Add FlashVSR support: diffusion-based 4x video super-resolution (Wan 2.1-1.3B)

Vendor minimal diffsynth subset for FlashVSR inference (full/tiny pipelines,
v1 and v1.1 checkpoints auto-downloaded from HuggingFace). Includes segment-based
processing with temporal overlap and crossfade blending for bounded RAM on long videos.

Nodes: Load FlashVSR Model, FlashVSR Upscale, FlashVSR Segment Upscale.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

flashvsr_arch/models/TCDecoder.py

@@ -0,0 +1,320 @@
+#!/usr/bin/env python3
+"""
+Tiny AutoEncoder for Hunyuan Video (Decoder-only, pruned)
+- Encoder removed
+- Transplant/widening helpers removed
+- Deepening (IdentityConv2d+ReLU) is now built into the decoder structure itself
+"""
+
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+from tqdm.auto import tqdm
+from collections import namedtuple
+from einops import rearrange
+import torch.nn.init as init
+
+DecoderResult = namedtuple("DecoderResult", ("frame", "memory"))
+TWorkItem = namedtuple("TWorkItem", ("input_tensor", "block_index"))
+
+# ----------------------------
+# Utility / building blocks
+# ----------------------------
+
+class IdentityConv2d(nn.Conv2d):
+    """Same-shape Conv2d initialized to identity (Dirac)."""
+    def __init__(self, C, kernel_size=3, bias=False):
+        pad = kernel_size // 2
+        super().__init__(C, C, kernel_size, padding=pad, bias=bias)
+        with torch.no_grad():
+            init.dirac_(self.weight)
+            if self.bias is not None:
+                self.bias.zero_()
+
+def conv(n_in, n_out, **kwargs):
+    return nn.Conv2d(n_in, n_out, 3, padding=1, **kwargs)
+
+class Clamp(nn.Module):
+    def forward(self, x):
+        return torch.tanh(x / 3) * 3
+
+class MemBlock(nn.Module):
+    def __init__(self, n_in, n_out):
+        super().__init__()
+        self.conv = nn.Sequential(
+            conv(n_in * 2, n_out), nn.ReLU(inplace=True),
+            conv(n_out, n_out), nn.ReLU(inplace=True),
+            conv(n_out, n_out)
+        )
+        self.skip = nn.Conv2d(n_in, n_out, 1, bias=False) if n_in != n_out else nn.Identity()
+        self.act = nn.ReLU(inplace=True)
+    def forward(self, x, past):
+        return self.act(self.conv(torch.cat([x, past], 1)) + self.skip(x))
+
+class TPool(nn.Module):
+    def __init__(self, n_f, stride):
+        super().__init__()
+        self.stride = stride
+        self.conv = nn.Conv2d(n_f*stride, n_f, 1, bias=False)
+    def forward(self, x):
+        _NT, C, H, W = x.shape
+        return self.conv(x.reshape(-1, self.stride * C, H, W))
+
+class TGrow(nn.Module):
+    def __init__(self, n_f, stride):
+        super().__init__()
+        self.stride = stride
+        self.conv = nn.Conv2d(n_f, n_f*stride, 1, bias=False)
+    def forward(self, x):
+        _NT, C, H, W = x.shape
+        x = self.conv(x)
+        return x.reshape(-1, C, H, W)
+
+class PixelShuffle3d(nn.Module):
+    def __init__(self, ff, hh, ww):
+        super().__init__()
+        self.ff = ff
+        self.hh = hh
+        self.ww = ww
+    def forward(self, x):
+        # x: (B, C, F, H, W)
+        B, C, F, H, W = x.shape
+        if F % self.ff != 0:
+            first_frame = x[:, :, 0:1, :, :].repeat(1, 1, self.ff - F % self.ff, 1, 1)
+            x = torch.cat([first_frame, x], dim=2)
+        return rearrange(
+            x,
+            'b c (f ff) (h hh) (w ww) -> b (c ff hh ww) f h w',
+            ff=self.ff, hh=self.hh, ww=self.ww
+        ).transpose(1, 2)
+
+# ----------------------------
+# Generic NTCHW graph executor (kept; used by decoder)
+# ----------------------------
+
+def apply_model_with_memblocks(model, x, parallel, show_progress_bar, mem=None):
+    """
+    Apply a sequential model with memblocks to the given input.
+    Args:
+    - model: nn.Sequential of blocks to apply
+    - x: input data, of dimensions NTCHW
+    - parallel: if True, parallelize over timesteps (fast but uses O(T) memory)
+        if False, each timestep will be processed sequentially (slow but uses O(1) memory)
+    - show_progress_bar: if True, enables tqdm progressbar display
+
+    Returns NTCHW tensor of output data.
+    """
+    assert x.ndim == 5, f"TAEHV operates on NTCHW tensors, but got {x.ndim}-dim tensor"
+    N, T, C, H, W = x.shape
+    if parallel:
+        x = x.reshape(N*T, C, H, W)
+        for b in tqdm(model, disable=not show_progress_bar):
+            if isinstance(b, MemBlock):
+                NT, C, H, W = x.shape
+                T = NT // N
+                _x = x.reshape(N, T, C, H, W)
+                mem = F.pad(_x, (0,0,0,0,0,0,1,0), value=0)[:,:T].reshape(x.shape)
+                x = b(x, mem)
+            else:
+                x = b(x)
+        NT, C, H, W = x.shape
+        T = NT // N
+        x = x.view(N, T, C, H, W)
+    else:
+        out = []
+        work_queue = [TWorkItem(xt, 0) for t, xt in enumerate(x.reshape(N, T * C, H, W).chunk(T, dim=1))]
+        progress_bar = tqdm(range(T), disable=not show_progress_bar)
+        while work_queue:
+            xt, i = work_queue.pop(0)
+            if i == 0:
+                progress_bar.update(1)
+            if i == len(model):
+                out.append(xt)
+            else:
+                b = model[i]
+                if isinstance(b, MemBlock):
+                    if mem[i] is None:
+                        xt_new = b(xt, xt * 0)
+                        mem[i] = xt
+                    else:
+                        xt_new = b(xt, mem[i])
+                        mem[i].copy_(xt)
+                    work_queue.insert(0, TWorkItem(xt_new, i+1))
+                elif isinstance(b, TPool):
+                    if mem[i] is None:
+                        mem[i] = []
+                    mem[i].append(xt)
+                    if len(mem[i]) > b.stride:
+                        raise ValueError("TPool internal state invalid.")
+                    elif len(mem[i]) == b.stride:
+                        N_, C_, H_, W_ = xt.shape
+                        xt = b(torch.cat(mem[i], 1).view(N_*b.stride, C_, H_, W_))
+                        mem[i] = []
+                        work_queue.insert(0, TWorkItem(xt, i+1))
+                elif isinstance(b, TGrow):
+                    xt = b(xt)
+                    NT, C_, H_, W_ = xt.shape
+                    for xt_next in reversed(xt.view(N, b.stride*C_, H_, W_).chunk(b.stride, 1)):
+                        work_queue.insert(0, TWorkItem(xt_next, i+1))
+                else:
+                    xt = b(xt)
+                    work_queue.insert(0, TWorkItem(xt, i+1))
+        progress_bar.close()
+        x = torch.stack(out, 1)
+    return x, mem
+
+# ----------------------------
+# Decoder-only TAEHV
+# ----------------------------
+
+class TAEHV(nn.Module):
+    image_channels = 3
+    def __init__(
+        self,
+        checkpoint_path="taehv.pth",
+        decoder_time_upscale=(True, True),
+        decoder_space_upscale=(True, True, True),
+        channels = [256, 128, 64, 64],
+        latent_channels = 16
+    ):
+        """Initialize TAEHV (decoder-only) with built-in deepening after every ReLU.
