import math from dataclasses import dataclass import torch from einops import rearrange, repeat from torch import Tensor, nn import torch.nn.functional as F import torch from einops import rearrange def attention(q, k, v, pe): q, k = apply_rope(q, k, pe) x = torch.nn.functional.scaled_dot_product_attention(q, k, v) x = rearrange(x, "B H L D -> B L (H D)") return x def rope(pos, dim: int, theta: int): assert dim % 2 == 0 scale = torch.arange(0, dim, 2, dtype=torch.float64, device=pos.device) / dim omega = 1.0 / (theta**scale) out = torch.einsum("...n,d->...nd", pos, omega) out = torch.stack([torch.cos(out), -torch.sin(out), torch.sin(out), torch.cos(out)], dim=-1) out = rearrange(out, "b n d (i j) -> b n d i j", i=2, j=2) return out.float() def apply_rope(xq, xk, freqs_cis): xq_ = xq.float().reshape(*xq.shape[:-1], -1, 1, 2) xk_ = xk.float().reshape(*xk.shape[:-1], -1, 1, 2) xq_out = freqs_cis[..., 0] * xq_[..., 0] + freqs_cis[..., 1] * xq_[..., 1] xk_out = freqs_cis[..., 0] * xk_[..., 0] + freqs_cis[..., 1] * xk_[..., 1] return xq_out.reshape(*xq.shape).type_as(xq), xk_out.reshape(*xk.shape).type_as(xk) class EmbedND(nn.Module): def __init__(self, dim: int, theta: int, axes_dim: list[int]): super().__init__() self.dim = dim self.theta = theta self.axes_dim = axes_dim def forward(self, ids: Tensor): n_axes = ids.shape[-1] emb = torch.cat( [rope(ids[..., i], self.axes_dim[i], self.theta) for i in range(n_axes)], dim=-3, ) return emb.unsqueeze(1) def timestep_embedding(t: Tensor, dim, max_period=10000, time_factor: float = 1000.0): """ Create sinusoidal timestep embeddings. :param t: a 1-D Tensor of N indices, one per batch element. These may be fractional. :param dim: the dimension of the output. :param max_period: controls the minimum frequency of the embeddings. :return: an (N, D) Tensor of positional embeddings. """ t = time_factor * t half = dim // 2 freqs = torch.exp(-math.log(max_period) * torch.arange(start=0, end=half, dtype=torch.float32) / half).to( 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) if torch.is_floating_point(t): embedding = embedding.to(t) return embedding class MLPEmbedder(nn.Module): def __init__(self, in_dim: int, hidden_dim: int): super().__init__() self.in_layer = nn.Linear(in_dim, hidden_dim, bias=True) self.silu = nn.SiLU() self.out_layer = nn.Linear(hidden_dim, hidden_dim, bias=True) def forward(self, x: Tensor): return self.out_layer(self.silu(self.in_layer(x))) class RMSNorm(torch.nn.Module): def __init__(self, dim: int): super().__init__() self.scale = nn.Parameter(torch.ones(dim)) def forward(self, x: Tensor): x_dtype = x.dtype x = x.float() rrms = torch.rsqrt(torch.mean(x**2, dim=-1, keepdim=True) + 1e-6) return (x * rrms).to(dtype=x_dtype) * self.scale class QKNorm(torch.nn.Module): def __init__(self, dim: int): super().__init__() self.query_norm = RMSNorm(dim) self.key_norm = RMSNorm(dim) def forward(self, q: Tensor, k: Tensor, v: Tensor): q = self.query_norm(q) k = self.key_norm(k) return q.to(v), k.to(v) class LoRALinearLayer(nn.Module): def __init__(self, in_features, out_features, rank=4, network_alpha=None, device=None, dtype=None): super().