Files
2026-07-13 12:31:40 +08:00

583 lines
21 KiB
Python

import types
from typing import List, Optional
import os
import torch
from torch import nn
from utils.scheduler import SchedulerInterface, FlowMatchScheduler
from wan_5b.modules.tokenizers import HuggingfaceTokenizer
from wan_5b.modules.model import WanModel
from wan_5b.modules.vae2_2 import _video_vae
from wan_5b.modules.t5 import umt5_xxl
from wan_5b.modules.causal_model import CausalWanModel
class WanTextEncoder(torch.nn.Module):
def __init__(self) -> None:
super().__init__()
self.text_encoder = umt5_xxl(
encoder_only=True,
return_tokenizer=False,
dtype=torch.float32,
device=torch.device('cpu')
).eval().requires_grad_(False)
self.text_encoder.load_state_dict(
torch.load("wan_models/Wan2.2-TI2V-5B/models_t5_umt5-xxl-enc-bf16.pth",
map_location='cpu', weights_only=False)
)
# Move text encoder to GPU if available
if torch.cuda.is_available():
self.text_encoder = self.text_encoder.cuda()
self.tokenizer = HuggingfaceTokenizer(
name="wan_models/Wan2.2-TI2V-5B/google/umt5-xxl/", seq_len=512, clean='whitespace')
@property
def device(self):
# Assume we are always on GPU
return torch.cuda.current_device()
def forward(self, text_prompts: List[str]) -> dict:
ids, mask = self.tokenizer(
text_prompts, return_mask=True, add_special_tokens=True)
ids = ids.to(self.device)
mask = mask.to(self.device)
seq_lens = mask.gt(0).sum(dim=1).long()
context = self.text_encoder(ids, mask)
for u, v in zip(context, seq_lens):
u[v:] = 0.0 # set padding to 0.0
return {
"prompt_embeds": context
}
class WanVAEWrapper(torch.nn.Module):
def __init__(self):
super().__init__()
mean = [
-0.2289,
-0.0052,
-0.1323,
-0.2339,
-0.2799,
0.0174,
0.1838,
0.1557,
-0.1382,
0.0542,
0.2813,
0.0891,
0.1570,
-0.0098,
0.0375,
-0.1825,
-0.2246,
-0.1207,
-0.0698,
0.5109,
0.2665,
-0.2108,
-0.2158,
0.2502,
-0.2055,
-0.0322,
0.1109,
0.1567,
-0.0729,
0.0899,
-0.2799,
-0.1230,
-0.0313,
-0.1649,
0.0117,
0.0723,
-0.2839,
-0.2083,
-0.0520,
0.3748,
0.0152,
0.1957,
0.1433,
-0.2944,
0.3573,
-0.0548,
-0.1681,
-0.0667,
]
std = [
0.4765,
1.0364,
0.4514,
1.1677,
0.5313,
0.4990,
0.4818,
0.5013,
0.8158,
1.0344,
0.5894,
1.0901,
0.6885,
0.6165,
0.8454,
0.4978,
0.5759,
0.3523,
0.7135,
0.6804,
0.5833,
1.4146,
0.8986,
0.5659,
0.7069,
0.5338,
0.4889,
0.4917,
0.4069,
0.4999,
0.6866,
0.4093,
0.5709,
0.6065,
0.6415,
0.4944,
0.5726,
1.2042,
0.5458,
1.6887,
0.3971,
1.0600,
0.3943,
0.5537,
0.5444,
0.4089,
0.7468,
0.7744,
]
self.mean = torch.tensor(mean, dtype=torch.float32)
self.std = torch.tensor(std, dtype=torch.float32)
# init model
self.model = _video_vae(
pretrained_path="wan_models/Wan2.2-TI2V-5B/Wan2.2_VAE.pth",
).eval().requires_grad_(False)
def encode_to_latent(self, pixel: torch.Tensor) -> torch.Tensor:
# pixel: [batch_size, num_channels, num_frames, height, width]
device, dtype = pixel.device, pixel.dtype
scale = [self.mean.to(device=device, dtype=dtype),
1.0 / self.std.to(device=device, dtype=dtype)]
output = [
self.model.encode(u.unsqueeze(0), scale).float().squeeze(0)
for u in pixel
]
output = torch.stack(output, dim=0)
