ComfyUI/comfy/ldm/mage_flow/model.py

187 lines
8.7 KiB
Python

# Mage-Flow (https://github.com/microsoft/Mage) native-resolution MMDiT (MIT)
# Architecture is a 12-layer variant of the Qwen-Image double-stream block with
# patch_size=1 (no 2x2 packing), unrotated text tokens and a bf16-rounded
# timestep frequency table.
import math
import torch
import torch.nn as nn
from typing import Optional, Tuple
from comfy.ldm.lightricks.model import TimestepEmbedding
from comfy.ldm.flux.layers import EmbedND
from comfy.ldm.qwen_image.model import QwenImageTransformerBlock, LastLayer
import comfy.patcher_extension
class MageTimestepProjEmbeddings(nn.Module):
def __init__(self, embedding_dim, dtype=None, device=None, operations=None):
super().__init__()
self.timestep_embedder = TimestepEmbedding(
in_channels=256, time_embed_dim=embedding_dim,
dtype=dtype, device=device, operations=operations
)
def forward(self, timestep, hidden_states):
half_dim = 128
exponent = -math.log(10000) * torch.arange(half_dim, dtype=torch.float32, device=timestep.device) / half_dim
emb = torch.exp(exponent).to(timestep.dtype)
emb = timestep[:, None].float() * emb[None, :]
emb = 1000.0 * emb
emb = torch.cat([torch.sin(emb), torch.cos(emb)], dim=-1)
emb = torch.cat([emb[:, half_dim:], emb[:, :half_dim]], dim=-1) # flip_sin_to_cos
return self.timestep_embedder(emb.to(dtype=hidden_states.dtype))
class MageFlowTransformer2DModel(nn.Module):
def __init__(
self,
in_channels: int = 128,
out_channels: Optional[int] = 128,
num_layers: int = 12,
attention_head_dim: int = 128,
num_attention_heads: int = 24,
joint_attention_dim: int = 2560,
axes_dims_rope: Tuple[int, int, int] = (16, 56, 56),
image_model=None,
dtype=None,
device=None,
operations=None,
):
super().__init__()
self.dtype = dtype
self.patch_size = 1
self.in_channels = in_channels
self.out_channels = out_channels or in_channels
self.inner_dim = num_attention_heads * attention_head_dim
self.pe_embedder = EmbedND(dim=attention_head_dim, theta=10000, axes_dim=list(axes_dims_rope))
self.time_text_embed = MageTimestepProjEmbeddings(embedding_dim=self.inner_dim, dtype=dtype, device=device, operations=operations)
self.txt_norm = operations.RMSNorm(joint_attention_dim, eps=1e-6, dtype=dtype, device=device)
self.img_in = operations.Linear(in_channels, self.inner_dim, dtype=dtype, device=device)
self.txt_in = operations.Linear(joint_attention_dim, self.inner_dim, dtype=dtype, device=device)
self.transformer_blocks = nn.ModuleList([
QwenImageTransformerBlock(
dim=self.inner_dim,
num_attention_heads=num_attention_heads,
attention_head_dim=attention_head_dim,
dtype=dtype,
device=device,
operations=operations
)
for _ in range(num_layers)
])
self.norm_out = LastLayer(self.inner_dim, self.inner_dim, dtype=dtype, device=device, operations=operations)
self.proj_out = operations.Linear(self.inner_dim, self.out_channels, bias=True, dtype=dtype, device=device)
def process_img(self, x, index=0):
# patch_size=1: tokens are raw latent pixels, no 2x2 packing.
bs, c, h, w = x.shape
hidden_states = x.movedim(1, -1).reshape(bs, h * w, c)
img_ids = torch.zeros((h, w, 3), device=x.device)