+        Deepening config: how_many_each=1, k=3 (fixed as requested).
+        """
+        super().__init__()
+        self.latent_channels = latent_channels
+        n_f = channels
+        self.frames_to_trim = 2**sum(decoder_time_upscale) - 1
+
+        # Build the decoder "skeleton"
+        base_decoder = nn.Sequential(
+            Clamp(), conv(self.latent_channels, n_f[0]), nn.ReLU(inplace=True),
+
+            MemBlock(n_f[0], n_f[0]), MemBlock(n_f[0], n_f[0]), MemBlock(n_f[0], n_f[0]),
+            nn.Upsample(scale_factor=2 if decoder_space_upscale[0] else 1),
+            TGrow(n_f[0], 1),
+            conv(n_f[0], n_f[1], bias=False),
+
+            MemBlock(n_f[1], n_f[1]), MemBlock(n_f[1], n_f[1]), MemBlock(n_f[1], n_f[1]),
+            nn.Upsample(scale_factor=2 if decoder_space_upscale[1] else 1),
+            TGrow(n_f[1], 2 if decoder_time_upscale[0] else 1),
+            conv(n_f[1], n_f[2], bias=False),
+
+            MemBlock(n_f[2], n_f[2]), MemBlock(n_f[2], n_f[2]), MemBlock(n_f[2], n_f[2]),
+            nn.Upsample(scale_factor=2 if decoder_space_upscale[2] else 1),
+            TGrow(n_f[2], 2 if decoder_time_upscale[1] else 1),
+            conv(n_f[2], n_f[3], bias=False),
+
+            nn.ReLU(inplace=True), conv(n_f[3], TAEHV.image_channels),
+        )
+
+        # Inline deepening: insert (IdentityConv2d(k=3) + ReLU) after every ReLU
+        self.decoder = self._apply_identity_deepen(base_decoder, how_many_each=1, k=3)
+
+        self.pixel_shuffle = PixelShuffle3d(4, 8, 8)
+
+        if checkpoint_path is not None:
+            missing_keys = self.load_state_dict(
+                self.patch_tgrow_layers(torch.load(checkpoint_path, map_location="cpu", weights_only=True)),
+                strict=False
+            )
+            print('missing_keys', missing_keys)
+
+        # Initialize decoder mem state
+        self.mem = [None] * len(self.decoder)
+
+    @staticmethod
+    def _apply_identity_deepen(decoder: nn.Sequential, how_many_each=1, k=3) -> nn.Sequential:
+        """Return a new Sequential where every nn.ReLU is followed by how_many_each*(IdentityConv2d(k)+ReLU)."""
+        new_layers = []
+        for b in decoder:
+            new_layers.append(b)
+            if isinstance(b, nn.ReLU):
+                # Deduce channel count from preceding layer
+                C = None
+                if len(new_layers) >= 2 and isinstance(new_layers[-2], nn.Conv2d):
+                    C = new_layers[-2].out_channels
+                elif len(new_layers) >= 2 and isinstance(new_layers[-2], MemBlock):
+                    C = new_layers[-2].conv[-1].out_channels
+                if C is not None:
+                    for _ in range(how_many_each):
+                        new_layers.append(IdentityConv2d(C, kernel_size=k, bias=False))
+                        new_layers.append(nn.ReLU(inplace=True))
+        return nn.Sequential(*new_layers)
+
+    def patch_tgrow_layers(self, sd):
+        """Patch TGrow layers to use a smaller kernel if needed (decoder-only)."""
+        new_sd = self.state_dict()
+        for i, layer in enumerate(self.decoder):
+            if isinstance(layer, TGrow):
+                key = f"decoder.{i}.conv.weight"
+                if key in sd and sd[key].shape[0] > new_sd[key].shape[0]:
+                    sd[key] = sd[key][-new_sd[key].shape[0]:]
+        return sd
+
+    def decode_video(self, x, parallel=True, show_progress_bar=False, cond=None):
+        """Decode a sequence of frames from latents.
+        x: NTCHW latent tensor; returns NTCHW RGB in ~[0, 1].
+        """
+        trim_flag = self.mem[-8] is None  # keeps original relative check
+
+        if cond is not None:
+            x = torch.cat([self.pixel_shuffle(cond), x], dim=2)
+
+        x, self.mem = apply_model_with_memblocks(self.decoder, x, parallel, show_progress_bar, mem=self.mem)
+
+        if trim_flag:
+            return x[:, self.frames_to_trim:]
+        return x
+
+    def forward(self, *args, **kwargs):
+        raise NotImplementedError("Decoder-only model: call decode_video(...) instead.")