# from [batch_size, num_channels, num_frames, height, width]
# to [batch_size, num_frames, num_channels, height, width]
output = output.permute(0, 2, 1, 3, 4)
return output
def decode_to_pixel(self, latent: torch.Tensor, use_cache: bool = False) -> torch.Tensor:
# from [batch_size, num_frames, num_channels, height, width]
# to [batch_size, num_channels, num_frames, height, width]
zs = latent.permute(0, 2, 1, 3, 4)
if use_cache:
assert latent.shape[0] == 1, "Batch size must be 1 when using cache"
device, dtype = latent.device, latent.dtype
scale = [self.mean.to(device=device, dtype=dtype),
1.0 / self.std.to(device=device, dtype=dtype)]
if use_cache:
decode_function = self.model.cached_decode
else:
decode_function = self.model.decode
output = []
for u in zs:
output.append(decode_function(u.unsqueeze(0), scale).float().clamp_(-1, 1).squeeze(0))
output = torch.stack(output, dim=0)
# from [batch_size, num_channels, num_frames, height, width]
# to [batch_size, num_frames, num_channels, height, width]
output = output.permute(0, 2, 1, 3, 4)
return output
def decode_to_pixel_chunk(self, latent: torch.Tensor, use_cache: bool = False, chunk_size: int = 1) -> torch.Tensor:
"""
Decode latent frames to pixel space.
Args:
latent: Latent tensor with shape [batch_size, num_frames, num_channels, height, width]
use_cache: Whether to use cached decoding (for streaming)
chunk_size: Number of latent frames to decode at once (default 240 to avoid OOM)
Returns:
Decoded video tensor with shape [batch_size, num_frames, num_channels, height, width]
"""
# latent shape: [batch_size, num_frames, num_channels, height, width]
# zs shape after permute: [batch_size, num_channels, num_frames, height, width]
zs = latent.permute(0, 2, 1, 3, 4)
if use_cache:
assert latent.shape[0] == 1, "Batch size must be 1 when using cache"
device, dtype = latent.device, latent.dtype
scale = [self.mean.to(device=device, dtype=dtype),
1.0 / self.std.to(device=device, dtype=dtype)]
if use_cache:
decode_function = self.model.cached_decode
else:
decode_function = self.model.decode
output = []
for u in zs:
num_frames = u.shape[1]
if num_frames <= chunk_size:
# Decode short clips in one pass.
if use_cache:
# Start this segment from a clean cache.
self.model.clear_cache()
decoded = decode_function(u.unsqueeze(0), scale).float().clamp_(-1, 1).squeeze(0)
decoded = decoded.cpu()
if use_cache:
# Clear after this segment so it cannot affect the next video.
self.model.clear_cache()
else:
# Decode longer clips in temporal chunks.
decoded_chunks = []
if use_cache:
# Clear once at the segment start; later chunks share the
# internal cache.
self.model.clear_cache()
for start_idx in range(0, num_frames, chunk_size):
end_idx = min(start_idx + chunk_size, num_frames)
chunk = u[:, start_idx:end_idx, :, :] # [C, chunk_frames, H, W]
decoded_chunk = decode_function(chunk.unsqueeze(0), scale).float().clamp_(-1, 1).squeeze(0)
decoded_chunks.append(decoded_chunk.cpu())
del decoded_chunk
torch.cuda.empty_cache()
decoded = torch.cat(decoded_chunks, dim=1)
if use_cache:
# Clear the cache after the full segment.
self.model.clear_cache()
output.append(decoded)
output = torch.stack(output, dim=0)
output = output.permute(0, 2, 1, 3, 4)
return output
class WanDiffusionWrapper(torch.nn.Module):
def __init__(
self,
model_name="Wan2.2-TI2V-5B",
timestep_shift=8.0,
is_causal=False,
local_attn_size=-1,
sink_size=0,
num_frame_per_block=1,
t_scale=1.0,
rope_method="linear",
original_seq_len=None,
):
super().__init__()
if is_causal:
self.model = CausalWanModel.from_pretrained(
f"wan_models/{model_name}/", local_attn_size=local_attn_size, sink_size=sink_size,
num_frame_per_block=num_frame_per_block)
else:
self.model = WanModel.from_pretrained(f"wan_models/{model_name}/")
self.model.eval()
self.model.t_scale = t_scale
self.model.rope_method = rope_method
self.model.original_seq_len = original_seq_len
# For non-causal diffusion, all frames share the same timestep
self.uniform_timestep = not is_causal
self.scheduler = FlowMatchScheduler(
shift=timestep_shift, sigma_min=0.0, extra_one_step=True
)
self.scheduler.set_timesteps(1000, training=True)
self.seq_len = 28160 # [1, 32, 48, 44, 80]
self.post_init()
self._compiled_model_call = None
def enable_gradient_checkpointing(self) -> None:
self.model.enable_gradient_checkpointing()
def configure_torch_compile(
self,
*,
backend: str = "inductor",
mode: str | None = "max-autotune-no-cudagraphs",
fullgraph: bool = False,
dynamic: bool | None = False,
options: dict | None = None,
suppress_errors: bool = True,
) -> bool:
from utils.torch_compile_utils import configure_module_call_torch_compile
self._compiled_model_call = configure_module_call_torch_compile(
self.model,
name="WanDiffusionWrapper5B.model",
backend=backend,
mode=mode,
fullgraph=fullgraph,
dynamic=dynamic,
options=options,
suppress_errors=suppress_errors,
)
return self._compiled_model_call is not None
def _call_model(self, *args, **kwargs):
# iter-39 v2: publish kv_cache scalars BEFORE entering the compiled
# graph. The earlier version (iter-39 v1) published them inside
# `_forward_inference`, but that function IS compiled, so each
# `.item()` triggered a graph break. Moving the reads to this eager
# wrapper keeps the dict lookups in the compiled attention forward
# free of `.item()` syncs without adding any graph break.
kv_cache = kwargs.get("kv_cache", None)
if kv_cache is not None and len(kv_cache) > 0:
try:
from wan_5b.modules.causal_model import _CURRENT_GRID_META
first_block_cache = kv_cache[0]
_CURRENT_GRID_META["global_end_index"] = int(
first_block_cache["global_end_index"].item()
)
_CURRENT_GRID_META["local_end_index"] = int(
first_block_cache["local_end_index"].item()
)
_ps = first_block_cache.get("pinned_start", None)
if _ps is not None and hasattr(_ps, "item"):
_CURRENT_GRID_META["pinned_start"] = int(_ps.item())
_CURRENT_GRID_META["pinned_len"] = int(
first_block_cache["pinned_len"].item()
)
else:
_CURRENT_GRID_META["pinned_start"] = -1
_CURRENT_GRID_META["pinned_len"] = 0
except (KeyError, AttributeError, ImportError):
pass
defer_kv_updates = (
os.environ.get("LLV2_DEFER_KV_UPDATES", "0") == "1"
and kv_cache is not None
)
if defer_kv_updates:
kwargs["defer_cache_updates"] = True
if self._compiled_model_call is not None:
# iter-25: signal cudagraph allocator that a new "step" starts.
# Required for mode=reduce-overhead when modules cache state
# (KV cache rolling buffers, fp4-quant scale tensors) so the
# cudagraph pool knows it can safely reuse step-N memory now
# that step-(N+1) is starting.
mark_step = getattr(torch.compiler, "cudagraph_mark_step_begin", None)
if mark_step is not None:
mark_step()
result = self._compiled_model_call(*args, **kwargs)
else:
result = self.model(*args, **kwargs)
if defer_kv_updates:
if not isinstance(result, tuple) or len(result) != 2:
raise RuntimeError(
"LLV2_DEFER_KV_UPDATES expected model to return "
"(output, cache_update_infos)."