__init__() self.down = nn.Linear(in_features, rank, bias=False, device=device, dtype=dtype) self.up = nn.Linear(rank, out_features, bias=False, device=device, dtype=dtype) # This value has the same meaning as the `--network_alpha` option in the kohya-ss trainer script. # See https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning self.network_alpha = network_alpha self.rank = rank nn.init.normal_(self.down.weight, std=1 / rank) nn.init.zeros_(self.up.weight) def forward(self, hidden_states): orig_dtype = hidden_states.dtype dtype = self.down.weight.dtype down_hidden_states = self.down(hidden_states.to(dtype)) up_hidden_states = self.up(down_hidden_states) if self.network_alpha is not None: up_hidden_states *= self.network_alpha / self.rank return up_hidden_states.to(orig_dtype) class FLuxSelfAttnProcessor: def __call__(self, attn, x, pe, **attention_kwargs): print('2' * 30) qkv = attn.qkv(x) q, k, v = rearrange(qkv, "B L (K H D) -> K B H L D", K=3, H=self.num_heads) q, k = attn.norm(q, k, v) x = attention(q, k, v, pe=pe) x = attn.proj(x) return x class LoraFluxAttnProcessor(nn.Module): def __init__(self, dim: int, rank=4, network_alpha=None, lora_weight=1): super().__init__() self.qkv_lora = LoRALinearLayer(dim, dim * 3, rank, network_alpha) self.proj_lora = LoRALinearLayer(dim, dim, rank, network_alpha) self.lora_weight = lora_weight def __call__(self, attn, x, pe, **attention_kwargs): qkv = attn.qkv(x) + self.qkv_lora(x) * self.lora_weight q, k, v = rearrange(qkv, "B L (K H D) -> K B H L D", K=3, H=self.num_heads) q, k = attn.norm(q, k, v) x = attention(q, k, v, pe=pe) x = attn.proj(x) + self.proj_lora(x) * self.lora_weight print('1' * 30) print(x.norm(), (self.proj_lora(x) * self.lora_weight).norm(), 'norm') return x class SelfAttention(nn.Module): def __init__(self, dim: int, num_heads: int = 8, qkv_bias: bool = False): super().__init__() self.num_heads = num_heads head_dim = dim // num_heads self.qkv = nn.Linear(dim, dim * 3, bias=qkv_bias) self.norm = QKNorm(head_dim) self.proj = nn.Linear(dim, dim) def forward(): pass @dataclass class ModulationOut: shift: Tensor scale: Tensor gate: Tensor class Modulation(nn.Module): def __init__(self, dim: int, double: bool): super().__init__() self.is_double = double self.multiplier = 6 if double else 3 self.lin = nn.Linear(dim, self.multiplier * dim, bias=True) def forward(self, vec: Tensor): out = self.lin(nn.functional.silu(vec))[:, None, :].chunk(self.multiplier, dim=-1) return ( ModulationOut(*out[:3]), ModulationOut(*out[3:]) if self.is_double else None, ) class DoubleStreamBlockLoraProcessor(nn.Module): def __init__(self, dim: int, rank=4, network_alpha=None, lora_weight=1): super().__init__() self.qkv_lora1 = LoRALinearLayer(dim, dim * 3, rank, network_alpha) self.proj_lora1 = LoRALinearLayer(dim, dim, rank, network_alpha) self.qkv_lora2 = LoRALinearLayer(dim, dim * 3, rank, network_alpha) self.proj_lora2 = LoRALinearLayer(dim, dim, rank, network_alpha) self.lora_weight = lora_weight def __call__(self, attn, img, txt, vec, pe): img_mod1, img_mod2 = attn.img_mod(vec) txt_mod1, txt_mod2 = attn.txt_mod(vec) # prepare image for attention img_modulated = attn.img_norm1(img) img_modulated = (1 + img_mod1.scale) * img_modulated + img_mod1.shift img_qkv = attn.img_attn.qkv(img_modulated) + self.qkv_lora1(img_modulated) * self.lora_weight img_q, img_k, img_v = rearrange(img_qkv, "B L (K H D) -> K B H L D", K=3, H=attn.num_heads) img_q, img_k = attn.img_attn.norm(img_q, img_k, img_v) # prepare txt for attention txt_modulated = attn.txt_norm1(txt) txt_modulated = (1 + txt_mod1.scale) * txt_modulated + txt_mod1.shift txt_qkv = attn.txt_attn.qkv(txt_modulated) + self.qkv_lora2(txt_modulated) * self.lora_weight txt_q, txt_k, txt_v = rearrange(txt_qkv, "B L (K H D) -> K B H L D", K=3, H=attn.num_heads) txt_q, txt_k = attn.txt_attn.norm(txt_q, txt_k, txt_v) # run actual attention q = torch.cat((txt_q, img_q), dim=2) k = torch.cat((txt_k, img_k), dim=2) v = torch.cat((txt_v, img_v), dim=2) attn1 = attention(q, k, v, pe=pe) txt_attn, img_attn = attn1[:, : txt.shape[1]], attn1[:, txt.shape[1] :] # calculate the img bloks img = img + img_mod1.gate * attn.img_attn.proj(img_attn) + img_mod1.gate * self.proj_lora1(img_attn) * self.lora_weight img = img + img_mod2.gate * attn.img_mlp((1 + img_mod2.scale) * attn.img_norm2(img) + img_mod2.shift) # calculate the txt bloks txt = txt + txt_mod1.gate * attn.txt_attn.proj(txt_attn) + txt_mod1.gate * self.proj_lora2(txt_attn) * self.lora_weight txt = txt + txt_mod2.gate * attn.txt_mlp((1 + txt_mod2.scale) * attn.txt_norm2(txt) + txt_mod2.shift) return img, txt class IPDoubleStreamBlockProcessor(nn.Module): """Attention processor for handling IP-adapter with double stream block.""" def __init__(self, context_dim, hidden_dim): super().__init__() if not hasattr(F, "scaled_dot_product_attention"): raise ImportError( "IPDoubleStreamBlockProcessor requires PyTorch 2.0 or higher. Please upgrade PyTorch." ) # Ensure context_dim matches the dimension of image_proj self.context_dim = context_dim self.hidden_dim = hidden_dim # Initialize projections for IP-adapter self.ip_adapter_double_stream_k_proj = nn.Linear(context_dim, hidden_dim, bias=True) self.ip_adapter_double_stream_v_proj = nn.Linear(context_dim, hidden_dim, bias=True) nn.init.zeros_(self.ip_adapter_double_stream_k_proj.weight) nn.init.zeros_(self.ip_adapter_double_stream_k_proj.bias) nn.init.zeros_(self.ip_adapter_double_stream_v_proj.weight) nn.init.zeros_(self.ip_adapter_double_stream_v_proj.bias) def __call__(self, attn, img, txt, vec, pe, image_proj, ip_scale=1.0, **attention_kwargs): # Prepare image for attention img_mod1, img_mod2 = attn.img_mod(vec) txt_mod1, txt_mod2 = attn.txt_mod(vec) img_modulated = attn.img_norm1(img) img_modulated = (1 + img_mod1.scale) * img_modulated + img_mod1.shift img_qkv = attn.img_attn.qkv(img_modulated) img_q, img_k, img_v = rearrange(img_qkv, "B L (K H D) -> K B H L D", K=3, H=attn.num_heads, D=attn.head_dim) img_q, img_k = attn.img_attn.norm(img_q, img_k, img_v) txt_modulated = attn.txt_norm1(txt) txt_modulated = (1 + txt_mod1.scale) * txt_modulated + txt_mod1.shift txt_qkv = attn.txt_attn.qkv(txt_modulated) txt_q, txt_k, txt_v = rearrange(txt_qkv, "B L (K H D) -> K B H L D", K=3, H=attn.num_heads, D=attn.head_dim) txt_q, txt_k = attn.txt_attn.norm(txt_q, txt_k, txt_v) q = torch.cat((txt_q, img_q), dim=2) k = torch.cat((txt_k, img_k), dim=2) v = torch.cat((txt_v, img_v), dim=2) attn1 = attention(q, k, v, pe=pe) txt_attn, img_attn = attn1[:, :txt.shape[1]], attn1[:, txt.shape[1]:] img = img + img_mod1.gate * attn.img_attn.proj(img_attn) img = img + img_mod2.gate * attn.img_mlp((1 + img_mod2.scale) * attn.img_norm2(img) + img_mod2.shift) txt = txt + txt_mod1.gate * attn.txt_attn.proj(txt_attn) txt = txt + txt_mod2.gate * attn.txt_mlp((1 + txt_mod2.scale) * attn.txt_norm2(txt) + txt_mod2.shift) # IP-adapter processing ip_query = img_q # latent sample query ip_key = self.ip_adapter_double_stream_k_proj(image_proj) ip_value = self.ip_adapter_double_stream_v_proj(image_proj) # Reshape projections for multi-head attention ip_key = rearrange(ip_key, 'B L (H D) -> B H L D', H=attn.num_heads, D=attn.head_dim) ip_value = rearrange(ip_value, 'B L (H D) -> B H L D', H=attn.num_heads, D=attn.head_dim) # Compute attention between IP projections and the latent query ip_attention = F.scaled_dot_product_attention( ip_query, ip_key, ip_value, dropout_p=0.0, is_causal=False ) ip_attention = rearrange(ip_attention, "B H L D -> B L (H D)", H=attn.num_heads, D=attn.head_dim) img = img + ip_scale * ip_attention return img, txt class DoubleStreamBlockProcessor: def __call__(self, attn, img, txt, vec, pe): img_mod1, img_mod2 = attn.img_mod(vec) txt_mod1, txt_mod2 = attn.txt_mod(vec) # prepare image for attention img_modulated = attn.img_norm1(img) img_modulated = (1 + img_mod1.scale) * img_modulated + img_mod1.shift img_qkv = attn.img_attn.qkv(img_modulated) img_q, img_k, img_v = rearrange(img_qkv, "B L (K H D) -> K B H L D", K=3, H=attn.num_heads, D=attn.head_dim) img_q, img_k = attn.img_attn.norm(img_q, img_k, img_v) # prepare txt for attention txt_modulated = attn.txt_norm1(txt) txt_modulated = (1 + txt_mod1.scale) * txt_modulated + txt_mod1.shift txt_qkv = attn.txt_attn.qkv(txt_modulated) txt_q, txt_k, txt_v = rearrange(txt_qkv, "B L (K H D) -> K B H L D", K=3, H=attn.num_heads, D=attn.head_dim) txt_q, txt_k = attn.txt_attn.norm(txt_q, txt_k, txt_v) # run actual attention q = torch.cat((txt_q, img_q), dim=2) k = torch.cat((txt_k, img_k), dim=2) v = torch.cat((txt_v, img_v), dim=2) attn1 = attention(q, k, v, pe=pe) txt_attn, img_attn = attn1[:, : txt.shape[1]], attn1[:, txt.shape[1] :] # calculate the img bloks img = img + img_mod1.gate * attn.img_attn.proj(img_attn) img = img + img_mod2.gate * attn.img_mlp((1 + img_mod2.scale) * attn.img_norm2(img) + img_mod2.shift) # calculate the txt bloks txt = txt + txt_mod1.gate * attn.txt_attn.proj(txt_attn) txt = txt + txt_mod2.gate * attn.txt_mlp((1 + txt_mod2.scale) * attn.txt_norm2(txt) + txt_mod2.shift) return img, txt class DoubleStreamBlock(nn.Module): def __init__(self, hidden_size: int, num_heads: int, mlp_ratio: float, qkv_bias: bool = False): super().__init__() mlp_hidden_dim = int(hidden_size * mlp_ratio) self.num_heads = num_heads self.hidden_size = hidden_size self.head_dim = hidden_size // num_heads self.img_mod = Modulation(hidden_size, double=True) self.img_norm1 = nn.LayerNorm(hidden_size, elementwise_affine=False, eps=1e-6) self.img_attn = SelfAttention(dim=hidden_size, num_heads=num_heads, qkv_bias=qkv_bias) self.img_norm2 = nn.LayerNorm(hidden_size, elementwise_affine=False, eps=1e-6) self.img_mlp = nn.Sequential( nn.Linear(hidden_size, mlp_hidden_dim, bias=True), nn.GELU(approximate="tanh"), nn.Linear(mlp_hidden_dim, hidden_size, bias=True), ) self.txt_mod = Modulation(hidden_size, double=True) self.txt_norm1 = nn.LayerNorm(hidden_size, elementwise_affine=False, eps=1e-6) self.txt_attn = SelfAttention(dim=hidden_size, num_heads=num_heads, qkv_bias=qkv_bias) self.txt_norm2 = nn.LayerNorm(hidden_size, elementwise_affine=False, eps=1e-6) self.txt_mlp = nn.Sequential( nn.Linear(hidden_size, mlp_hidden_dim, bias=True), nn.GELU(approximate="tanh"), nn.Linear(mlp_hidden_dim, hidden_size, bias=True), ) processor = DoubleStreamBlockProcessor() self.set_processor(processor) def set_processor(self, processor): self.processor = processor def get_processor(self): return self.processor def forward( self, img: Tensor, txt: Tensor, vec: Tensor, pe: Tensor, image_proj: Tensor = None, ip_scale: float =1.0, ): if image_proj is None: return self.processor(self, img, txt, vec, pe) else: return self.processor(self, img, txt, vec, pe, image_proj, ip_scale) class IPSingleStreamBlockProcessor(nn.Module): """Attention processor for handling IP-adapter with single stream block.""" def __init__(self, context_dim, hidden_dim): super().