+
+    def clean_mem(self):
+        self.mem = [None] * len(self.decoder)
+
+class DotDict(dict):
+    __getattr__ = dict.__getitem__
+    __setattr__ = dict.__setitem__
+
+class TAEW2_1DiffusersWrapper(nn.Module):
+    def __init__(self, pretrained_path=None, channels = [256, 128, 64, 64]):
+        super().__init__()
+        self.dtype = torch.bfloat16
+        self.device = "cuda"
+        self.taehv = TAEHV(pretrained_path, channels = channels).to(self.dtype)
+        self.temperal_downsample = [True, True, False]  # [sic]
+        self.config = DotDict(scaling_factor=1.0, latents_mean=torch.zeros(16), z_dim=16, latents_std=torch.ones(16))
+
+    def decode(self, latents, return_dict=None):
+        n, c, t, h, w = latents.shape
+        return (self.taehv.decode_video(latents.transpose(1, 2), parallel=False).transpose(1, 2).mul_(2).sub_(1),)
+
+    def stream_decode_with_cond(self, latents, tiled=False, cond=None):
+        n, c, t, h, w = latents.shape
+        return self.taehv.decode_video(latents.transpose(1, 2), parallel=False, cond=cond).transpose(1, 2).mul_(2).sub_(1)
+
+    def clean_mem(self):
+        self.taehv.clean_mem()
+
+# ----------------------------
+# Simplified builder (no small, no transplant, no post-hoc deepening)
+# ----------------------------
+
+def build_tcdecoder(new_channels = [512, 256, 128, 128],
+                                  device="cuda",
+                                  dtype=torch.bfloat16,
+                                  new_latent_channels=None):
+    """
+    构建“更宽”的 decoder；深度增强（IdentityConv2d+ReLU）已在 TAEHV 内部完成。
+    - 不创建 small / 不做移植
+    - base_ckpt_path 参数保留但不使用（接口兼容）
+
+    返回：big （单个模型）
+    """
+    if new_latent_channels is not None:
+        big = TAEHV(checkpoint_path=None, channels=new_channels, latent_channels=new_latent_channels).to(device).to(dtype).train()
+    else:
+        big = TAEHV(checkpoint_path=None, channels=new_channels).to(device).to(dtype).train()
+
+    big.clean_mem()
+    return big

flashvsr_arch/models/__init__.py

@@ -0,0 +1 @@
+from .model_manager import *

flashvsr_arch/models/model_manager.py

@@ -0,0 +1,402 @@
+import os, torch, json, importlib
+from typing import List
+
+from ..configs.model_config import model_loader_configs, huggingface_model_loader_configs, patch_model_loader_configs
+from .utils import load_state_dict, init_weights_on_device, hash_state_dict_keys, split_state_dict_with_prefix
+
+def load_model_from_single_file(state_dict, model_names, model_classes, model_resource, torch_dtype, device):
+    loaded_model_names, loaded_models = [], []
+    for model_name, model_class in zip(model_names, model_classes):
+        #print(f"    model_name: {model_name} model_class: {model_class.__name__}")
+        state_dict_converter = model_class.state_dict_converter()
+        if model_resource == "civitai":
+            state_dict_results = state_dict_converter.from_civitai(state_dict)
+        elif model_resource == "diffusers":
+            state_dict_results = state_dict_converter.from_diffusers(state_dict)
+        if isinstance(state_dict_results, tuple):
+            model_state_dict, extra_kwargs = state_dict_results
+            #print(f"        This model is initialized with extra kwargs: {extra_kwargs}")
+        else:
+            model_state_dict, extra_kwargs = state_dict_results, {}
+        torch_dtype = torch.float32 if extra_kwargs.get("upcast_to_float32", False) else torch_dtype
+        with init_weights_on_device():
+            model = model_class(**extra_kwargs)
+        if hasattr(model, "eval"):
+            model = model.eval()
+        model.load_state_dict(model_state_dict, assign=True)
+        model = model.to(dtype=torch_dtype, device=device)
+        loaded_model_names.append(model_name)
+        loaded_models.append(model)
+    return loaded_model_names, loaded_models
+
+
+def load_model_from_huggingface_folder(file_path, model_names, model_classes, torch_dtype, device):
+    loaded_model_names, loaded_models = [], []
+    for model_name, model_class in zip(model_names, model_classes):
+        if torch_dtype in [torch.float32, torch.float16, torch.bfloat16]:
+            model = model_class.from_pretrained(file_path, torch_dtype=torch_dtype).eval()
+        else:
+            model = model_class.from_pretrained(file_path).eval().to(dtype=torch_dtype)
+        if torch_dtype == torch.float16 and hasattr(model, "half"):
+            model = model.half()
+        try:
+            model = model.to(device=device)
+        except:
+            pass
+        loaded_model_names.append(model_name)
+        loaded_models.append(model)
+    return loaded_model_names, loaded_models
+
+
+def load_single_patch_model_from_single_file(state_dict, model_name, model_class, base_model, extra_kwargs, torch_dtype, device):
+    #print(f"    model_name: {model_name} model_class: {model_class.__name__} extra_kwargs: {extra_kwargs}")
+    base_state_dict = base_model.state_dict()
+    base_model.to("cpu")
+    del base_model
+    model = model_class(**extra_kwargs)
+    model.load_state_dict(base_state_dict, strict=False)
+    model.load_state_dict(state_dict, strict=False)
+    model.to(dtype=torch_dtype, device=device)
+    return model
+
+
+def load_patch_model_from_single_file(state_dict, model_names, model_classes, extra_kwargs, model_manager, torch_dtype, device):
+    loaded_model_names, loaded_models = [], []
+    for model_name, model_class in zip(model_names, model_classes):
+        while True:
+            for model_id in range(len(model_manager.model)):
+                base_model_name = model_manager.model_name[model_id]
+                if base_model_name == model_name:
+                    base_model_path = model_manager.model_path[model_id]
+                    base_model = model_manager.model[model_id]
+                    print(f"    Adding patch model to {base_model_name} ({base_model_path})")
+                    patched_model = load_single_patch_model_from_single_file(
+                        state_dict, model_name, model_class, base_model, extra_kwargs, torch_dtype, device)
+                    loaded_model_names.append(base_model_name)
+                    loaded_models.append(patched_model)
+                    model_manager.model.pop(model_id)
+                    model_manager.model_path.pop(model_id)
+                    model_manager.model_name.pop(model_id)
+                    break
+            else:
+                break
+    return loaded_model_names, loaded_models
+
+
+
+class ModelDetectorTemplate:
+    def __init__(self):
+        pass
+
+    def match(self, file_path="", state_dict={}):
+        return False
+    
+    def load(self, file_path="", state_dict={}, device="cuda", torch_dtype=torch.float16, **kwargs):
+        return [], []
+    
+
+
+class ModelDetectorFromSingleFile:
+    def __init__(self, model_loader_configs=[]):
+        self.keys_hash_with_shape_dict = {}
+        self.keys_hash_dict = {}
+        for metadata in model_loader_configs:
+            self.add_model_metadata(*metadata)
+
+
+    def add_model_metadata(self, keys_hash, keys_hash_with_shape, model_names, model_classes, model_resource):
+        self.keys_hash_with_shape_dict[keys_hash_with_shape] = (model_names, model_classes, model_resource)
+        if keys_hash is not None:
+            self.keys_hash_dict[keys_hash] = (model_names, model_classes, model_resource)
+
+
+    def match(self, file_path="", state_dict={}):
+        if isinstance(file_path, str) and os.path.isdir(file_path):
+            return False
+        if len(state_dict) == 0:
+            state_dict = load_state_dict(file_path)
+        keys_hash_with_shape = hash_state_dict_keys(state_dict, with_shape=True)
+        if keys_hash_with_shape in self.keys_hash_with_shape_dict:
+            return True
+        keys_hash = hash_state_dict_keys(state_dict, with_shape=False)
+        if keys_hash in self.keys_hash_dict:
+            return True
+        return False
+
+
+    def load(self, file_path="", state_dict={}, device="cuda", torch_dtype=torch.float16, **kwargs):
+        if len(state_dict) == 0:
+            state_dict = load_state_dict(file_path)
+
+        # Load models with strict matching
+        keys_hash_with_shape = hash_state_dict_keys(state_dict, with_shape=True)
+        if keys_hash_with_shape in self.keys_hash_with_shape_dict:
