None,
+        )
+        if hidden_state_skip_layer is not None:
+            last_hidden_state = outputs.hidden_states[-(hidden_state_skip_layer + 1)]
+            # Real last hidden state already has layer norm applied. So here we only apply it
+            # for intermediate layers.
+            if hidden_state_skip_layer > 0 and self.apply_final_norm:
+                last_hidden_state = self.model.final_layer_norm(last_hidden_state)
+        else:
+            last_hidden_state = outputs[self.output_key]
+
+        # Remove hidden states of instruction tokens, only keep prompt tokens.
+        if self.use_template:
+            if data_type == "image":
+                crop_start = self.prompt_template.get("crop_start", -1)
+            elif data_type == "video":
+                crop_start = self.prompt_template_video.get("crop_start", -1)
+            else:
+                raise ValueError(f"Unsupported data type: {data_type}")
+            if crop_start > 0:
+                last_hidden_state = last_hidden_state[:, crop_start:]
+                attention_mask = (
+                    attention_mask[:, crop_start:] if use_attention_mask else None
+                )
+
+        if output_hidden_states:
+            return TextEncoderModelOutput(
+                last_hidden_state, attention_mask, outputs.hidden_states
+            )
+        return TextEncoderModelOutput(last_hidden_state, attention_mask)
+
+    def forward(
+        self,
+        text,
+        use_attention_mask=None,
+        output_hidden_states=False,
+        do_sample=False,
+        hidden_state_skip_layer=None,
+        return_texts=False,
+    ):
+        batch_encoding = self.text2tokens(text)
+        return self.encode(
+            batch_encoding,
+            use_attention_mask=use_attention_mask,
+            output_hidden_states=output_hidden_states,
+            do_sample=do_sample,
+            hidden_state_skip_layer=hidden_state_skip_layer,
+            return_texts=return_texts,
+        )

hyvideo/utils/data_utils.py

@@ -0,0 +1,15 @@
+import numpy as np
+import math
+
+
+def align_to(value, alignment):
+    """align hight, width according to alignment
+
+    Args:
+        value (int): height or width
+        alignment (int): target alignment factor
+
+    Returns:
+        int: the aligned value
+    """
+    return int(math.ceil(value / alignment) * alignment)

hyvideo/utils/file_utils.py

@@ -0,0 +1,70 @@
+import os
+from pathlib import Path
+from einops import rearrange
+
+import torch
+import torchvision
+import numpy as np
+import imageio
+
+CODE_SUFFIXES = {
+    ".py",  # Python codes
+    ".sh",  # Shell scripts
+    ".yaml",
+    ".yml",  # Configuration files
+}
+
+
+def safe_dir(path):
+    """
+    Create a directory (or the parent directory of a file) if it does not exist.
+
+    Args:
+        path (str or Path): Path to the directory.
+
+    Returns:
+        path (Path): Path object of the directory.
+    """
+    path = Path(path)
+    path.mkdir(exist_ok=True, parents=True)
+    return path
+
+
+def safe_file(path):
+    """
+    Create the parent directory of a file if it does not exist.
+
+    Args:
+        path (str or Path): Path to the file.
+
+    Returns:
+        path (Path): Path object of the file.
+    """
+    path = Path(path)
+    path.parent.mkdir(exist_ok=True, parents=True)
+    return path
+
+def save_videos_grid(videos: torch.Tensor, path: str, rescale=False, n_rows=1, fps=24):
+    """save videos by video tensor
+       copy from https://github.com/guoyww/AnimateDiff/blob/e92bd5671ba62c0d774a32951453e328018b7c5b/animatediff/utils/util.py#L61
+
+    Args:
+        videos (torch.Tensor): video tensor predicted by the model
+        path (str): path to save video
+        rescale (bool, optional): rescale the video tensor from [-1, 1] to  . Defaults to False.
+        n_rows (int, optional): Defaults to 1.
+        fps (int, optional): video save fps. Defaults to 8.
+    """
+    videos = rearrange(videos, "b c t h w -> t b c h w")
+    outputs = []
+    for x in videos:
+        x = torchvision.utils.make_grid(x, nrow=n_rows)
+        x = x.transpose(0, 1).transpose(1, 2).squeeze(-1)
+        if rescale:
+            x = (x + 1.0) / 2.0  # -1,1 -> 0,1
+        x = torch.clamp(x, 0, 1)
+        x = (x * 255).numpy().astype(np.uint8)
+        outputs.append(x)
+
+    os.makedirs(os.path.dirname(path), exist_ok=True)
+    imageio.mimsave(path, outputs, fps=fps)

hyvideo/utils/helpers.py

@@ -0,0 +1,40 @@
+import collections.abc
+
+from itertools import repeat
+
+
+def _ntuple(n):
+    def parse(x):
+        if isinstance(x, collections.abc.Iterable) and not isinstance(x, str):
+            x = tuple(x)
+            if len(x) == 1:
+                x = tuple(repeat(x[0], n))
+            return x
+        return tuple(repeat(x, n))
+    return parse
+
+
+to_1tuple = _ntuple(1)
+to_2tuple = _ntuple(2)
+to_3tuple = _ntuple(3)
+to_4tuple = _ntuple(4)
+
+
+def as_tuple(x):
+    if isinstance(x, collections.abc.Iterable) and not isinstance(x, str):
+        return tuple(x)
+    if x is None or isinstance(x, (int, float, str)):
+        return (x,)
+    else:
+        raise ValueError(f"Unknown type {type(x)}")
+
+
+def as_list_of_2tuple(x):
+    x = as_tuple(x)
+    if len(x) == 1:
+        x = (x[0], x[0])
+    assert len(x) % 2 == 0, f"Expect even length, got {len(x)}."
+    lst = []
+    for i in range(0, len(x), 2):
+        lst.append((x[i], x[i + 1]))
+    return lst

hyvideo/utils/preprocess_text_encoder_tokenizer_utils.py

@@ -0,0 +1,46 @@
+import argparse
+import torch
+from transformers import (
+    AutoProcessor,
+    LlavaForConditionalGeneration,
+)
+
+
+def preprocess_text_encoder_tokenizer(args):
+
+    processor = AutoProcessor.from_pretrained(args.input_dir)
+    model = LlavaForConditionalGeneration.from_pretrained(
+        args.input_dir,
+        torch_dtype=torch.float16,
+        low_cpu_mem_usage=True,
+    ).to(0)
+
+    model.language_model.save_pretrained(
+        f"{args.output_dir}"
+    )
+    processor.tokenizer.save_pretrained(
+        f"{args.output_dir}"
+    )
+
+if __name__ == "__main__":
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--input_dir",
+        type=str,
+        required=True,
+        help="The path to the llava-llama-3-8b-v1_1-transformers.",
+    )
+    parser.add_argument(
+        "--output_dir",
+        type=str,
+        default="",
+        help="The output path of the llava-llama-3-8b-text-encoder-tokenizer."
+        "if '', the parent dir of output will be the same as input dir.",
+    )
+    args = parser.parse_args()
+
+    if len(args.output_dir) == 0:
+        args.output_dir = "/".join(args.input_dir.split("/")[:-1])
+
+    preprocess_text_encoder_tokenizer(args)

hyvideo/vae/__init__.py

@@ -0,0 +1,62 @@
+from pathlib import Path
+
+import torch
+
+from .autoencoder_kl_causal_3d import AutoencoderKLCausal3D
+from ..constants import VAE_PATH, PRECISION_TO_TYPE
+
+def load_vae(vae_type: str="884-16c-hy",
+             vae_precision: str=None,
+             sample_size: tuple=None,
+             vae_path: str=None,
+             logger=None,
+             device=None
+             ):
+    """the fucntion to load the 3D VAE model
+
+    Args:
+        vae_type (str): the type of the 3D VAE model. Defaults to "884-16c-hy".
+        vae_precision (str, optional): the precision to load vae. Defaults to None.
+        sample_size (tuple, optional): the tiling size. Defaults to None.
+        vae_path (str, optional): the path to vae. Defaults to None.
+        logger (_type_, optional): logger. Defaults to None.
+        device (_type_, optional): device to load vae. Defaults to None.
+    """
+    if vae_path is None:
+        vae_path = VAE_PATH[vae_type]
+    
+    if logger is not None:
+        logger.info(f"Loading 3D VAE model ({vae_type}) from: {vae_path}")
+    config = AutoencoderKLCausal3D.load_config(vae_path)
+    if sample_size:
+        vae = AutoencoderKLCausal3D.from_config(config, sample_size=sample_size)
+    else:
+        vae = AutoencoderKLCausal3D.from_config(config)
+    
+    vae_ckpt = Path(vae_path) / "pytorch_model.pt"
+    assert vae_ckpt.exists(), f"VAE checkpoint not found: {vae_ckpt}"
+    
+    ckpt = torch.load(vae_ckpt, map_location=vae.device)
+    if "state_dict" in ckpt:
+        ckpt = ckpt["state_dict"]
+    if any(k.startswith("vae.") for k in ckpt.keys()):
+        ckpt = {k.replace("vae.", ""): v for k, v in ckpt.items() if k.startswith("vae.")}
+    vae.load_state_dict(ckpt)
+
+    spatial_compression_ratio = vae.config.spatial_compression_ratio
+    time_compression_ratio = vae.config.time_compression_ratio
+    
+    if vae_precision is not None:
+        vae = vae.to(dtype=PRECISION_TO_TYPE[vae_precision])
+
+    vae.requires_grad_(False)
+
+    if logger is not None:
+        logger.info(f"VAE to dtype: {vae.dtype}")
+
+    if device is not None:
+        vae = vae.to(device)
+
+    vae.eval()
+
+    return vae, vae_path, spatial_compression_ratio, time_compression_ratio