__init__() if not hasattr(F, "scaled_dot_product_attention"): raise ImportError( "IPSingleStreamBlockProcessor requires PyTorch 2.0 or higher. Please upgrade PyTorch." ) # Ensure context_dim matches the dimension of image_proj self.context_dim = context_dim self.hidden_dim = hidden_dim # Initialize projections for IP-adapter self.ip_adapter_single_stream_k_proj = nn.Linear(context_dim, hidden_dim, bias=False) self.ip_adapter_single_stream_v_proj = nn.Linear(context_dim, hidden_dim, bias=False) nn.init.zeros_(self.ip_adapter_single_stream_k_proj.weight) nn.init.zeros_(self.ip_adapter_single_stream_v_proj.weight) def __call__( self, attn: nn.Module, x: Tensor, vec: Tensor, pe: Tensor, image_proj: Tensor = None, ip_scale: float = 1.0 ): mod, _ = attn.modulation(vec) x_mod = (1 + mod.scale) * attn.pre_norm(x) + mod.shift qkv, mlp = torch.split(attn.linear1(x_mod), [3 * attn.hidden_size, attn.mlp_hidden_dim], dim=-1) q, k, v = rearrange(qkv, "B L (K H D) -> K B H L D", K=3, H=attn.num_heads, D=attn.head_dim) q, k = attn.norm(q, k, v) # compute attention attn_1 = attention(q, k, v, pe=pe) # IP-adapter processing ip_query = q ip_key = self.ip_adapter_single_stream_k_proj(image_proj) ip_value = self.ip_adapter_single_stream_v_proj(image_proj) # Reshape projections for multi-head attention ip_key = rearrange(ip_key, 'B L (H D) -> B H L D', H=attn.num_heads, D=attn.head_dim) ip_value = rearrange(ip_value, 'B L (H D) -> B H L D', H=attn.num_heads, D=attn.head_dim) # Compute attention between IP projections and the latent query ip_attention = F.scaled_dot_product_attention( ip_query, ip_key, ip_value ) ip_attention = rearrange(ip_attention, "B H L D -> B L (H D)") attn_out = attn_1 + ip_scale * ip_attention # compute activation in mlp stream, cat again and run second linear layer output = attn.linear2(torch.cat((attn_out, attn.mlp_act(mlp)), 2)) out = x + mod.gate * output return out class SingleStreamBlockLoraProcessor(nn.Module): def __init__(self, dim: int, rank: int = 4, network_alpha = None, lora_weight: float = 1): super().__init__() self.qkv_lora = LoRALinearLayer(dim, dim * 3, rank, network_alpha) self.proj_lora = LoRALinearLayer(dim, dim, rank, network_alpha) self.lora_weight = lora_weight def __call__(self, attn: nn.Module, x: Tensor, vec: Tensor, pe: Tensor): mod, _ = attn.modulation(vec) x_mod = (1 + mod.scale) * attn.pre_norm(x) + mod.shift qkv, mlp = torch.split(attn.linear1(x_mod), [3 * attn.hidden_size, attn.mlp_hidden_dim], dim=-1) qkv = qkv + self.qkv_lora(x_mod) * self.lora_weight q, k, v = rearrange(qkv, "B L (K H D) -> K B H L D", K=3, H=attn.num_heads) q, k = attn.norm(q, k, v) # compute attention attn_1 = attention(q, k, v, pe=pe) # compute activation in mlp stream, cat again and run second linear layer output = attn.linear2(torch.cat((attn_1, attn.mlp_act(mlp)), 2)) output = output + self.proj_lora(output) * self.lora_weight output = x + mod.gate * output