)
output, cache_update_infos = result
if cache_update_infos:
self.model._apply_cache_updates(kv_cache, cache_update_infos)
return output
return result
def _convert_flow_pred_to_x0(self, flow_pred: torch.Tensor, xt: torch.Tensor, timestep: torch.Tensor) -> torch.Tensor:
"""
Convert flow matching's prediction to x0 prediction.
flow_pred: the prediction with shape [B, C, H, W]
xt: the input noisy data with shape [B, C, H, W]
timestep: the timestep with shape [B]
pred = noise - x0
x_t = (1-sigma_t) * x0 + sigma_t * noise
we have x0 = x_t - sigma_t * pred
see derivations https://chatgpt.com/share/67bf8589-3d04-8008-bc6e-4cf1a24e2d0e
"""
# use higher precision for calculations
original_dtype = flow_pred.dtype
flow_pred, xt, sigmas, timesteps = map(
lambda x: x.double().to(flow_pred.device), [flow_pred, xt,
self.scheduler.sigmas,
self.scheduler.timesteps]
)
timestep_id = torch.argmin(
(timesteps.unsqueeze(0) - timestep.unsqueeze(1)).abs(), dim=1)
sigma_t = sigmas[timestep_id].reshape(-1, 1, 1, 1)
x0_pred = xt - sigma_t * flow_pred
return x0_pred.to(original_dtype)
@staticmethod
def _convert_x0_to_flow_pred(scheduler, x0_pred: torch.Tensor, xt: torch.Tensor, timestep: torch.Tensor) -> torch.Tensor:
"""
Convert x0 prediction to flow matching's prediction.
x0_pred: the x0 prediction with shape [B, C, H, W]
xt: the input noisy data with shape [B, C, H, W]
timestep: the timestep with shape [B]
pred = (x_t - x_0) / sigma_t
"""
# use higher precision for calculations
original_dtype = x0_pred.dtype
x0_pred, xt, sigmas, timesteps = map(
lambda x: x.double().to(x0_pred.device), [x0_pred, xt,
scheduler.sigmas,
scheduler.timesteps]
)
timestep_id = torch.argmin(
(timesteps.unsqueeze(0) - timestep.unsqueeze(1)).abs(), dim=1)
sigma_t = sigmas[timestep_id].reshape(-1, 1, 1, 1)
flow_pred = (xt - x0_pred) / sigma_t
return flow_pred.to(original_dtype)
def forward(
self,
noisy_image_or_video: torch.Tensor, conditional_dict: dict,
timestep: torch.Tensor, kv_cache: Optional[List[dict]] = None,
crossattn_cache: Optional[List[dict]] = None,
current_start: Optional[int] = None,
classify_mode: Optional[bool] = False,
concat_time_embeddings: Optional[bool] = False,
clean_x: Optional[torch.Tensor] = None,
aug_t: Optional[torch.Tensor] = None,
cache_start: Optional[int] = None,
rope_temporal_offset: Optional[torch.Tensor] = None,
) -> torch.Tensor:
prompt_embeds = conditional_dict["prompt_embeds"]
# [B, F] -> [B]
if self.uniform_timestep:
input_timestep = timestep[:, 0]
else:
input_timestep = timestep
logits = None
rope_offset_was_set = (
rope_temporal_offset is not None
and hasattr(self.model, "rope_temporal_offset")
)
if rope_offset_was_set:
prev_rope_temporal_offset = self.model.rope_temporal_offset
self.model.rope_temporal_offset = rope_temporal_offset
# X0 prediction
if kv_cache is not None:
flow_pred = self._call_model(