hyvideo/vae/autoencoder_kl_causal_3d.py

@@ -0,0 +1,603 @@
+# Copyright 2024 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+#
+# Modified from diffusers==0.29.2
+#
+# ==============================================================================
+from typing import Dict, Optional, Tuple, Union
+from dataclasses import dataclass
+
+import torch
+import torch.nn as nn
+
+from diffusers.configuration_utils import ConfigMixin, register_to_config
+
+try:
+    # This diffusers is modified and packed in the mirror.
+    from diffusers.loaders import FromOriginalVAEMixin
+except ImportError:
+    # Use this to be compatible with the original diffusers.
+    from diffusers.loaders.single_file_model import FromOriginalModelMixin as FromOriginalVAEMixin
+from diffusers.utils.accelerate_utils import apply_forward_hook
+from diffusers.models.attention_processor import (
+    ADDED_KV_ATTENTION_PROCESSORS,
+    CROSS_ATTENTION_PROCESSORS,
+    Attention,
+    AttentionProcessor,
+    AttnAddedKVProcessor,
+    AttnProcessor,
+)
+from diffusers.models.modeling_outputs import AutoencoderKLOutput
+from diffusers.models.modeling_utils import ModelMixin
+from .vae import DecoderCausal3D, BaseOutput, DecoderOutput, DiagonalGaussianDistribution, EncoderCausal3D
+
+
+@dataclass
+class DecoderOutput2(BaseOutput):
+    sample: torch.FloatTensor
+    posterior: Optional[DiagonalGaussianDistribution] = None
+
+
+class AutoencoderKLCausal3D(ModelMixin, ConfigMixin, FromOriginalVAEMixin):
+    r"""
+    A VAE model with KL loss for encoding images/videos into latents and decoding latent representations into images/videos.
+
+    This model inherits from [`ModelMixin`]. Check the superclass documentation for it's generic methods implemented
+    for all models (such as downloading or saving).
+    """
+
+    _supports_gradient_checkpointing = True
+
+    @register_to_config
+    def __init__(
+        self,
+        in_channels: int = 3,
+        out_channels: int = 3,
+        down_block_types: Tuple[str] = ("DownEncoderBlockCausal3D",),
+        up_block_types: Tuple[str] = ("UpDecoderBlockCausal3D",),
+        block_out_channels: Tuple[int] = (64,),
+        layers_per_block: int = 1,
+        act_fn: str = "silu",
+        latent_channels: int = 4,
+        norm_num_groups: int = 32,
+        sample_size: int = 32,
+        sample_tsize: int = 64,
+        scaling_factor: float = 0.18215,
+        force_upcast: float = True,
+        spatial_compression_ratio: int = 8,
+        time_compression_ratio: int = 4,
+        mid_block_add_attention: bool = True,
+    ):
+        super().__init__()
+
+        self.time_compression_ratio = time_compression_ratio
+
+        self.encoder = EncoderCausal3D(
+            in_channels=in_channels,
+            out_channels=latent_channels,
+            down_block_types=down_block_types,
+            block_out_channels=block_out_channels,
+            layers_per_block=layers_per_block,
+            act_fn=act_fn,
+            norm_num_groups=norm_num_groups,
+            double_z=True,
+            time_compression_ratio=time_compression_ratio,
+            spatial_compression_ratio=spatial_compression_ratio,
+            mid_block_add_attention=mid_block_add_attention,
+        )
+
+        self.decoder = DecoderCausal3D(
+            in_channels=latent_channels,
+            out_channels=out_channels,
+            up_block_types=up_block_types,
+            block_out_channels=block_out_channels,
+            layers_per_block=layers_per_block,
+            norm_num_groups=norm_num_groups,
+            act_fn=act_fn,
+            time_compression_ratio=time_compression_ratio,
+            spatial_compression_ratio=spatial_compression_ratio,
+            mid_block_add_attention=mid_block_add_attention,
+        )
+
+        self.quant_conv = nn.Conv3d(2 * latent_channels, 2 * latent_channels, kernel_size=1)
+        self.post_quant_conv = nn.Conv3d(latent_channels, latent_channels, kernel_size=1)
+
+        self.use_slicing = False
+        self.use_spatial_tiling = False
+        self.use_temporal_tiling = False
+
+        # only relevant if vae tiling is enabled
+        self.tile_sample_min_tsize = sample_tsize
+        self.tile_latent_min_tsize = sample_tsize // time_compression_ratio
+
+        self.tile_sample_min_size = self.config.sample_size
+        sample_size = (
+            self.config.sample_size[0]
+            if isinstance(self.config.sample_size, (list, tuple))
+            else self.config.sample_size
+        )
+        self.tile_latent_min_size = int(sample_size / (2 ** (len(self.config.block_out_channels) - 1)))
+        self.tile_overlap_factor = 0.25
+
+    def _set_gradient_checkpointing(self, module, value=False):
+        if isinstance(module, (EncoderCausal3D, DecoderCausal3D)):
+            module.gradient_checkpointing = value
+
+    def enable_temporal_tiling(self, use_tiling: bool = True):
+        self.use_temporal_tiling = use_tiling
+
+    def disable_temporal_tiling(self):
+        self.enable_temporal_tiling(False)
+
+    def enable_spatial_tiling(self, use_tiling: bool = True):
+        self.use_spatial_tiling = use_tiling
+
+    def disable_spatial_tiling(self):
+        self.enable_spatial_tiling(False)
+
+    def enable_tiling(self, use_tiling: bool = True):
+        r"""
+        Enable tiled VAE decoding. When this option is enabled, the VAE will split the input tensor into tiles to
+        compute decoding and encoding in several steps. This is useful for saving a large amount of memory and to allow
+        processing larger videos.
+        """
+        self.enable_spatial_tiling(use_tiling)
+        self.enable_temporal_tiling(use_tiling)
+
+    def disable_tiling(self):
+        r"""
+        Disable tiled VAE decoding. If `enable_tiling` was previously enabled, this method will go back to computing
+        decoding in one step.
+        """
+        self.disable_spatial_tiling()
+        self.disable_temporal_tiling()
+
+    def enable_slicing(self):
+        r"""
+        Enable sliced VAE decoding. When this option is enabled, the VAE will split the input tensor in slices to
+        compute decoding in several steps. This is useful to save some memory and allow larger batch sizes.
+        """
+        self.use_slicing = True
+
+    def disable_slicing(self):
+        r"""
+        Disable sliced VAE decoding. If `enable_slicing` was previously enabled, this method will go back to computing
+        decoding in one step.
+        """
+        self.use_slicing = False
+
+    @property
+    # Copied from diffusers.models.unet_2d_condition.UNet2DConditionModel.attn_processors
+    def attn_processors(self) -> Dict[str, AttentionProcessor]:
+        r"""
+        Returns:
+            `dict` of attention processors: A dictionary containing all attention processors used in the model with
+            indexed by its weight name.
+        """
+        # set recursively
+        processors = {}
+
+        def fn_recursive_add_processors(name: str, module: torch.nn.Module, processors: Dict[str, AttentionProcessor]):
+            if hasattr(module, "get_processor"):
+                processors[f"{name}.processor"] = module.get_processor(return_deprecated_lora=True)
+
+            for sub_name, child in module.named_children():
+                fn_recursive_add_processors(f"{name}.{sub_name}", child, processors)
+
+            return processors
+
+        for name, module in self.named_children():
+            fn_recursive_add_processors(name, module, processors)
+
+        return processors
+
+    # Copied from diffusers.models.unet_2d_condition.UNet2DConditionModel.set_attn_processor
+    def set_attn_processor(
+        self, processor: Union[AttentionProcessor, Dict[str, AttentionProcessor]], _remove_lora=False
+    ):
+        r"""
+        Sets the attention processor to use to compute attention.
+
+        Parameters:
+            processor (`dict` of `AttentionProcessor` or only `AttentionProcessor`):
+                The instantiated processor class or a dictionary of processor classes that will be set as the processor
+                for **all** `Attention` layers.
+
+                If `processor` is a dict, the key needs to define the path to the corresponding cross attention
+                processor. This is strongly recommended when setting trainable attention processors.
+
+        """
+        count = len(self.attn_processors.keys())