+            model_names, model_classes, model_resource = self.keys_hash_with_shape_dict[keys_hash_with_shape]
+            loaded_model_names, loaded_models = load_model_from_single_file(state_dict, model_names, model_classes, model_resource, torch_dtype, device)
+            return loaded_model_names, loaded_models
+
+        # Load models without strict matching
+        # (the shape of parameters may be inconsistent, and the state_dict_converter will modify the model architecture)
+        keys_hash = hash_state_dict_keys(state_dict, with_shape=False)
+        if keys_hash in self.keys_hash_dict:
+            model_names, model_classes, model_resource = self.keys_hash_dict[keys_hash]
+            loaded_model_names, loaded_models = load_model_from_single_file(state_dict, model_names, model_classes, model_resource, torch_dtype, device)
+            return loaded_model_names, loaded_models
+
+        return loaded_model_names, loaded_models
+
+
+
+class ModelDetectorFromSplitedSingleFile(ModelDetectorFromSingleFile):
+    def __init__(self, model_loader_configs=[]):
+        super().__init__(model_loader_configs)
+
+
+    def match(self, file_path="", state_dict={}):
+        if isinstance(file_path, str) and os.path.isdir(file_path):
+            return False
+        if len(state_dict) == 0:
+            state_dict = load_state_dict(file_path)
+        splited_state_dict = split_state_dict_with_prefix(state_dict)
+        for sub_state_dict in splited_state_dict:
+            if super().match(file_path, sub_state_dict):
+                return True
+        return False
+
+
+    def load(self, file_path="", state_dict={}, device="cuda", torch_dtype=torch.float16, **kwargs):
+        # Split the state_dict and load from each component
+        splited_state_dict = split_state_dict_with_prefix(state_dict)
+        valid_state_dict = {}
+        for sub_state_dict in splited_state_dict:
+            if super().match(file_path, sub_state_dict):
+                valid_state_dict.update(sub_state_dict)
+        if super().match(file_path, valid_state_dict):
+            loaded_model_names, loaded_models = super().load(file_path, valid_state_dict, device, torch_dtype)
+        else:
+            loaded_model_names, loaded_models = [], []
+            for sub_state_dict in splited_state_dict:
+                if super().match(file_path, sub_state_dict):
+                    loaded_model_names_, loaded_models_ = super().load(file_path, valid_state_dict, device, torch_dtype)
+                    loaded_model_names += loaded_model_names_
+                    loaded_models += loaded_models_
+        return loaded_model_names, loaded_models
+    
+
+
+class ModelDetectorFromHuggingfaceFolder:
+    def __init__(self, model_loader_configs=[]):
+        self.architecture_dict = {}
+        for metadata in model_loader_configs:
+            self.add_model_metadata(*metadata)
+
+
+    def add_model_metadata(self, architecture, huggingface_lib, model_name, redirected_architecture):
+        self.architecture_dict[architecture] = (huggingface_lib, model_name, redirected_architecture)
+
+
+    def match(self, file_path="", state_dict={}):
+        if not isinstance(file_path, str) or os.path.isfile(file_path):
+            return False
+        file_list = os.listdir(file_path)
+        if "config.json" not in file_list:
+            return False
+        with open(os.path.join(file_path, "config.json"), "r") as f:
+            config = json.load(f)
+        if "architectures" not in config and "_class_name" not in config:
+            return False
+        return True
+
+
+    def load(self, file_path="", state_dict={}, device="cuda", torch_dtype=torch.float16, **kwargs):
+        with open(os.path.join(file_path, "config.json"), "r") as f:
+            config = json.load(f)
+        loaded_model_names, loaded_models = [], []
+        architectures = config["architectures"] if "architectures" in config else [config["_class_name"]]
+        for architecture in architectures:
+            huggingface_lib, model_name, redirected_architecture = self.architecture_dict[architecture]
+            if redirected_architecture is not None:
+                architecture = redirected_architecture
+            model_class = importlib.import_module(huggingface_lib).__getattribute__(architecture)
+            loaded_model_names_, loaded_models_ = load_model_from_huggingface_folder(file_path, [model_name], [model_class], torch_dtype, device)
+            loaded_model_names += loaded_model_names_
+            loaded_models += loaded_models_
+        return loaded_model_names, loaded_models
+    
+
+
+class ModelDetectorFromPatchedSingleFile:
+    def __init__(self, model_loader_configs=[]):
+        self.keys_hash_with_shape_dict = {}
+        for metadata in model_loader_configs:
+            self.add_model_metadata(*metadata)
+
+
+    def add_model_metadata(self, keys_hash_with_shape, model_name, model_class, extra_kwargs):
+        self.keys_hash_with_shape_dict[keys_hash_with_shape] = (model_name, model_class, extra_kwargs)
+
+
+    def match(self, file_path="", state_dict={}):
+        if not isinstance(file_path, str) or os.path.isdir(file_path):
+            return False
+        if len(state_dict) == 0:
+            state_dict = load_state_dict(file_path)
+        keys_hash_with_shape = hash_state_dict_keys(state_dict, with_shape=True)
+        if keys_hash_with_shape in self.keys_hash_with_shape_dict:
+            return True
+        return False
+
+
+    def load(self, file_path="", state_dict={}, device="cuda", torch_dtype=torch.float16, model_manager=None, **kwargs):
+        if len(state_dict) == 0:
+            state_dict = load_state_dict(file_path)
+
+        # Load models with strict matching
+        loaded_model_names, loaded_models = [], []
+        keys_hash_with_shape = hash_state_dict_keys(state_dict, with_shape=True)
+        if keys_hash_with_shape in self.keys_hash_with_shape_dict:
+            model_names, model_classes, extra_kwargs = self.keys_hash_with_shape_dict[keys_hash_with_shape]
+            loaded_model_names_, loaded_models_ = load_patch_model_from_single_file(
+                state_dict, model_names, model_classes, extra_kwargs, model_manager, torch_dtype, device)
+            loaded_model_names += loaded_model_names_
+            loaded_models += loaded_models_
+        return loaded_model_names, loaded_models
+
+
+
+class ModelManager:
+    def __init__(
+        self,
+        torch_dtype=torch.float16,
+        device="cuda",
+        file_path_list: List[str] = [],
+    ):
+        self.torch_dtype = torch_dtype
+        self.device = device
+        self.model = []
+        self.model_path = []
+        self.model_name = []
+        self.model_detector = [
+            ModelDetectorFromSingleFile(model_loader_configs),
+            ModelDetectorFromSplitedSingleFile(model_loader_configs),
+            ModelDetectorFromHuggingfaceFolder(huggingface_model_loader_configs),
+            ModelDetectorFromPatchedSingleFile(patch_model_loader_configs),
+        ]
+        self.load_models(file_path_list)
+
+
+    def load_model_from_single_file(self, file_path="", state_dict={}, model_names=[], model_classes=[], model_resource=None):
+        print(f"Loading models from file: {file_path}")
+        if len(state_dict) == 0:
+            state_dict = load_state_dict(file_path)
+        model_names, models = load_model_from_single_file(state_dict, model_names, model_classes, model_resource, self.torch_dtype, self.device)
+        for model_name, model in zip(model_names, models):
+            self.model.append(model)
+            self.model_path.append(file_path)
+            self.model_name.append(model_name)
+        #print(f"    The following models are loaded: {model_names}.")
+
+
+    def load_model_from_huggingface_folder(self, file_path="", model_names=[], model_classes=[]):
+        print(f"Loading models from folder: {file_path}")
+        model_names, models = load_model_from_huggingface_folder(file_path, model_names, model_classes, self.torch_dtype, self.device)
+        for model_name, model in zip(model_names, models):
+            self.model.append(model)
+            self.model_path.append(file_path)
+            self.model_name.append(model_name)
+        #print(f"    The following models are loaded: {model_names}.")