return output class SingleStreamBlockProcessor: def __call__(self, attn: nn.Module, x: Tensor, vec: Tensor, pe: Tensor): mod, _ = attn.modulation(vec) x_mod = (1 + mod.scale) * attn.pre_norm(x) + mod.shift qkv, mlp = torch.split(attn.linear1(x_mod), [3 * attn.hidden_size, attn.mlp_hidden_dim], dim=-1) q, k, v = rearrange(qkv, "B L (K H D) -> K B H L D", K=3, H=attn.num_heads) q, k = attn.norm(q, k, v) # compute attention attn_1 = attention(q, k, v, pe=pe) # compute activation in mlp stream, cat again and run second linear layer output = attn.linear2(torch.cat((attn_1, attn.mlp_act(mlp)), 2)) output = x + mod.gate * output return output class SingleStreamBlock(nn.Module): """ A DiT block with parallel linear layers as described in https://arxiv.org/abs/2302.05442 and adapted modulation interface. """ def __init__( self, hidden_size: int, num_heads: int, mlp_ratio: float = 4.0, qk_scale: float = None, ): super().__init__() self.hidden_dim = hidden_size self.num_heads = num_heads self.head_dim = hidden_size // num_heads self.scale = qk_scale or self.head_dim**-0.5 self.mlp_hidden_dim = int(hidden_size * mlp_ratio) # qkv and mlp_in self.linear1 = nn.Linear(hidden_size, hidden_size * 3 + self.mlp_hidden_dim) # proj and mlp_out self.linear2 = nn.Linear(hidden_size + self.mlp_hidden_dim, hidden_size) self.norm = QKNorm(self.head_dim) self.hidden_size = hidden_size self.pre_norm = nn.LayerNorm(hidden_size, elementwise_affine=False, eps=1e-6) self.mlp_act = nn.GELU(approximate="tanh") self.modulation = Modulation(hidden_size, double=False) processor = SingleStreamBlockProcessor() self.set_processor(processor) def set_processor(self, processor): self.processor = processor def get_processor(self): return self.processor def forward( self, x: Tensor, vec: Tensor, pe: Tensor, image_proj: Tensor = None, ip_scale: float = 1.0 ): if image_proj is None: return self.processor(self, x, vec, pe) else: return self.processor(self, x, vec, pe, image_proj, ip_scale) class LastLayer(nn.Module): def __init__(self, hidden_size: int, patch_size: int, out_channels: int): super().__init__() self.norm_final = nn.LayerNorm(hidden_size, elementwise_affine=False, eps=1e-6) self.linear = nn.Linear(hidden_size, patch_size * patch_size * out_channels, bias=True) self.adaLN_modulation = nn.Sequential(nn.SiLU(), nn.Linear(hidden_size, 2 * hidden_size, bias=True)) def forward(self, x: Tensor, vec: Tensor) -> Tensor: shift, scale = self.adaLN_modulation(vec).chunk(2, dim=1) x = (1 + scale[:, None, :]) * self.norm_final(x) + shift[:, None, :] x = self.linear(x) return x class ImageProjModel(torch.nn.Module): """Projection Model https://github.com/tencent-ailab/IP-Adapter/blob/main/ip_adapter/ip_adapter.py#L28 """ def __init__(self, cross_attention_dim=1024, clip_embeddings_dim=1024, clip_extra_context_tokens=4): super().__init__() self.generator = None self.cross_attention_dim = cross_attention_dim self.clip_extra_context_tokens = clip_extra_context_tokens self.proj = torch.nn.Linear(clip_embeddings_dim, self.clip_extra_context_tokens * cross_attention_dim) self.norm = torch.nn.LayerNorm(cross_attention_dim) def forward(self, image_embeds): embeds = image_embeds clip_extra_context_tokens = self.proj(embeds).reshape( -1, self.clip_extra_context_tokens, self.cross_attention_dim ) clip_extra_context_tokens = self.norm(clip_extra_context_tokens) return clip_extra_context_tokens