+
+        if isinstance(processor, dict) and len(processor) != count:
+            raise ValueError(
+                f"A dict of processors was passed, but the number of processors {len(processor)} does not match the"
+                f" number of attention layers: {count}. Please make sure to pass {count} processor classes."
+            )
+
+        def fn_recursive_attn_processor(name: str, module: torch.nn.Module, processor):
+            if hasattr(module, "set_processor"):
+                if not isinstance(processor, dict):
+                    module.set_processor(processor, _remove_lora=_remove_lora)
+                else:
+                    module.set_processor(processor.pop(f"{name}.processor"), _remove_lora=_remove_lora)
+
+            for sub_name, child in module.named_children():
+                fn_recursive_attn_processor(f"{name}.{sub_name}", child, processor)
+
+        for name, module in self.named_children():
+            fn_recursive_attn_processor(name, module, processor)
+
+    # Copied from diffusers.models.unet_2d_condition.UNet2DConditionModel.set_default_attn_processor
+    def set_default_attn_processor(self):
+        """
+        Disables custom attention processors and sets the default attention implementation.
+        """
+        if all(proc.__class__ in ADDED_KV_ATTENTION_PROCESSORS for proc in self.attn_processors.values()):
+            processor = AttnAddedKVProcessor()
+        elif all(proc.__class__ in CROSS_ATTENTION_PROCESSORS for proc in self.attn_processors.values()):
+            processor = AttnProcessor()
+        else:
+            raise ValueError(
+                f"Cannot call `set_default_attn_processor` when attention processors are of type {next(iter(self.attn_processors.values()))}"
+            )
+
+        self.set_attn_processor(processor, _remove_lora=True)
+
+    @apply_forward_hook
+    def encode(
+        self, x: torch.FloatTensor, return_dict: bool = True
+    ) -> Union[AutoencoderKLOutput, Tuple[DiagonalGaussianDistribution]]:
+        """
+        Encode a batch of images/videos into latents.
+
+        Args:
+            x (`torch.FloatTensor`): Input batch of images/videos.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether to return a [`~models.autoencoder_kl.AutoencoderKLOutput`] instead of a plain tuple.
+
+        Returns:
+                The latent representations of the encoded images/videos. If `return_dict` is True, a
+                [`~models.autoencoder_kl.AutoencoderKLOutput`] is returned, otherwise a plain `tuple` is returned.
+        """
+        assert len(x.shape) == 5, "The input tensor should have 5 dimensions."
+
+        if self.use_temporal_tiling and x.shape[2] > self.tile_sample_min_tsize:
+            return self.temporal_tiled_encode(x, return_dict=return_dict)
+
+        if self.use_spatial_tiling and (x.shape[-1] > self.tile_sample_min_size or x.shape[-2] > self.tile_sample_min_size):
+            return self.spatial_tiled_encode(x, return_dict=return_dict)
+
+        if self.use_slicing and x.shape[0] > 1:
+            encoded_slices = [self.encoder(x_slice) for x_slice in x.split(1)]
+            h = torch.cat(encoded_slices)
+        else:
+            h = self.encoder(x)
+
+        moments = self.quant_conv(h)
+        posterior = DiagonalGaussianDistribution(moments)
+
+        if not return_dict:
+            return (posterior,)
+
+        return AutoencoderKLOutput(latent_dist=posterior)
+
+    def _decode(self, z: torch.FloatTensor, return_dict: bool = True) -> Union[DecoderOutput, torch.FloatTensor]:
+        assert len(z.shape) == 5, "The input tensor should have 5 dimensions."
+
+        if self.use_temporal_tiling and z.shape[2] > self.tile_latent_min_tsize:
+            return self.temporal_tiled_decode(z, return_dict=return_dict)
+
+        if self.use_spatial_tiling and (z.shape[-1] > self.tile_latent_min_size or z.shape[-2] > self.tile_latent_min_size):
+            return self.spatial_tiled_decode(z, return_dict=return_dict)
+
+        z = self.post_quant_conv(z)
+        dec = self.decoder(z)
+
+        if not return_dict:
+            return (dec,)
+
+        return DecoderOutput(sample=dec)
+
+    @apply_forward_hook
+    def decode(
+        self, z: torch.FloatTensor, return_dict: bool = True, generator=None
+    ) -> Union[DecoderOutput, torch.FloatTensor]:
+        """
+        Decode a batch of images/videos.
+
+        Args:
+            z (`torch.FloatTensor`): Input batch of latent vectors.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether to return a [`~models.vae.DecoderOutput`] instead of a plain tuple.
+
+        Returns:
+            [`~models.vae.DecoderOutput`] or `tuple`:
+                If return_dict is True, a [`~models.vae.DecoderOutput`] is returned, otherwise a plain `tuple` is
+                returned.
+
+        """
+        if self.use_slicing and z.shape[0] > 1:
+            decoded_slices = [self._decode(z_slice).sample for z_slice in z.split(1)]
+            decoded = torch.cat(decoded_slices)
+        else:
+            decoded = self._decode(z).sample
+
+        if not return_dict:
+            return (decoded,)
+
+        return DecoderOutput(sample=decoded)
+
+    def blend_v(self, a: torch.Tensor, b: torch.Tensor, blend_extent: int) -> torch.Tensor:
+        blend_extent = min(a.shape[-2], b.shape[-2], blend_extent)
+        for y in range(blend_extent):
+            b[:, :, :, y, :] = a[:, :, :, -blend_extent + y, :] * (1 - y / blend_extent) + b[:, :, :, y, :] * (y / blend_extent)
+        return b
+
+    def blend_h(self, a: torch.Tensor, b: torch.Tensor, blend_extent: int) -> torch.Tensor:
+        blend_extent = min(a.shape[-1], b.shape[-1], blend_extent)
+        for x in range(blend_extent):
+            b[:, :, :, :, x] = a[:, :, :, :, -blend_extent + x] * (1 - x / blend_extent) + b[:, :, :, :, x] * (x / blend_extent)
+        return b
+
+    def blend_t(self, a: torch.Tensor, b: torch.Tensor, blend_extent: int) -> torch.Tensor:
+        blend_extent = min(a.shape[-3], b.shape[-3], blend_extent)
+        for x in range(blend_extent):
+            b[:, :, x, :, :] = a[:, :, -blend_extent + x, :, :] * (1 - x / blend_extent) + b[:, :, x, :, :] * (x / blend_extent)
+        return b
+
+    def spatial_tiled_encode(self, x: torch.FloatTensor, return_dict: bool = True, return_moments: bool = False) -> AutoencoderKLOutput:
+        r"""Encode a batch of images/videos using a tiled encoder.
+
+        When this option is enabled, the VAE will split the input tensor into tiles to compute encoding in several
+        steps. This is useful to keep memory use constant regardless of image/videos size. The end result of tiled encoding is
+        different from non-tiled encoding because each tile uses a different encoder. To avoid tiling artifacts, the
+        tiles overlap and are blended together to form a smooth output. You may still see tile-sized changes in the
+        output, but they should be much less noticeable.
+
+        Args:
+            x (`torch.FloatTensor`): Input batch of images/videos.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`~models.autoencoder_kl.AutoencoderKLOutput`] instead of a plain tuple.
+
+        Returns:
+            [`~models.autoencoder_kl.AutoencoderKLOutput`] or `tuple`:
+                If return_dict is True, a [`~models.autoencoder_kl.AutoencoderKLOutput`] is returned, otherwise a plain
+                `tuple` is returned.
+        """
+        overlap_size = int(self.tile_sample_min_size * (1 - self.tile_overlap_factor))
+        blend_extent = int(self.tile_latent_min_size * self.tile_overlap_factor)
+        row_limit = self.tile_latent_min_size - blend_extent
+
+        # Split video into tiles and encode them separately.
+        rows = []
+        for i in range(0, x.shape[-2], overlap_size):
+            row = []
+            for j in range(0, x.shape[-1], overlap_size):
+                tile = x[:, :, :, i: i + self.tile_sample_min_size, j: j + self.tile_sample_min_size]
+                tile = self.encoder(tile)
+                tile = self.quant_conv(tile)
+                row.append(tile)
+            rows.append(row)
+        result_rows = []
+        for i, row in enumerate(rows):
+            result_row = []
+            for j, tile in enumerate(row):
+                # blend the above tile and the left tile
+                # to the current tile and add the current tile to the result row