+
+
+    def load_patch_model_from_single_file(self, file_path="", state_dict={}, model_names=[], model_classes=[], extra_kwargs={}):
+        print(f"Loading patch models from file: {file_path}")
+        model_names, models = load_patch_model_from_single_file(
+            state_dict, model_names, model_classes, extra_kwargs, self, self.torch_dtype, self.device)
+        for model_name, model in zip(model_names, models):
+            self.model.append(model)
+            self.model_path.append(file_path)
+            self.model_name.append(model_name)
+        print(f"    The following patched models are loaded: {model_names}.")
+
+
+    def load_lora(self, file_path="", state_dict={}, lora_alpha=1.0):
+        if isinstance(file_path, list):
+            for file_path_ in file_path:
+                self.load_lora(file_path_, state_dict=state_dict, lora_alpha=lora_alpha)
+        else:
+            print(f"Loading LoRA models from file: {file_path}")
+            is_loaded = False
+            if len(state_dict) == 0:
+                state_dict = load_state_dict(file_path)
+            for model_name, model, model_path in zip(self.model_name, self.model, self.model_path):
+                for lora in get_lora_loaders():
+                    match_results = lora.match(model, state_dict)
+                    if match_results is not None:
+                        print(f"    Adding LoRA to {model_name} ({model_path}).")
+                        lora_prefix, model_resource = match_results
+                        lora.load(model, state_dict, lora_prefix, alpha=lora_alpha, model_resource=model_resource)
+                        is_loaded = True
+                        break
+            if not is_loaded:
+                print(f"    Cannot load LoRA: {file_path}")
+
+
+    def load_model(self, file_path, model_names=None, device=None, torch_dtype=None):
+        #print(f"Loading models from: {file_path}")
+        if device is None: device = self.device
+        if torch_dtype is None: torch_dtype = self.torch_dtype
+        if isinstance(file_path, list):
+            state_dict = {}
+            for path in file_path:
+                state_dict.update(load_state_dict(path))
+        elif os.path.isfile(file_path):
+            state_dict = load_state_dict(file_path)
+        else:
+            state_dict = None
+        for model_detector in self.model_detector:
+            if model_detector.match(file_path, state_dict):
+                model_names, models = model_detector.load(
+                    file_path, state_dict,
+                    device=device, torch_dtype=torch_dtype,
+                    allowed_model_names=model_names, model_manager=self
+                )
+                for model_name, model in zip(model_names, models):
+                    self.model.append(model)
+                    self.model_path.append(file_path)
+                    self.model_name.append(model_name)
+                #print(f"    The following models are loaded: {model_names}.")
+                break
+        else:
+            print(f"    We cannot detect the model type. No models are loaded.")
+        
+
+    def load_models(self, file_path_list, model_names=None, device=None, torch_dtype=None):
+        for file_path in file_path_list:
+            self.load_model(file_path, model_names, device=device, torch_dtype=torch_dtype)
+
+    
+    def fetch_model(self, model_name, file_path=None, require_model_path=False):
+        fetched_models = []
+        fetched_model_paths = []
+        for model, model_path, model_name_ in zip(self.model, self.model_path, self.model_name):
+            if file_path is not None and file_path != model_path:
+                continue
+            if model_name == model_name_:
+                fetched_models.append(model)
+                fetched_model_paths.append(model_path)
+        if len(fetched_models) == 0:
+            #print(f"No {model_name} models available.")
+            return None
+        if len(fetched_models) == 1:
+            print(f"Using {model_name} from {fetched_model_paths[0]}")
+        else:
+            print(f"More than one {model_name} models are loaded in model manager: {fetched_model_paths}. Using {model_name} from {fetched_model_paths[0]}")
+        if require_model_path:
+            return fetched_models[0], fetched_model_paths[0]
+        else:
+            return fetched_models[0]
+        
+
+    def to(self, device):
+        for model in self.model:
+            model.to(device)
+

flashvsr_arch/models/utils.py

@@ -0,0 +1,360 @@
+import torch, os, gc
+from safetensors import safe_open
+from contextlib import contextmanager
+from einops import rearrange, repeat
+import torch.nn as nn
+import torch.nn.functional as F
+from tqdm import tqdm
+import time
+import hashlib
+
+CACHE_T = 2
+
+@contextmanager
+def init_weights_on_device(device = torch.device("meta"), include_buffers :bool = False):
+    
+    old_register_parameter = torch.nn.Module.register_parameter
+    if include_buffers:
+        old_register_buffer = torch.nn.Module.register_buffer
+    
+    def register_empty_parameter(module, name, param):
+        old_register_parameter(module, name, param)
+        if param is not None:
+            param_cls = type(module._parameters[name])
+            kwargs = module._parameters[name].__dict__
+            kwargs["requires_grad"] = param.requires_grad
+            module._parameters[name] = param_cls(module._parameters[name].to(device), **kwargs)
+
+    def register_empty_buffer(module, name, buffer, persistent=True):
+        old_register_buffer(module, name, buffer, persistent=persistent)
+        if buffer is not None:
+            module._buffers[name] = module._buffers[name].to(device)
+            
+    def patch_tensor_constructor(fn):
+        def wrapper(*args, **kwargs):
+            kwargs["device"] = device
+            return fn(*args, **kwargs)
+
+        return wrapper
+    
+    if include_buffers:
+        tensor_constructors_to_patch = {
+            torch_function_name: getattr(torch, torch_function_name)
+            for torch_function_name in ["empty", "zeros", "ones", "full"]
+        }
+    else:
+        tensor_constructors_to_patch = {}
+    
+    try:
+        torch.nn.Module.register_parameter = register_empty_parameter
+        if include_buffers:
+            torch.nn.Module.register_buffer = register_empty_buffer
+        for torch_function_name in tensor_constructors_to_patch.keys():
+            setattr(torch, torch_function_name, patch_tensor_constructor(getattr(torch, torch_function_name)))
+        yield
+    finally:
+        torch.nn.Module.register_parameter = old_register_parameter
+        if include_buffers:
+            torch.nn.Module.register_buffer = old_register_buffer
+        for torch_function_name, old_torch_function in tensor_constructors_to_patch.items():
