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, }, }