noisy_image_or_video.permute(0, 2, 1, 3, 4),
t=input_timestep, context=prompt_embeds,
seq_len=self.seq_len,
kv_cache=kv_cache,
crossattn_cache=crossattn_cache,
current_start=current_start,
cache_start=cache_start
).permute(0, 2, 1, 3, 4)
else:
if clean_x is not None:
# teacher forcing
flow_pred = self._call_model(
noisy_image_or_video.permute(0, 2, 1, 3, 4),
t=input_timestep, context=prompt_embeds,
seq_len=self.seq_len,
clean_x=clean_x.permute(0, 2, 1, 3, 4),
aug_t=aug_t,
).permute(0, 2, 1, 3, 4)
else:
if classify_mode:
flow_pred, logits = self._call_model(
noisy_image_or_video.permute(0, 2, 1, 3, 4),
t=input_timestep, context=prompt_embeds,
seq_len=self.seq_len,
classify_mode=True,
register_tokens=self._register_tokens,
cls_pred_branch=self._cls_pred_branch,
gan_ca_blocks=self._gan_ca_blocks,
concat_time_embeddings=concat_time_embeddings
)
flow_pred = flow_pred.permute(0, 2, 1, 3, 4)
else:
flow_pred = self._call_model(
noisy_image_or_video.permute(0, 2, 1, 3, 4),
t=input_timestep, context=prompt_embeds,
seq_len=self.seq_len
).permute(0, 2, 1, 3, 4)
if rope_offset_was_set:
self.model.rope_temporal_offset = prev_rope_temporal_offset
pred_x0 = self._convert_flow_pred_to_x0(
flow_pred=flow_pred.flatten(0, 1),
xt=noisy_image_or_video.flatten(0, 1),
timestep=timestep.flatten(0, 1)
).unflatten(0, flow_pred.shape[:2])
if logits is not None:
return flow_pred, pred_x0, logits
return flow_pred, pred_x0
def get_scheduler(self) -> SchedulerInterface:
"""
Update the current scheduler with the interface's static method
"""
scheduler = self.scheduler
scheduler.convert_x0_to_noise = types.MethodType(
SchedulerInterface.convert_x0_to_noise, scheduler)
scheduler.convert_noise_to_x0 = types.MethodType(
SchedulerInterface.convert_noise_to_x0, scheduler)
scheduler.convert_velocity_to_x0 = types.MethodType(
SchedulerInterface.convert_velocity_to_x0, scheduler)
self.scheduler = scheduler
return scheduler
def post_init(self):
"""
A few custom initialization steps that should be called after the object is created.
Currently, the only one we have is to bind a few methods to scheduler.
We can gradually add more methods here if needed.
"""
self.get_scheduler()
_MG_LIGHTVAE_DEFAULT_PATHS = {
"mg_lightvae": os.path.join("wan_models", "Matrix-Game-3.0", "MG-LightVAE.pth"),
"mg_lightvae_v2": os.path.join("wan_models", "Matrix-Game-3.0", "MG-LightVAE_v2.pth"),
}
def build_vae_5b(args):
"""Return the 5B VAE wrapper requested by args.vae_type."""
vae_type = str(getattr(args, "vae_type", "wan")).lower().strip()
if vae_type in ("wan", "wan2.2", ""):
return WanVAEWrapper()
if vae_type in _MG_LIGHTVAE_DEFAULT_PATHS:
from utils.lightvae_5b_wrapper import LightVAE5BWrapper
return LightVAE5BWrapper(vae_path=_MG_LIGHTVAE_DEFAULT_PATHS[vae_type])
raise ValueError(
f"Unknown vae_type '{vae_type}'. "
"Expected one of: wan, mg_lightvae, mg_lightvae_v2."
)