+                if i > 0:
+                    tile = self.blend_v(rows[i - 1][j], tile, blend_extent)
+                if j > 0:
+                    tile = self.blend_h(row[j - 1], tile, blend_extent)
+                result_row.append(tile[:, :, :, :row_limit, :row_limit])
+            result_rows.append(torch.cat(result_row, dim=-1))
+
+        moments = torch.cat(result_rows, dim=-2)
+        if return_moments:
+            return moments
+
+        posterior = DiagonalGaussianDistribution(moments)
+        if not return_dict:
+            return (posterior,)
+
+        return AutoencoderKLOutput(latent_dist=posterior)
+
+    def spatial_tiled_decode(self, z: torch.FloatTensor, return_dict: bool = True) -> Union[DecoderOutput, torch.FloatTensor]:
+        r"""
+        Decode a batch of images/videos using a tiled decoder.
+
+        Args:
+            z (`torch.FloatTensor`): Input batch of latent vectors.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`~models.vae.DecoderOutput`] instead of a plain tuple.
+
+        Returns:
+            [`~models.vae.DecoderOutput`] or `tuple`:
+                If return_dict is True, a [`~models.vae.DecoderOutput`] is returned, otherwise a plain `tuple` is
+                returned.
+        """
+        overlap_size = int(self.tile_latent_min_size * (1 - self.tile_overlap_factor))
+        blend_extent = int(self.tile_sample_min_size * self.tile_overlap_factor)
+        row_limit = self.tile_sample_min_size - blend_extent
+
+        # Split z into overlapping tiles and decode them separately.
+        # The tiles have an overlap to avoid seams between tiles.
+        rows = []
+        for i in range(0, z.shape[-2], overlap_size):
+            row = []
+            for j in range(0, z.shape[-1], overlap_size):
+                tile = z[:, :, :, i: i + self.tile_latent_min_size, j: j + self.tile_latent_min_size]
+                tile = self.post_quant_conv(tile)
+                decoded = self.decoder(tile)
+                row.append(decoded)
+            rows.append(row)
+        result_rows = []
+        for i, row in enumerate(rows):
+            result_row = []
+            for j, tile in enumerate(row):
+                # blend the above tile and the left tile
+                # to the current tile and add the current tile to the result row
+                if i > 0:
+                    tile = self.blend_v(rows[i - 1][j], tile, blend_extent)
+                if j > 0:
+                    tile = self.blend_h(row[j - 1], tile, blend_extent)
+                result_row.append(tile[:, :, :, :row_limit, :row_limit])
+            result_rows.append(torch.cat(result_row, dim=-1))
+
+        dec = torch.cat(result_rows, dim=-2)
+        if not return_dict:
+            return (dec,)
+
+        return DecoderOutput(sample=dec)
+
+    def temporal_tiled_encode(self, x: torch.FloatTensor, return_dict: bool = True) -> AutoencoderKLOutput:
+
+        B, C, T, H, W = x.shape
+        overlap_size = int(self.tile_sample_min_tsize * (1 - self.tile_overlap_factor))
+        blend_extent = int(self.tile_latent_min_tsize * self.tile_overlap_factor)
+        t_limit = self.tile_latent_min_tsize - blend_extent
+
+        # Split the video into tiles and encode them separately.
+        row = []
+        for i in range(0, T, overlap_size):
+            tile = x[:, :, i: i + self.tile_sample_min_tsize + 1, :, :]
+            if self.use_spatial_tiling and (tile.shape[-1] > self.tile_sample_min_size or tile.shape[-2] > self.tile_sample_min_size):
+                tile = self.spatial_tiled_encode(tile, return_moments=True)
+            else:
+                tile = self.encoder(tile)
+                tile = self.quant_conv(tile)
+            if i > 0:
+                tile = tile[:, :, 1:, :, :]
+            row.append(tile)
+        result_row = []
+        for i, tile in enumerate(row):
+            if i > 0:
+                tile = self.blend_t(row[i - 1], tile, blend_extent)
+                result_row.append(tile[:, :, :t_limit, :, :])
+            else:
+                result_row.append(tile[:, :, :t_limit + 1, :, :])
+
+        moments = torch.cat(result_row, dim=2)
+        posterior = DiagonalGaussianDistribution(moments)
+
+        if not return_dict:
+            return (posterior,)
+
+        return AutoencoderKLOutput(latent_dist=posterior)
+
+    def temporal_tiled_decode(self, z: torch.FloatTensor, return_dict: bool = True) -> Union[DecoderOutput, torch.FloatTensor]:
+        # Split z into overlapping tiles and decode them separately.
+
+        B, C, T, H, W = z.shape
+        overlap_size = int(self.tile_latent_min_tsize * (1 - self.tile_overlap_factor))
+        blend_extent = int(self.tile_sample_min_tsize * self.tile_overlap_factor)
+        t_limit = self.tile_sample_min_tsize - blend_extent
+
+        row = []
+        for i in range(0, T, overlap_size):
+            tile = z[:, :, i: i + self.tile_latent_min_tsize + 1, :, :]
+            if self.use_spatial_tiling and (tile.shape[-1] > self.tile_latent_min_size or tile.shape[-2] > self.tile_latent_min_size):
+                decoded = self.spatial_tiled_decode(tile, return_dict=True).sample
+            else:
+                tile = self.post_quant_conv(tile)
+                decoded = self.decoder(tile)
+            if i > 0:
+                decoded = decoded[:, :, 1:, :, :]
+            row.append(decoded)
+        result_row = []
+        for i, tile in enumerate(row):
+            if i > 0:
+                tile = self.blend_t(row[i - 1], tile, blend_extent)
+                result_row.append(tile[:, :, :t_limit, :, :])
+            else:
+                result_row.append(tile[:, :, :t_limit + 1, :, :])
+
+        dec = torch.cat(result_row, dim=2)
+        if not return_dict:
+            return (dec,)
+
+        return DecoderOutput(sample=dec)
+
+    def forward(
+        self,
+        sample: torch.FloatTensor,
+        sample_posterior: bool = False,
+        return_dict: bool = True,
+        return_posterior: bool = False,
+        generator: Optional[torch.Generator] = None,
+    ) -> Union[DecoderOutput2, torch.FloatTensor]:
+        r"""
+        Args:
+            sample (`torch.FloatTensor`): Input sample.
+            sample_posterior (`bool`, *optional*, defaults to `False`):
+                Whether to sample from the posterior.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`DecoderOutput`] instead of a plain tuple.
+        """
+        x = sample
+        posterior = self.encode(x).latent_dist
+        if sample_posterior:
+            z = posterior.sample(generator=generator)
+        else:
+            z = posterior.mode()
+        dec = self.decode(z).sample
+
+        if not return_dict:
+            if return_posterior:
+                return (dec, posterior)
+            else:
+                return (dec,)
+        if return_posterior:
+            return DecoderOutput2(sample=dec, posterior=posterior)
+        else:
+            return DecoderOutput2(sample=dec)
+
+    # Copied from diffusers.models.unet_2d_condition.UNet2DConditionModel.fuse_qkv_projections
+    def fuse_qkv_projections(self):
+        """
+        Enables fused QKV projections. For self-attention modules, all projection matrices (i.e., query,
+        key, value) are fused. For cross-attention modules, key and value projection matrices are fused.
+
+        <Tip warning={true}>
+
+        This API is 🧪 experimental.
+
+        </Tip>
+        """
+        self.original_attn_processors = None
+
+        for _, attn_processor in self.attn_processors.items():
+            if "Added" in str(attn_processor.__class__.__name__):
+                raise ValueError("`fuse_qkv_projections()` is not supported for models having added KV projections.")
+
+        self.original_attn_processors = self.attn_processors
+
+        for module in self.modules():
+            if isinstance(module, Attention):
+                module.fuse_projections(fuse=True)
+
+    # Copied from diffusers.models.unet_2d_condition.UNet2DConditionModel.unfuse_qkv_projections
+    def unfuse_qkv_projections(self):
+        """Disables the fused QKV projection if enabled.
+
+        <Tip warning={true}>
+
+        This API is 🧪 experimental.
+
+        </Tip>
+
+        """
+        if self.original_attn_processors is not None:
+            self.set_attn_processor(self.original_attn_processors)