+            setattr(torch, torch_function_name, old_torch_function)
+
+def load_state_dict_from_folder(file_path, torch_dtype=None):
+    state_dict = {}
+    for file_name in os.listdir(file_path):
+        if "." in file_name and file_name.split(".")[-1] in [
+            "safetensors", "bin", "ckpt", "pth", "pt"
+        ]:
+            state_dict.update(load_state_dict(os.path.join(file_path, file_name), torch_dtype=torch_dtype))
+    return state_dict
+
+
+def load_state_dict(file_path, torch_dtype=None):
+    if file_path.endswith(".safetensors"):
+        return load_state_dict_from_safetensors(file_path, torch_dtype=torch_dtype)
+    else:
+        return load_state_dict_from_bin(file_path, torch_dtype=torch_dtype)
+
+
+def load_state_dict_from_safetensors(file_path, torch_dtype=None):
+    state_dict = {}
+    with safe_open(file_path, framework="pt", device="cpu") as f:
+        for k in f.keys():
+            state_dict[k] = f.get_tensor(k)
+            if torch_dtype is not None:
+                state_dict[k] = state_dict[k].to(torch_dtype)
+    return state_dict
+
+
+def load_state_dict_from_bin(file_path, torch_dtype=None):
+    state_dict = torch.load(file_path, map_location="cpu", weights_only=True)
+    if torch_dtype is not None:
+        for i in state_dict:
+            if isinstance(state_dict[i], torch.Tensor):
+                state_dict[i] = state_dict[i].to(torch_dtype)
+    return state_dict
+
+
+def search_for_embeddings(state_dict):
+    embeddings = []
+    for k in state_dict:
+        if isinstance(state_dict[k], torch.Tensor):
+            embeddings.append(state_dict[k])
+        elif isinstance(state_dict[k], dict):
+            embeddings += search_for_embeddings(state_dict[k])
+    return embeddings
+
+
+def search_parameter(param, state_dict):
+    for name, param_ in state_dict.items():
+        if param.numel() == param_.numel():
+            if param.shape == param_.shape:
+                if torch.dist(param, param_) < 1e-3:
+                    return name
+            else:
+                if torch.dist(param.flatten(), param_.flatten()) < 1e-3:
+                    return name
+    return None
+
+
+def build_rename_dict(source_state_dict, target_state_dict, split_qkv=False):
+    matched_keys = set()
+    with torch.no_grad():
+        for name in source_state_dict:
+            rename = search_parameter(source_state_dict[name], target_state_dict)
+            if rename is not None:
+                print(f'"{name}": "{rename}",')
+                matched_keys.add(rename)
+            elif split_qkv and len(source_state_dict[name].shape)>=1 and source_state_dict[name].shape[0]%3==0:
+                length = source_state_dict[name].shape[0] // 3
+                rename = []
+                for i in range(3):
+                    rename.append(search_parameter(source_state_dict[name][i*length: i*length+length], target_state_dict))
+                if None not in rename:
+                    print(f'"{name}": {rename},')
+                    for rename_ in rename:
+                        matched_keys.add(rename_)
+    for name in target_state_dict:
+        if name not in matched_keys:
+            print("Cannot find", name, target_state_dict[name].shape)
+
+
+def search_for_files(folder, extensions):
+    files = []
+    if os.path.isdir(folder):
+        for file in sorted(os.listdir(folder)):
+            files += search_for_files(os.path.join(folder, file), extensions)
+    elif os.path.isfile(folder):
+        for extension in extensions:
+            if folder.endswith(extension):
+                files.append(folder)
+                break
+    return files
+
+
+def convert_state_dict_keys_to_single_str(state_dict, with_shape=True):
+    keys = []
+    for key, value in state_dict.items():
+        if isinstance(key, str):
+            if isinstance(value, torch.Tensor):
+                if with_shape:
+                    shape = "_".join(map(str, list(value.shape)))
+                    keys.append(key + ":" + shape)
+                keys.append(key)
+            elif isinstance(value, dict):
+                keys.append(key + "|" + convert_state_dict_keys_to_single_str(value, with_shape=with_shape))
+    keys.sort()
+    keys_str = ",".join(keys)
+    return keys_str
+
+
+def split_state_dict_with_prefix(state_dict):
+    keys = sorted([key for key in state_dict if isinstance(key, str)])
+    prefix_dict = {}
+    for key in  keys:
+        prefix = key if "." not in key else key.split(".")[0]
+        if prefix not in prefix_dict:
+            prefix_dict[prefix] = []
+        prefix_dict[prefix].append(key)
+    state_dicts = []
+    for prefix, keys in prefix_dict.items():
+        sub_state_dict = {key: state_dict[key] for key in keys}
+        state_dicts.append(sub_state_dict)
+    return state_dicts
+
+def hash_state_dict_keys(state_dict, with_shape=True):
+    keys_str = convert_state_dict_keys_to_single_str(state_dict, with_shape=with_shape)
+    keys_str = keys_str.encode(encoding="UTF-8")
+    return hashlib.md5(keys_str).hexdigest()
+
+def clean_vram():
+    gc.collect()
+    if torch.cuda.is_available():
+        torch.cuda.empty_cache()
+        torch.cuda.ipc_collect()
+    if torch.mps.is_available():
+        torch.mps.empty_cache()
+
+def get_device_list():
+    devs = []
+    if torch.cuda.is_available():
+        devs += [f"cuda:{i}" for i in range(torch.cuda.device_count())]
+    
+    if torch.mps.is_available():
+        devs += [f"mps:{i}" for i in range(torch.mps.device_count())]
+    
+    return devs
+
+class RMS_norm(nn.Module):
+    
+    def __init__(self, dim, channel_first=True, images=True, bias=False):
+        super().__init__()
+        broadcastable_dims = (1, 1, 1) if not images else (1, 1)
+        shape = (dim, *broadcastable_dims) if channel_first else (dim,)
+        
+        self.channel_first = channel_first
+        self.scale = dim**0.5
+        self.gamma = nn.Parameter(torch.ones(shape))
+        self.bias = nn.Parameter(torch.zeros(shape)) if bias else 0.
+        
+    def forward(self, x):
+        return F.normalize(
+            x, dim=(1 if self.channel_first else
+                    -1)) * self.scale * self.gamma + self.bias
+    
+class CausalConv3d(nn.Conv3d):
+    """
+    Causal 3d convolusion.
+    """
+    
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self._padding = (self.padding[2], self.padding[2], self.padding[1],
+                         self.padding[1], 2 * self.padding[0], 0)
+        self.padding = (0, 0, 0)
+        
+    def forward(self, x, cache_x=None):
+        padding = list(self._padding)
+        if cache_x is not None and self._padding[4] > 0:
+            cache_x = cache_x.to(x.device)
+            # print(cache_x.shape, x.shape)
+            x = torch.cat([cache_x, x], dim=2)
+            padding[4] -= cache_x.shape[2]
+            # print('cache!')