# Frame axis: positive image index (0 = target, 1..N = reference images).
img_ids[:, :, 0] = index
# Mage scale_rope centering: positions [-ceil(n/2), floor(n/2)), i.e.
# offset by (n - n//2). Differs from Qwen-Image's -(n//2) for odd sizes.
img_ids[:, :, 1] = img_ids[:, :, 1] + torch.arange(h, device=x.device)[:, None] - (h - h // 2)
img_ids[:, :, 2] = img_ids[:, :, 2] + torch.arange(w, device=x.device)[None, :] - (w - w // 2)
return hidden_states, img_ids.reshape(h * w, 3).unsqueeze(0).expand(bs, -1, -1), (h, w)
def forward(self, x, timestep, context, attention_mask=None, ref_latents=None, transformer_options={}, **kwargs):
return comfy.patcher_extension.WrapperExecutor.new_class_executor(
self._forward,
self,
comfy.patcher_extension.get_all_wrappers(comfy.patcher_extension.WrappersMP.DIFFUSION_MODEL, transformer_options)
).execute(x, timestep, context, attention_mask, ref_latents, transformer_options, **kwargs)
def _forward(self, x, timestep, context, attention_mask=None, ref_latents=None, transformer_options={}, control=None, **kwargs):
if attention_mask is not None and not torch.is_floating_point(attention_mask):
attention_mask = (attention_mask - 1).to(x.dtype) * torch.finfo(x.dtype).max
hidden_states, img_ids, orig_shape = self.process_img(x)
num_embeds = hidden_states.shape[1]
if ref_latents is not None:
ref_num_tokens = []
index = 0
for ref in ref_latents:
index += 1
kontext, kontext_ids, _ = self.process_img(ref, index=index)
hidden_states = torch.cat([hidden_states, kontext], dim=1)
img_ids = torch.cat([img_ids, kontext_ids], dim=1)
ref_num_tokens.append(kontext.shape[1])
transformer_options = transformer_options.copy()
transformer_options["reference_image_num_tokens"] = ref_num_tokens
# Text tokens are not rotated in Mage-Flow: RoPE at position 0 is the
# identity rotation.
txt_ids = torch.zeros((x.shape[0], context.shape[1], 3), device=x.device)
hidden_states = self.img_in(hidden_states)
context = self.txt_norm(context)
context = self.txt_in(context)
temb = self.time_text_embed(timestep, hidden_states)
patches_replace = transformer_options.get("patches_replace", {})
patches = transformer_options.get("patches", {})
blocks_replace = patches_replace.get("dit", {})
if "post_input" in patches:
for p in patches["post_input"]:
out = p({"img": hidden_states, "txt": context, "img_ids": img_ids, "txt_ids": txt_ids, "transformer_options": transformer_options})
hidden_states = out["img"]
context = out["txt"]
img_ids = out["img_ids"]
txt_ids = out["txt_ids"]
ids = torch.cat((txt_ids, img_ids), dim=1)
image_rotary_emb = self.pe_embedder(ids).contiguous()
del ids, txt_ids, img_ids
transformer_options["total_blocks"] = len(self.transformer_blocks)
transformer_options["block_type"] = "double"
for i, block in enumerate(self.transformer_blocks):
transformer_options["block_index"] = i
if ("double_block", i) in blocks_replace:
def block_wrap(args):
out = {}
out["txt"], out["img"] = block(hidden_states=args["img"], encoder_hidden_states=args["txt"], encoder_hidden_states_mask=attention_mask, temb=args["vec"], image_rotary_emb=args["pe"], transformer_options=args["transformer_options"])
return out
out = blocks_replace[("double_block", i)]({"img": hidden_states, "txt": context, "vec": temb, "pe": image_rotary_emb, "transformer_options": transformer_options}, {"original_block": block_wrap})
hidden_states = out["img"]
context = out["txt"]
else:
context, hidden_states = block(
hidden_states=hidden_states,
encoder_hidden_states=context,
encoder_hidden_states_mask=attention_mask,
temb=temb,
image_rotary_emb=image_rotary_emb,
transformer_options=transformer_options,
)
if "double_block" in patches:
for p in patches["double_block"]:
out = p({"img": hidden_states, "txt": context, "x": x, "block_index": i, "transformer_options": transformer_options})
hidden_states = out["img"]
context = out["txt"]
if control is not None: # Controlnet
control_i = control.get("input")
if i < len(control_i):
add = control_i[i]
if add is not None:
hidden_states[:, :add.shape[1]] += add
hidden_states = self.norm_out(hidden_states, temb)
hidden_states = self.proj_out(hidden_states)
hidden_states = hidden_states[:, :num_embeds]
h, w = orig_shape
return hidden_states.reshape(x.shape[0], h, w, self.out_channels).movedim(-1, 1)