hyvideo/vae/unet_causal_3d_blocks.py

@@ -0,0 +1,764 @@
+# Copyright 2024 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+#
+# Modified from diffusers==0.29.2
+#
+# ==============================================================================
+
+from typing import Optional, Tuple, Union
+
+import torch
+import torch.nn.functional as F
+from torch import nn
+from einops import rearrange
+
+from diffusers.utils import logging
+from diffusers.models.activations import get_activation
+from diffusers.models.attention_processor import SpatialNorm
+from diffusers.models.attention_processor import Attention
+from diffusers.models.normalization import AdaGroupNorm
+from diffusers.models.normalization import RMSNorm
+
+logger = logging.get_logger(__name__)  # pylint: disable=invalid-name
+
+
+def prepare_causal_attention_mask(n_frame: int, n_hw: int, dtype, device, batch_size: int = None):
+    seq_len = n_frame * n_hw
+    mask = torch.full((seq_len, seq_len), float("-inf"), dtype=dtype, device=device)
+    for i in range(seq_len):
+        i_frame = i // n_hw
+        mask[i, : (i_frame + 1) * n_hw] = 0
+    if batch_size is not None:
+        mask = mask.unsqueeze(0).expand(batch_size, -1, -1)
+    return mask
+
+
+class CausalConv3d(nn.Module):
+    """
+    Implements a causal 3D convolution layer where each position only depends on previous timesteps and current spatial locations.
+    This maintains temporal causality in video generation tasks.
+    """
+
+    def __init__(
+        self,
+        chan_in,
+        chan_out,
+        kernel_size: Union[int, Tuple[int, int, int]],
+        stride: Union[int, Tuple[int, int, int]] = 1,
+        dilation: Union[int, Tuple[int, int, int]] = 1,
+        pad_mode='replicate',
+        **kwargs
+    ):
+        super().__init__()
+
+        self.pad_mode = pad_mode
+        padding = (kernel_size // 2, kernel_size // 2, kernel_size // 2, kernel_size // 2, kernel_size - 1, 0)  # W, H, T
+        self.time_causal_padding = padding
+
+        self.conv = nn.Conv3d(chan_in, chan_out, kernel_size, stride=stride, dilation=dilation, **kwargs)
+
+    def forward(self, x):
+        x = F.pad(x, self.time_causal_padding, mode=self.pad_mode)
+        return self.conv(x)
+
+
+class UpsampleCausal3D(nn.Module):
+    """
+    A 3D upsampling layer with an optional convolution.
+    """
+
+    def __init__(
+        self,
+        channels: int,
+        use_conv: bool = False,
+        use_conv_transpose: bool = False,
+        out_channels: Optional[int] = None,
+        name: str = "conv",
+        kernel_size: Optional[int] = None,
+        padding=1,
+        norm_type=None,
+        eps=None,
+        elementwise_affine=None,
+        bias=True,
+        interpolate=True,
+        upsample_factor=(2, 2, 2),
+    ):
+        super().__init__()
+        self.channels = channels
+        self.out_channels = out_channels or channels
+        self.use_conv = use_conv
+        self.use_conv_transpose = use_conv_transpose
+        self.name = name
+        self.interpolate = interpolate
+        self.upsample_factor = upsample_factor
+
+        if norm_type == "ln_norm":
+            self.norm = nn.LayerNorm(channels, eps, elementwise_affine)
+        elif norm_type == "rms_norm":
+            self.norm = RMSNorm(channels, eps, elementwise_affine)
+        elif norm_type is None:
+            self.norm = None
+        else:
+            raise ValueError(f"unknown norm_type: {norm_type}")
+
+        conv = None
+        if use_conv_transpose:
+            raise NotImplementedError
+        elif use_conv:
+            if kernel_size is None:
+                kernel_size = 3
+            conv = CausalConv3d(self.channels, self.out_channels, kernel_size=kernel_size, bias=bias)
+
+        if name == "conv":
+            self.conv = conv
+        else:
+            self.Conv2d_0 = conv
+
+    def forward(
+        self,
+        hidden_states: torch.FloatTensor,
+        output_size: Optional[int] = None,
+        scale: float = 1.0,
+    ) -> torch.FloatTensor:
+        assert hidden_states.shape[1] == self.channels
+
+        if self.norm is not None:
+            raise NotImplementedError
+
+        if self.use_conv_transpose:
+            return self.conv(hidden_states)
+
+        # Cast to float32 to as 'upsample_nearest2d_out_frame' op does not support bfloat16
+        dtype = hidden_states.dtype
+        if dtype == torch.bfloat16:
+            hidden_states = hidden_states.to(torch.float32)
+
+        # upsample_nearest_nhwc fails with large batch sizes. see https://github.com/huggingface/diffusers/issues/984
+        if hidden_states.shape[0] >= 64:
+            hidden_states = hidden_states.contiguous()
+
+        # if `output_size` is passed we force the interpolation output
+        # size and do not make use of `scale_factor=2`
+        if self.interpolate:
+            B, C, T, H, W = hidden_states.shape
+            first_h, other_h = hidden_states.split((1, T - 1), dim=2)
+            if output_size is None:
+                if T > 1:
+                    other_h = F.interpolate(other_h, scale_factor=self.upsample_factor, mode="nearest")
+
+                first_h = first_h.squeeze(2)
+                first_h = F.interpolate(first_h, scale_factor=self.upsample_factor[1:], mode="nearest")
+                first_h = first_h.unsqueeze(2)
+            else:
+                raise NotImplementedError
+
+            if T > 1:
+                hidden_states = torch.cat((first_h, other_h), dim=2)
+            else:
+                hidden_states = first_h
+
+        # If the input is bfloat16, we cast back to bfloat16
+        if dtype == torch.bfloat16:
+            hidden_states = hidden_states.to(dtype)
+
+        if self.use_conv:
+            if self.name == "conv":
+                hidden_states = self.conv(hidden_states)
+            else:
+                hidden_states = self.Conv2d_0(hidden_states)
+
+        return hidden_states
+
+
+class DownsampleCausal3D(nn.Module):
+    """
+    A 3D downsampling layer with an optional convolution.
+    """
+
+    def __init__(
+        self,
+        channels: int,
+        use_conv: bool = False,
+        out_channels: Optional[int] = None,
+        padding: int = 1,
+        name: str = "conv",
+        kernel_size=3,
+        norm_type=None,
+        eps=None,
+        elementwise_affine=None,
+        bias=True,
+        stride=2,
+    ):
+        super().__init__()
+        self.channels = channels
+        self.out_channels = out_channels or channels
+        self.use_conv = use_conv
+        self.padding = padding
+        stride = stride
+        self.name = name
+
+        if norm_type == "ln_norm":
+            self.norm = nn.LayerNorm(channels, eps, elementwise_affine)
+        elif norm_type == "rms_norm":
+            self.norm = RMSNorm(channels, eps, elementwise_affine)
+        elif norm_type is None:
+            self.norm = None
+        else:
+            raise ValueError(f"unknown norm_type: {norm_type}")
+
+        if use_conv:
+            conv = CausalConv3d(
+                self.channels, self.out_channels, kernel_size=kernel_size, stride=stride, bias=bias
+            )
+        else:
+            raise NotImplementedError
+
+        if name == "conv":
+            self.Conv2d_0 = conv
+            self.conv = conv
+        elif name == "Conv2d_0":
+            self.conv = conv
+        else:
+            self.conv = conv
+
+    def forward(self, hidden_states: torch.FloatTensor, scale: float = 1.0) -> torch.FloatTensor:
+        assert hidden_states.shape[1] == self.channels
+
+        if self.norm is not None:
+            hidden_states = self.norm(hidden_states.permute(0, 2, 3, 1)).permute(0, 3, 1, 2)
+
+        assert hidden_states.shape[1] == self.channels
+
+        hidden_states = self.conv(hidden_states)
+
+        return hidden_states
+
+
+class ResnetBlockCausal3D(nn.Module):
+    r"""
+    A Resnet block.
+    """
+
+    def __init__(
+        self,
+        *,
+        in_channels: int,
+        out_channels: Optional[int] = None,
+        conv_shortcut: bool = False,
+        dropout: float = 0.0,
+        temb_channels: int = 512,
+        groups: int = 32,
+        groups_out: Optional[int] = None,
+        pre_norm: bool = True,
+        eps: float = 1e-6,
+        non_linearity: str = "swish",
+        skip_time_act: bool = False,
+        # default, scale_shift, ada_group, spatial
+        time_embedding_norm: str = "default",
+        kernel: Optional[torch.FloatTensor] = None,
+        output_scale_factor: float = 1.0,
+        use_in_shortcut: Optional[bool] = None,
+        up: bool = False,
+        down: bool = False,
+        conv_shortcut_bias: bool = True,
+        conv_3d_out_channels: Optional[int] = None,
+    ):
+        super().__init__()
+        self.pre_norm = pre_norm
+        self.pre_norm = True
+        self.in_channels = in_channels
+        out_channels = in_channels if out_channels is None else out_channels
+        self.out_channels = out_channels
+        self.use_conv_shortcut = conv_shortcut
+        self.up = up
+        self.down = down
+        self.output_scale_factor = output_scale_factor