+        x = F.pad(x, padding, mode='replicate') # mode='replicate'
+        # print(x[0,0,:,0,0])
+        
+        return super().forward(x)
+    
+class PixelShuffle3d(nn.Module):
+    def __init__(self, ff, hh, ww):
+        super().__init__()
+        self.ff = ff
+        self.hh = hh
+        self.ww = ww
+        
+    def forward(self, x):
+        # x: (B, C, F, H, W)
+        return rearrange(x, 
+                         'b c (f ff) (h hh) (w ww) -> b (c ff hh ww) f h w',
+                         ff=self.ff, hh=self.hh, ww=self.ww)
+    
+class Buffer_LQ4x_Proj(nn.Module):
+    
+    def __init__(self, in_dim, out_dim, layer_num=30):
+        super().__init__()
+        self.ff = 1
+        self.hh = 16
+        self.ww = 16
+        self.hidden_dim1 = 2048
+        self.hidden_dim2 = 3072
+        self.layer_num = layer_num
+        
+        self.pixel_shuffle = PixelShuffle3d(self.ff, self.hh, self.ww)
+        
+        self.conv1 = CausalConv3d(in_dim*self.ff*self.hh*self.ww, self.hidden_dim1, (4, 3, 3), stride=(2, 1, 1), padding=(1, 1, 1)) # f -> f/2 h -> h w -> w
+        self.norm1 = RMS_norm(self.hidden_dim1, images=False)
+        self.act1 = nn.SiLU()
+        
+        self.conv2 = CausalConv3d(self.hidden_dim1, self.hidden_dim2, (4, 3, 3), stride=(2, 1, 1), padding=(1, 1, 1)) # f -> f/2 h -> h w -> w
+        self.norm2 = RMS_norm(self.hidden_dim2, images=False)
+        self.act2 = nn.SiLU()
+        
+        self.linear_layers = nn.ModuleList([nn.Linear(self.hidden_dim2, out_dim) for _ in range(layer_num)])
+        
+        self.clip_idx = 0
+        
+    def forward(self, video):
+        self.clear_cache()
+        # x: (B, C, F, H, W)
+        
+        t = video.shape[2]
+        iter_ = 1 + (t - 1) // 4
+        first_frame = video[:, :, :1, :, :].repeat(1, 1, 3, 1, 1)
+        video = torch.cat([first_frame, video], dim=2)
+        # print(video.shape)
+        
+        out_x = []
+        for i in range(iter_):
+            x = self.pixel_shuffle(video[:,:,i*4:(i+1)*4,:,:])
+            cache1_x = x[:, :, -CACHE_T:, :, :].clone()
+            self.cache['conv1'] = cache1_x
+            x = self.conv1(x, self.cache['conv1'])
+            x = self.norm1(x)
+            x = self.act1(x)
+            cache2_x = x[:, :, -CACHE_T:, :, :].clone()
+            self.cache['conv2'] = cache2_x
+            if i == 0:
+                continue
+            x = self.conv2(x, self.cache['conv2'])
+            x = self.norm2(x)
+            x = self.act2(x)
+            out_x.append(x)
+        out_x = torch.cat(out_x, dim = 2)
+        # print(out_x.shape)
+        out_x = rearrange(out_x, 'b c f h w -> b (f h w) c')
+        outputs = []
+        for i in range(self.layer_num):
+            outputs.append(self.linear_layers[i](out_x))
+        return outputs
+    
+    def clear_cache(self):
+        self.cache = {}
+        self.cache['conv1'] = None
+        self.cache['conv2'] = None
+        self.clip_idx = 0
+        
+    def stream_forward(self, video_clip):
+        if self.clip_idx == 0:
+            # self.clear_cache()
+            first_frame = video_clip[:, :, :1, :, :].repeat(1, 1, 3, 1, 1)
+            video_clip = torch.cat([first_frame, video_clip], dim=2)
+            x = self.pixel_shuffle(video_clip)
+            cache1_x = x[:, :, -CACHE_T:, :, :].clone()
+            self.cache['conv1'] = cache1_x
+            x = self.conv1(x, self.cache['conv1'])
+            x = self.norm1(x)
+            x = self.act1(x)
+            cache2_x = x[:, :, -CACHE_T:, :, :].clone()
+            self.cache['conv2'] = cache2_x
+            self.clip_idx += 1
+            return None
+        else:
+            x = self.pixel_shuffle(video_clip)
+            cache1_x = x[:, :, -CACHE_T:, :, :].clone()
+            self.cache['conv1'] = cache1_x
+            x = self.conv1(x, self.cache['conv1'])
+            x = self.norm1(x)
+            x = self.act1(x)
+            cache2_x = x[:, :, -CACHE_T:, :, :].clone()
+            self.cache['conv2'] = cache2_x
+            x = self.conv2(x, self.cache['conv2'])
+            x = self.norm2(x)
+            x = self.act2(x)
+            out_x = rearrange(x, 'b c f h w -> b (f h w) c')
+            outputs = []
+            for i in range(self.layer_num):
+                outputs.append(self.linear_layers[i](out_x))
+            self.clip_idx += 1
+            return outputs
+        

flashvsr_arch/models/wan_video_dit.py

@@ -0,0 +1,834 @@
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+import math
+import random
+import os
+import time
+from typing import Tuple, Optional, List
+from einops import rearrange
+from .utils import hash_state_dict_keys
+
+try:
+    import flash_attn_interface
+    FLASH_ATTN_3_AVAILABLE = True
+except ModuleNotFoundError:
+    FLASH_ATTN_3_AVAILABLE = False
+
+try:
+    import flash_attn
+    FLASH_ATTN_2_AVAILABLE = True
+except ModuleNotFoundError:
+    FLASH_ATTN_2_AVAILABLE = False
+
+try:
+    from sageattention import sageattn
+    SAGE_ATTN_AVAILABLE = True
+except ModuleNotFoundError:
+    SAGE_ATTN_AVAILABLE = False
+
+try:
+    from sageattn.core import sparse_sageattn
+    SPARSE_SAGE_AVAILABLE = True
+except ModuleNotFoundError:
+    SPARSE_SAGE_AVAILABLE = False
+    sparse_sageattn = None
+from PIL import Image
+import numpy as np
+
+
+# ----------------------------
+# Local / window masks
+# ----------------------------
+@torch.no_grad()
+def build_local_block_mask_shifted_vec(block_h: int,
+                                       block_w: int,
+                                       win_h: int = 6,
+                                       win_w: int = 6,
+                                       include_self: bool = True,
+                                       device=None) -> torch.Tensor:
+    device = device or torch.device("cpu")
+    H, W = block_h, block_w
+    r = torch.arange(H, device=device)
+    c = torch.arange(W, device=device)
+    YY, XX = torch.meshgrid(r, c, indexing="ij")
+    r_all = YY.reshape(-1)
+    c_all = XX.reshape(-1)
+    r_half = win_h // 2
+    c_half = win_w // 2
+    start_r = torch.clamp(r_all - r_half, 0, H - win_h)
+    end_r   = start_r + win_h - 1
+    start_c = torch.clamp(c_all - c_half, 0, W - win_w)
+    end_c   = start_c + win_w - 1
+    in_row = (r_all[None, :] >= start_r[:, None]) & (r_all[None, :] <= end_r[:, None])
+    in_col = (c_all[None, :] >= start_c[:, None]) & (c_all[None, :] <= end_c[:, None])
+    mask = in_row & in_col
+    if not include_self:
+        mask.fill_diagonal_(False)
+    return mask
+
+@torch.no_grad()
+def build_local_block_mask_shifted_vec_normal_slide(block_h: int,
+                                                   block_w: int,
+                                                   win_h: int = 6,
+                                                   win_w: int = 6,
+                                                   include_self: bool = True,
+                                                   device=None) -> torch.Tensor:
+    device = device or torch.device("cpu")
+    H, W = block_h, block_w
+    r = torch.arange(H, device=device)
+    c = torch.arange(W, device=device)
+    YY, XX = torch.meshgrid(r, c, indexing="ij")
+    r_all = YY.reshape(-1)
+    c_all = XX.reshape(-1)
+    r_half = win_h // 2
+    c_half = win_w // 2
+    start_r = r_all - r_half
+    end_r   = start_r + win_h - 1
+    start_c = c_all - c_half
+    end_c   = start_c + win_w - 1
+    in_row = (r_all[None, :] >= start_r[:, None]) & (r_all[None, :] <= end_r[:, None])
+    in_col = (c_all[None, :] >= start_c[:, None]) & (c_all[None, :] <= end_c[:, None])
+    mask = in_row & in_col
+    if not include_self:
+        mask.fill_diagonal_(False)
+    return mask
+
+
+class WindowPartition3D:
+    """Partition / reverse-partition helpers for 5-D tensors (B,F,H,W,C)."""