+        self.time_embedding_norm = time_embedding_norm
+        self.skip_time_act = skip_time_act
+
+        linear_cls = nn.Linear
+
+        if groups_out is None:
+            groups_out = groups
+
+        if self.time_embedding_norm == "ada_group":
+            self.norm1 = AdaGroupNorm(temb_channels, in_channels, groups, eps=eps)
+        elif self.time_embedding_norm == "spatial":
+            self.norm1 = SpatialNorm(in_channels, temb_channels)
+        else:
+            self.norm1 = torch.nn.GroupNorm(num_groups=groups, num_channels=in_channels, eps=eps, affine=True)
+
+        self.conv1 = CausalConv3d(in_channels, out_channels, kernel_size=3, stride=1)
+
+        if temb_channels is not None:
+            if self.time_embedding_norm == "default":
+                self.time_emb_proj = linear_cls(temb_channels, out_channels)
+            elif self.time_embedding_norm == "scale_shift":
+                self.time_emb_proj = linear_cls(temb_channels, 2 * out_channels)
+            elif self.time_embedding_norm == "ada_group" or self.time_embedding_norm == "spatial":
+                self.time_emb_proj = None
+            else:
+                raise ValueError(f"Unknown time_embedding_norm : {self.time_embedding_norm} ")
+        else:
+            self.time_emb_proj = None
+
+        if self.time_embedding_norm == "ada_group":
+            self.norm2 = AdaGroupNorm(temb_channels, out_channels, groups_out, eps=eps)
+        elif self.time_embedding_norm == "spatial":
+            self.norm2 = SpatialNorm(out_channels, temb_channels)
+        else:
+            self.norm2 = torch.nn.GroupNorm(num_groups=groups_out, num_channels=out_channels, eps=eps, affine=True)
+
+        self.dropout = torch.nn.Dropout(dropout)
+        conv_3d_out_channels = conv_3d_out_channels or out_channels
+        self.conv2 = CausalConv3d(out_channels, conv_3d_out_channels, kernel_size=3, stride=1)
+
+        self.nonlinearity = get_activation(non_linearity)
+
+        self.upsample = self.downsample = None
+        if self.up:
+            self.upsample = UpsampleCausal3D(in_channels, use_conv=False)
+        elif self.down:
+            self.downsample = DownsampleCausal3D(in_channels, use_conv=False, name="op")
+
+        self.use_in_shortcut = self.in_channels != conv_3d_out_channels if use_in_shortcut is None else use_in_shortcut
+
+        self.conv_shortcut = None
+        if self.use_in_shortcut:
+            self.conv_shortcut = CausalConv3d(
+                in_channels,
+                conv_3d_out_channels,
+                kernel_size=1,
+                stride=1,
+                bias=conv_shortcut_bias,
+            )
+
+    def forward(
+        self,
+        input_tensor: torch.FloatTensor,
+        temb: torch.FloatTensor,
+        scale: float = 1.0,
+    ) -> torch.FloatTensor:
+        hidden_states = input_tensor
+
+        if self.time_embedding_norm == "ada_group" or self.time_embedding_norm == "spatial":
+            hidden_states = self.norm1(hidden_states, temb)
+        else:
+            hidden_states = self.norm1(hidden_states)
+
+        hidden_states = self.nonlinearity(hidden_states)
+
+        if self.upsample is not None:
+            # upsample_nearest_nhwc fails with large batch sizes. see https://github.com/huggingface/diffusers/issues/984
+            if hidden_states.shape[0] >= 64:
+                input_tensor = input_tensor.contiguous()
+                hidden_states = hidden_states.contiguous()
+            input_tensor = (
+                self.upsample(input_tensor, scale=scale)
+            )
+            hidden_states = (
+                self.upsample(hidden_states, scale=scale)
+            )
+        elif self.downsample is not None:
+            input_tensor = (
+                self.downsample(input_tensor, scale=scale)
+            )
+            hidden_states = (
+                self.downsample(hidden_states, scale=scale)
+            )
+
+        hidden_states = self.conv1(hidden_states)
+
+        if self.time_emb_proj is not None:
+            if not self.skip_time_act:
+                temb = self.nonlinearity(temb)
+            temb = (
+                self.time_emb_proj(temb, scale)[:, :, None, None]
+            )
+
+        if temb is not None and self.time_embedding_norm == "default":
+            hidden_states = hidden_states + temb
+
+        if self.time_embedding_norm == "ada_group" or self.time_embedding_norm == "spatial":
+            hidden_states = self.norm2(hidden_states, temb)
+        else:
+            hidden_states = self.norm2(hidden_states)
+
+        if temb is not None and self.time_embedding_norm == "scale_shift":
+            scale, shift = torch.chunk(temb, 2, dim=1)
+            hidden_states = hidden_states * (1 + scale) + shift
+
+        hidden_states = self.nonlinearity(hidden_states)
+
+        hidden_states = self.dropout(hidden_states)
+        hidden_states = self.conv2(hidden_states)
+
+        if self.conv_shortcut is not None:
+            input_tensor = (
+                self.conv_shortcut(input_tensor)
+            )
+
+        output_tensor = (input_tensor + hidden_states) / self.output_scale_factor
+
+        return output_tensor
+
+
+def get_down_block3d(
+    down_block_type: str,
+    num_layers: int,
+    in_channels: int,
+    out_channels: int,
+    temb_channels: int,
+    add_downsample: bool,
+    downsample_stride: int,
+    resnet_eps: float,
+    resnet_act_fn: str,
+    transformer_layers_per_block: int = 1,
+    num_attention_heads: Optional[int] = None,
+    resnet_groups: Optional[int] = None,
+    cross_attention_dim: Optional[int] = None,
+    downsample_padding: Optional[int] = None,
+    dual_cross_attention: bool = False,
+    use_linear_projection: bool = False,
+    only_cross_attention: bool = False,
+    upcast_attention: bool = False,
+    resnet_time_scale_shift: str = "default",
+    attention_type: str = "default",
+    resnet_skip_time_act: bool = False,
+    resnet_out_scale_factor: float = 1.0,
+    cross_attention_norm: Optional[str] = None,
+    attention_head_dim: Optional[int] = None,
+    downsample_type: Optional[str] = None,
+    dropout: float = 0.0,
+):
+    # If attn head dim is not defined, we default it to the number of heads
+    if attention_head_dim is None:
+        logger.warn(
+            f"It is recommended to provide `attention_head_dim` when calling `get_down_block`. Defaulting `attention_head_dim` to {num_attention_heads}."
+        )
+        attention_head_dim = num_attention_heads
+
+    down_block_type = down_block_type[7:] if down_block_type.startswith("UNetRes") else down_block_type
+    if down_block_type == "DownEncoderBlockCausal3D":
+        return DownEncoderBlockCausal3D(
+            num_layers=num_layers,
+            in_channels=in_channels,
+            out_channels=out_channels,
+            dropout=dropout,
+            add_downsample=add_downsample,
+            downsample_stride=downsample_stride,
+            resnet_eps=resnet_eps,
+            resnet_act_fn=resnet_act_fn,
+            resnet_groups=resnet_groups,
+            downsample_padding=downsample_padding,
+            resnet_time_scale_shift=resnet_time_scale_shift,
+        )
+    raise ValueError(f"{down_block_type} does not exist.")
+
+
+def get_up_block3d(
+    up_block_type: str,
+    num_layers: int,
+    in_channels: int,
+    out_channels: int,
+    prev_output_channel: int,
+    temb_channels: int,
+    add_upsample: bool,
+    upsample_scale_factor: Tuple,
+    resnet_eps: float,
+    resnet_act_fn: str,
+    resolution_idx: Optional[int] = None,
+    transformer_layers_per_block: int = 1,
+    num_attention_heads: Optional[int] = None,
+    resnet_groups: Optional[int] = None,
+    cross_attention_dim: Optional[int] = None,
+    dual_cross_attention: bool = False,
+    use_linear_projection: bool = False,
+    only_cross_attention: bool = False,
+    upcast_attention: bool = False,
+    resnet_time_scale_shift: str = "default",
+    attention_type: str = "default",
+    resnet_skip_time_act: bool = False,
+    resnet_out_scale_factor: float = 1.0,
+    cross_attention_norm: Optional[str] = None,
+    attention_head_dim: Optional[int] = None,
+    upsample_type: Optional[str] = None,
+    dropout: float = 0.0,
+) -> nn.Module:
+    # If attn head dim is not defined, we default it to the number of heads
+    if attention_head_dim is None:
+        logger.warn(
+            f"It is recommended to provide `attention_head_dim` when calling `get_up_block`. Defaulting `attention_head_dim` to {num_attention_heads}."
+        )
+        attention_head_dim = num_attention_heads
+
+    up_block_type = up_block_type[7:] if up_block_type.startswith("UNetRes") else up_block_type
+    if up_block_type == "UpDecoderBlockCausal3D":
+        return UpDecoderBlockCausal3D(
+            num_layers=num_layers,
+            in_channels=in_channels,
+            out_channels=out_channels,
+            resolution_idx=resolution_idx,
+            dropout=dropout,
+            add_upsample=add_upsample,
+            upsample_scale_factor=upsample_scale_factor,
+            resnet_eps=resnet_eps,
+            resnet_act_fn=resnet_act_fn,
+            resnet_groups=resnet_groups,
+            resnet_time_scale_shift=resnet_time_scale_shift,
+            temb_channels=temb_channels,
+        )
+    raise ValueError(f"{up_block_type} does not exist.")
+
+
+class UNetMidBlockCausal3D(nn.Module):
+    """
+    A 3D UNet mid-block [`UNetMidBlockCausal3D`] with multiple residual blocks and optional attention blocks.
+    """
+
+    def __init__(
+        self,
+        in_channels: int,
+        temb_channels: int,
+        dropout: float = 0.0,
+        num_layers: int = 1,
+        resnet_eps: float = 1e-6,
+        resnet_time_scale_shift: str = "default",  # default, spatial
+        resnet_act_fn: str = "swish",
+        resnet_groups: int = 32,
+        attn_groups: Optional[int] = None,
+        resnet_pre_norm: bool = True,
+        add_attention: bool = True,
+        attention_head_dim: int = 1,
+        output_scale_factor: float = 1.0,
+    ):
+        super().__init__()
+        resnet_groups = resnet_groups if resnet_groups is not None else min(in_channels // 4, 32)
+        self.add_attention = add_attention
+
+        if attn_groups is None:
+            attn_groups = resnet_groups if resnet_time_scale_shift == "default" else None
+
+        # there is always at least one resnet
+        resnets = [
+            ResnetBlockCausal3D(
+                in_channels=in_channels,
+                out_channels=in_channels,
+                temb_channels=temb_channels,
+                eps=resnet_eps,
+                groups=resnet_groups,
+                dropout=dropout,
+                time_embedding_norm=resnet_time_scale_shift,
+                non_linearity=resnet_act_fn,
+                output_scale_factor=output_scale_factor,
+                pre_norm=resnet_pre_norm,
+            )
+        ]
+        attentions = []
+
+        if attention_head_dim is None:
+            logger.warn(
+                f"It is not recommend to pass `attention_head_dim=None`. Defaulting `attention_head_dim` to `in_channels`: {in_channels}."
+            )
+            attention_head_dim = in_channels
+
+        for _ in range(num_layers):
+            if self.add_attention:
+                attentions.append(
+                    Attention(
+                        in_channels,
+                        heads=in_channels // attention_head_dim,
+                        dim_head=attention_head_dim,
+                        rescale_output_factor=output_scale_factor,
+                        eps=resnet_eps,
+                        norm_num_groups=attn_groups,
+                        spatial_norm_dim=temb_channels if resnet_time_scale_shift == "spatial" else None,
+                        residual_connection=True,
+                        bias=True,
+                        upcast_softmax=True,
+                        _from_deprecated_attn_block=True,
+                    )
+                )
+            else:
+                attentions.append(None)
+
+            resnets.append(
+                ResnetBlockCausal3D(
+                    in_channels=in_channels,
+                    out_channels=in_channels,
+                    temb_channels=temb_channels,
+                    eps=resnet_eps,
+                    groups=resnet_groups,
+                    dropout=dropout,
+                    time_embedding_norm=resnet_time_scale_shift,
+                    non_linearity=resnet_act_fn,
+                    output_scale_factor=output_scale_factor,
+                    pre_norm=resnet_pre_norm,
+                )
+            )
+
+        self.attentions = nn.ModuleList(attentions)
+        self.resnets = nn.ModuleList(resnets)
+
+    def forward(self, hidden_states: torch.FloatTensor, temb: Optional[torch.FloatTensor] = None) -> torch.FloatTensor:
+        hidden_states = self.resnets[0](hidden_states, temb)
+        for attn, resnet in zip(self.attentions, self.resnets[1:]):
+            if attn is not None:
+                B, C, T, H, W = hidden_states.shape
+                hidden_states = rearrange(hidden_states, "b c f h w -> b (f h w) c")
+                attention_mask = prepare_causal_attention_mask(
+                    T, H * W, hidden_states.dtype, hidden_states.device, batch_size=B
+                )
+                hidden_states = attn(hidden_states, temb=temb, attention_mask=attention_mask)
+                hidden_states = rearrange(hidden_states, "b (f h w) c -> b c f h w", f=T, h=H, w=W)
+            hidden_states = resnet(hidden_states, temb)
+
+        return hidden_states
+
+
+class DownEncoderBlockCausal3D(nn.Module):
+    def __init__(
+        self,
+        in_channels: int,
+        out_channels: int,
+        dropout: float = 0.0,
+        num_layers: int = 1,
+        resnet_eps: float = 1e-6,
+        resnet_time_scale_shift: str = "default",
+        resnet_act_fn: str = "swish",
+        resnet_groups: int = 32,
+        resnet_pre_norm: bool = True,
+        output_scale_factor: float = 1.0,
+        add_downsample: bool = True,
+        downsample_stride: int = 2,
+        downsample_padding: int = 1,
+    ):
+        super().__init__()
+        resnets = []
+
+        for i in range(num_layers):
+            in_channels = in_channels if i == 0 else out_channels
+            resnets.append(
+                ResnetBlockCausal3D(
+                    in_channels=in_channels,
+                    out_channels=out_channels,
+                    temb_channels=None,
+                    eps=resnet_eps,
+                    groups=resnet_groups,
+                    dropout=dropout,
+                    time_embedding_norm=resnet_time_scale_shift,
+                    non_linearity=resnet_act_fn,
+                    output_scale_factor=output_scale_factor,
+                    pre_norm=resnet_pre_norm,
+                )
+            )
+
+        self.resnets = nn.ModuleList(resnets)
+
+        if add_downsample:
+            self.downsamplers = nn.ModuleList(
+                [
+                    DownsampleCausal3D(
+                        out_channels,
+                        use_conv=True,
+                        out_channels=out_channels,
+                        padding=downsample_padding,
+                        name="op",
+                        stride=downsample_stride,
+                    )
+                ]
+            )
+        else:
+            self.downsamplers = None
+
+    def forward(self, hidden_states: torch.FloatTensor, scale: float = 1.0) -> torch.FloatTensor:
+        for resnet in self.resnets:
+            hidden_states = resnet(hidden_states, temb=None, scale=scale)
+
+        if self.downsamplers is not None:
+            for downsampler in self.downsamplers:
+                hidden_states = downsampler(hidden_states, scale)
+
+        return hidden_states
+
+
+class UpDecoderBlockCausal3D(nn.Module):
+    def __init__(
+        self,
+        in_channels: int,
+        out_channels: int,
+        resolution_idx: Optional[int] = None,
+        dropout: float = 0.0,
+        num_layers: int = 1,
+        resnet_eps: float = 1e-6,
+        resnet_time_scale_shift: str = "default",  # default, spatial
+        resnet_act_fn: str = "swish",
+        resnet_groups: int = 32,
+        resnet_pre_norm: bool = True,
+        output_scale_factor: float = 1.0,
+        add_upsample: bool = True,
+        upsample_scale_factor=(2, 2, 2),
+        temb_channels: Optional[int] = None,
+    ):
+        super().__init__()
+        resnets = []
+
+        for i in range(num_layers):
+            input_channels = in_channels if i == 0 else out_channels
+
+            resnets.append(
+                ResnetBlockCausal3D(
+                    in_channels=input_channels,
+                    out_channels=out_channels,
+                    temb_channels=temb_channels,
+                    eps=resnet_eps,
+                    groups=resnet_groups,
+                    dropout=dropout,
+                    time_embedding_norm=resnet_time_scale_shift,
+                    non_linearity=resnet_act_fn,
+                    output_scale_factor=output_scale_factor,
+                    pre_norm=resnet_pre_norm,
+                )
+            )
+
+        self.resnets = nn.ModuleList(resnets)
+
+        if add_upsample:
+            self.upsamplers = nn.ModuleList(
+                [
+                    UpsampleCausal3D(
+                        out_channels,
+                        use_conv=True,
+                        out_channels=out_channels,
+                        upsample_factor=upsample_scale_factor,
+                    )
+                ]
+            )
+        else:
+            self.upsamplers = None
+
+        self.resolution_idx = resolution_idx
+
+    def forward(
+        self, hidden_states: torch.FloatTensor, temb: Optional[torch.FloatTensor] = None, scale: float = 1.0
+    ) -> torch.FloatTensor:
+        for resnet in self.resnets:
+            hidden_states = resnet(hidden_states, temb=temb, scale=scale)
+
+        if self.upsamplers is not None:
+            for upsampler in self.upsamplers:
+                hidden_states = upsampler(hidden_states)
+
+        return hidden_states

hyvideo/vae/vae.py

@@ -0,0 +1,355 @@
+from dataclasses import dataclass
+from typing import Optional, Tuple
+
+import numpy as np
+import torch
+import torch.nn as nn
+
+from diffusers.utils import BaseOutput, is_torch_version
+from diffusers.utils.torch_utils import randn_tensor
+from diffusers.models.attention_processor import SpatialNorm
+from .unet_causal_3d_blocks import (
+    CausalConv3d,
+    UNetMidBlockCausal3D,
+    get_down_block3d,
+    get_up_block3d,
+)
+
+
+@dataclass
+class DecoderOutput(BaseOutput):
+    r"""
+    Output of decoding method.
+
+    Args:
+        sample (`torch.FloatTensor` of shape `(batch_size, num_channels, height, width)`):
+            The decoded output sample from the last layer of the model.
+    """
+
+    sample: torch.FloatTensor
+
+
+class EncoderCausal3D(nn.Module):
+    r"""
+    The `EncoderCausal3D` layer of a variational autoencoder that encodes its input into a latent representation.
+    """
+
+    def __init__(
+        self,
+        in_channels: int = 3,
+        out_channels: int = 3,
+        down_block_types: Tuple[str, ...] = ("DownEncoderBlockCausal3D",),
+        block_out_channels: Tuple[int, ...] = (64,),
+        layers_per_block: int = 2,
+        norm_num_groups: int = 32,
+        act_fn: str = "silu",
+        double_z: bool = True,
+        mid_block_add_attention=True,
+        time_compression_ratio: int = 4,
+        spatial_compression_ratio: int = 8,
+    ):
+        super().__init__()
+        self.layers_per_block = layers_per_block
+
+        self.conv_in = CausalConv3d(in_channels, block_out_channels[0], kernel_size=3, stride=1)
+        self.mid_block = None
+        self.down_blocks = nn.ModuleList([])
+
+        # down
+        output_channel = block_out_channels[0]
+        for i, down_block_type in enumerate(down_block_types):
+            input_channel = output_channel
+            output_channel = block_out_channels[i]
+            is_final_block = i == len(block_out_channels) - 1
+            num_spatial_downsample_layers = int(np.log2(spatial_compression_ratio))
+            num_time_downsample_layers = int(np.log2(time_compression_ratio))
+
+            if time_compression_ratio == 4:
+                add_spatial_downsample = bool(i < num_spatial_downsample_layers)
+                add_time_downsample = bool(
+                    i >= (len(block_out_channels) - 1 - num_time_downsample_layers)
+                    and not is_final_block
+                )
+            else:
+                raise ValueError(f"Unsupported time_compression_ratio: {time_compression_ratio}.")
+
+            downsample_stride_HW = (2, 2) if add_spatial_downsample else (1, 1)
+            downsample_stride_T = (2,) if add_time_downsample else (1,)
+            downsample_stride = tuple(downsample_stride_T + downsample_stride_HW)
+            down_block = get_down_block3d(
+                down_block_type,
+                num_layers=self.layers_per_block,
+                in_channels=input_channel,
+                out_channels=output_channel,
+                add_downsample=bool(add_spatial_downsample or add_time_downsample),
+                downsample_stride=downsample_stride,
+                resnet_eps=1e-6,
+                downsample_padding=0,
+                resnet_act_fn=act_fn,
+                resnet_groups=norm_num_groups,
+                attention_head_dim=output_channel,
+                temb_channels=None,
+            )
+            self.down_blocks.append(down_block)
+
+        # mid
+        self.mid_block = UNetMidBlockCausal3D(
+            in_channels=block_out_channels[-1],
+            resnet_eps=1e-6,
+            resnet_act_fn=act_fn,
+            output_scale_factor=1,
+            resnet_time_scale_shift="default",
+            attention_head_dim=block_out_channels[-1],
+            resnet_groups=norm_num_groups,
+            temb_channels=None,
+            add_attention=mid_block_add_attention,
+        )
+
+        # out
+        self.conv_norm_out = nn.GroupNorm(num_channels=block_out_channels[-1], num_groups=norm_num_groups, eps=1e-6)
+        self.conv_act = nn.SiLU()
+
+        conv_out_channels = 2 * out_channels if double_z else out_channels
+        self.conv_out = CausalConv3d(block_out_channels[-1], conv_out_channels, kernel_size=3)
+
+    def forward(self, sample: torch.FloatTensor) -> torch.FloatTensor:
+        r"""The forward method of the `EncoderCausal3D` class."""
+        assert len(sample.shape) == 5, "The input tensor should have 5 dimensions"
+
+        sample = self.conv_in(sample)
+
+        # down
+        for down_block in self.down_blocks:
+            sample = down_block(sample)
+
+        # middle
+        sample = self.mid_block(sample)
+
+        # post-process
+        sample = self.conv_norm_out(sample)
+        sample = self.conv_act(sample)
+        sample = self.conv_out(sample)
+
+        return sample
+
+
+class DecoderCausal3D(nn.Module):
+    r"""
+    The `DecoderCausal3D` layer of a variational autoencoder that decodes its latent representation into an output sample.
+    """
+
+    def __init__(
+        self,
+        in_channels: int = 3,
+        out_channels: int = 3,
+        up_block_types: Tuple[str, ...] = ("UpDecoderBlockCausal3D",),
+        block_out_channels: Tuple[int, ...] = (64,),
+        layers_per_block: int = 2,
+        norm_num_groups: int = 32,
+        act_fn: str = "silu",
+        norm_type: str = "group",  # group, spatial
+        mid_block_add_attention=True,
+        time_compression_ratio: int = 4,
+        spatial_compression_ratio: int = 8,
+    ):
+        super().__init__()
+        self.layers_per_block = layers_per_block
+
+        self.conv_in = CausalConv3d(in_channels, block_out_channels[-1], kernel_size=3, stride=1)
+        self.mid_block = None
+        self.up_blocks = nn.ModuleList([])
+
+        temb_channels = in_channels if norm_type == "spatial" else None
+
+        # mid
+        self.mid_block = UNetMidBlockCausal3D(
+            in_channels=block_out_channels[-1],
+            resnet_eps=1e-6,
+            resnet_act_fn=act_fn,
+            output_scale_factor=1,
+            resnet_time_scale_shift="default" if norm_type == "group" else norm_type,
+            attention_head_dim=block_out_channels[-1],
+            resnet_groups=norm_num_groups,
+            temb_channels=temb_channels,
+            add_attention=mid_block_add_attention,
+        )
+
+        # up
+        reversed_block_out_channels = list(reversed(block_out_channels))
+        output_channel = reversed_block_out_channels[0]
+        for i, up_block_type in enumerate(up_block_types):
+            prev_output_channel = output_channel
+            output_channel = reversed_block_out_channels[i]
+            is_final_block = i == len(block_out_channels) - 1
+            num_spatial_upsample_layers = int(np.log2(spatial_compression_ratio))
+            num_time_upsample_layers = int(np.log2(time_compression_ratio))
+
+            if time_compression_ratio == 4:
+                add_spatial_upsample = bool(i < num_spatial_upsample_layers)
+                add_time_upsample = bool(
+                    i >= len(block_out_channels) - 1 - num_time_upsample_layers
+                    and not is_final_block
+                )
+            else:
+                raise ValueError(f"Unsupported time_compression_ratio: {time_compression_ratio}.")
+
+            upsample_scale_factor_HW = (2, 2) if add_spatial_upsample else (1, 1)
+            upsample_scale_factor_T = (2,) if add_time_upsample else (1,)
+            upsample_scale_factor = tuple(upsample_scale_factor_T + upsample_scale_factor_HW)
+            up_block = get_up_block3d(
+                up_block_type,
+                num_layers=self.layers_per_block + 1,
+                in_channels=prev_output_channel,
+                out_channels=output_channel,
+                prev_output_channel=None,
+                add_upsample=bool(add_spatial_upsample or add_time_upsample),
+                upsample_scale_factor=upsample_scale_factor,
+                resnet_eps=1e-6,
+                resnet_act_fn=act_fn,
+                resnet_groups=norm_num_groups,
+                attention_head_dim=output_channel,
+                temb_channels=temb_channels,
+                resnet_time_scale_shift=norm_type,
+            )
+            self.up_blocks.append(up_block)
+            prev_output_channel = output_channel
+
+        # out
+        if norm_type == "spatial":
+            self.conv_norm_out = SpatialNorm(block_out_channels[0], temb_channels)
+        else:
+            self.conv_norm_out = nn.GroupNorm(num_channels=block_out_channels[0], num_groups=norm_num_groups, eps=1e-6)
+        self.conv_act = nn.SiLU()
+        self.conv_out = CausalConv3d(block_out_channels[0], out_channels, kernel_size=3)
+
+        self.gradient_checkpointing = False
+
+    def forward(
+        self,
+        sample: torch.FloatTensor,
+        latent_embeds: Optional[torch.FloatTensor] = None,
+    ) -> torch.FloatTensor:
+        r"""The forward method of the `DecoderCausal3D` class."""
+        assert len(sample.shape) == 5, "The input tensor should have 5 dimensions."
+
+        sample = self.conv_in(sample)
+
+        upscale_dtype = next(iter(self.up_blocks.parameters())).dtype
+        if self.training and self.gradient_checkpointing:
+
+            def create_custom_forward(module):
+                def custom_forward(*inputs):
+                    return module(*inputs)
+
+                return custom_forward
+
+            if is_torch_version(">=", "1.11.0"):
+                # middle
+                sample = torch.utils.checkpoint.checkpoint(
+                    create_custom_forward(self.mid_block),
+                    sample,
+                    latent_embeds,
+                    use_reentrant=False,
+                )
+                sample = sample.to(upscale_dtype)
+
+                # up
+                for up_block in self.up_blocks:
+                    sample = torch.utils.checkpoint.checkpoint(
+                        create_custom_forward(up_block),
+                        sample,
+                        latent_embeds,
+                        use_reentrant=False,
+                    )
+            else:
+                # middle
+                sample = torch.utils.checkpoint.checkpoint(
+                    create_custom_forward(self.mid_block), sample, latent_embeds
+                )
+                sample = sample.to(upscale_dtype)
+
+                # up
+                for up_block in self.up_blocks:
+                    sample = torch.utils.checkpoint.checkpoint(create_custom_forward(up_block), sample, latent_embeds)
+        else:
+            # middle
+            sample = self.mid_block(sample, latent_embeds)
+            sample = sample.to(upscale_dtype)
+
+            # up
+            for up_block in self.up_blocks:
+                sample = up_block(sample, latent_embeds)
+
+        # post-process
+        if latent_embeds is None:
+            sample = self.conv_norm_out(sample)
+        else:
+            sample = self.conv_norm_out(sample, latent_embeds)
+        sample = self.conv_act(sample)
+        sample = self.conv_out(sample)
+
+        return sample
+
+
+class DiagonalGaussianDistribution(object):
+    def __init__(self, parameters: torch.Tensor, deterministic: bool = False):
+        if parameters.ndim == 3:
+            dim = 2  # (B, L, C)
+        elif parameters.ndim == 5 or parameters.ndim == 4:
+            dim = 1  # (B, C, T, H ,W) / (B, C, H, W)
+        else:
+            raise NotImplementedError
+        self.parameters = parameters
+        self.mean, self.logvar = torch.chunk(parameters, 2, dim=dim)
+        self.logvar = torch.clamp(self.logvar, -30.0, 20.0)
+        self.deterministic = deterministic
+        self.std = torch.exp(0.5 * self.logvar)
+        self.var = torch.exp(self.logvar)
+        if self.deterministic:
+            self.var = self.std = torch.zeros_like(
+                self.mean, device=self.parameters.device, dtype=self.parameters.dtype
+            )
+
+    def sample(self, generator: Optional[torch.Generator] = None) -> torch.FloatTensor:
+        # make sure sample is on the same device as the parameters and has same dtype
+        sample = randn_tensor(
+            self.mean.shape,
+            generator=generator,
+            device=self.parameters.device,
+            dtype=self.parameters.dtype,
+        )
+        x = self.mean + self.std * sample
+        return x
+
+    def kl(self, other: "DiagonalGaussianDistribution" = None) -> torch.Tensor:
+        if self.deterministic:
+            return torch.Tensor([0.0])
+        else:
+            reduce_dim = list(range(1, self.mean.ndim))
+            if other is None:
+                return 0.5 * torch.sum(
+                    torch.pow(self.mean, 2) + self.var - 1.0 - self.logvar,
+                    dim=reduce_dim,
+                )
+            else:
+                return 0.5 * torch.sum(
+                    torch.pow(self.mean - other.mean, 2) / other.var
+                    + self.var / other.var
+                    - 1.0
+                    - self.logvar
+                    + other.logvar,
+                    dim=reduce_dim,
+                )
+
+    def nll(self, sample: torch.Tensor, dims: Tuple[int, ...] = [1, 2, 3]) -> torch.Tensor:
+        if self.deterministic:
+            return torch.Tensor([0.0])
+        logtwopi = np.log(2.0 * np.pi)
+        return 0.5 * torch.sum(
+            logtwopi + self.logvar +
+            torch.pow(sample - self.mean, 2) / self.var,
+            dim=dims,
+        )
+
+    def mode(self) -> torch.Tensor:
+        return self.mean