+    @staticmethod
+    def partition(x: torch.Tensor, win: Tuple[int, int, int]):
+        B, F, H, W, C = x.shape
+        wf, wh, ww = win
+        assert F % wf == 0 and H % wh == 0 and W % ww == 0, "Dims must divide by window size."
+        x = x.view(B, F // wf, wf, H // wh, wh, W // ww, ww, C)
+        x = x.permute(0, 1, 3, 5, 2, 4, 6, 7).contiguous()
+        return x.view(-1, wf * wh * ww, C)
+
+    @staticmethod
+    def reverse(windows: torch.Tensor, win: Tuple[int, int, int], orig: Tuple[int, int, int]):
+        F, H, W = orig
+        wf, wh, ww = win
+        nf, nh, nw = F // wf, H // wh, W // ww
+        B = windows.size(0) // (nf * nh * nw)
+        x = windows.view(B, nf, nh, nw, wf, wh, ww, -1)
+        x = x.permute(0, 1, 4, 2, 5, 3, 6, 7).contiguous()
+        return x.view(B, F, H, W, -1)
+
+
+@torch.no_grad()
+def generate_draft_block_mask(batch_size, nheads, seqlen,
+                              q_w, k_w, topk=10, local_attn_mask=None):
+    assert batch_size == 1, "Only batch_size=1 supported for now"
+    assert local_attn_mask is not None, "local_attn_mask must be provided"
+    avgpool_q = torch.mean(q_w, dim=1) 
+    avgpool_k = torch.mean(k_w, dim=1)
+    avgpool_q = rearrange(avgpool_q, 's (h d) -> s h d', h=nheads)
+    avgpool_k = rearrange(avgpool_k, 's (h d) -> s h d', h=nheads)
+    q_heads = avgpool_q.permute(1, 0, 2)
+    k_heads = avgpool_k.permute(1, 0, 2)
+    D = avgpool_q.shape[-1]
+    scores = torch.einsum("hld,hmd->hlm", q_heads, k_heads) / math.sqrt(D)
+
+    repeat_head = scores.shape[0]
+    repeat_len = scores.shape[1] // local_attn_mask.shape[0]
+    repeat_num = scores.shape[2] // local_attn_mask.shape[1]
+    local_attn_mask = local_attn_mask.unsqueeze(1).unsqueeze(0).repeat(repeat_len, 1, repeat_num, 1)
+    local_attn_mask = rearrange(local_attn_mask, 'x a y b -> (x a) (y b)')
+    local_attn_mask = local_attn_mask.unsqueeze(0).repeat(repeat_head, 1, 1)
+    local_attn_mask = local_attn_mask.to(torch.float32)
+    local_attn_mask = local_attn_mask.masked_fill(local_attn_mask == False, -float('inf'))
+    local_attn_mask = local_attn_mask.masked_fill(local_attn_mask == True, 0)
+    scores = scores + local_attn_mask
+
+    attn_map = torch.softmax(scores, dim=-1)
+    attn_map = rearrange(attn_map, 'h (it s1) s2 -> (h it) s1 s2', it=seqlen)
+    loop_num, s1, s2 = attn_map.shape
+    flat = attn_map.reshape(loop_num, -1)
+    n = flat.shape[1]
+    apply_topk = min(flat.shape[1]-1, topk)
+    thresholds = torch.topk(flat, k=apply_topk + 1, dim=1, largest=True).values[:, -1]
+    thresholds = thresholds.unsqueeze(1)
+    mask_new = (flat > thresholds).reshape(loop_num, s1, s2)
+    mask_new = rearrange(mask_new, '(h it) s1 s2 -> h (it s1) s2', it=seqlen)  # keep shape note
+    # 修正：上行变量名统一
+    # mask_new = rearrange(attn_map, 'h (it s1) s2 -> h (it s1) s2', it=seqlen) * 0 + mask_new
+    mask = mask_new.unsqueeze(0).repeat(batch_size, 1, 1, 1)
+    mask = mask.repeat_interleave(2, dim=-1)
+    return mask
+
+
+@torch.no_grad()
+def generate_draft_block_mask_refined(batch_size, nheads, seqlen,
+                                      q_w, k_w, topk=10, local_attn_mask=None):
+    assert batch_size == 1, "Only batch_size=1 supported for now"
+    assert local_attn_mask is not None, "local_attn_mask must be provided"
+    
+    avgpool_q = torch.mean(q_w, dim=1) 
+    avgpool_q = rearrange(avgpool_q, 's (h d) -> s h d', h=nheads)
+    q_heads = avgpool_q.permute(1, 0, 2)
+    
+    k_w_split = k_w.view(k_w.shape[0], 2, 64, k_w.shape[2])
+    avgpool_k_split = torch.mean(k_w_split, dim=2)
+    avgpool_k_refined = rearrange(avgpool_k_split, 's two d -> (s two) d', two=2)
+    avgpool_k_refined = rearrange(avgpool_k_refined, 's (h d) -> s h d', h=nheads)
+    k_heads = avgpool_k_refined.permute(1, 0, 2)
+    
+    D = avgpool_q.shape[-1]
+    scores = torch.einsum("hld,hmd->hlm", q_heads, k_heads) / math.sqrt(D)
+    
+    repeat_head = scores.shape[0]
+    num_q_blocks_local = local_attn_mask.shape[0]
+    num_k_blocks_local = local_attn_mask.shape[1]
+    
+    local_attn_mask = local_attn_mask.repeat_interleave(2, dim=1)
+    
+    repeat_len = scores.shape[1] // local_attn_mask.shape[0]
+    repeat_num = scores.shape[2] // local_attn_mask.shape[1]
+    
+    local_attn_mask = local_attn_mask.unsqueeze(0).repeat(repeat_head, 1, 1)
+    
+    local_attn_mask = local_attn_mask.to(torch.float32)
+    local_attn_mask = local_attn_mask.masked_fill(local_attn_mask == False, -float('inf'))
+    local_attn_mask = local_attn_mask.masked_fill(local_attn_mask == True, 0)
+    
+    assert scores.shape == local_attn_mask.shape
+    
+    scores = scores + local_attn_mask
+    attn_map = torch.softmax(scores, dim=-1)
+    attn_map = rearrange(attn_map, 'h (it s1) s2 -> (h it) s1 s2', it=seqlen) # it=seqlen可能需要调整，取决于seqlen的含义
+    loop_num, s1, s2 = attn_map.shape
+    flat = attn_map.reshape(loop_num, -1)
+    apply_topk = min(flat.shape[1]-1, topk)
+    thresholds = torch.topk(flat, k=apply_topk + 1, dim=1, largest=True).values[:, -1]
+    thresholds = thresholds.unsqueeze(1)
+    mask_new = (flat > thresholds).reshape(loop_num, s1, s2)
+    mask_new = rearrange(mask_new, '(h it) s1 s2 -> h (it s1) s2', it=seqlen)
+    
+    mask = mask_new.unsqueeze(0).repeat(batch_size, 1, 1, 1)
+    
+    return mask
+
+
+# ----------------------------
+# Attention kernels
+# ----------------------------
+def flash_attention(q: torch.Tensor, k: torch.Tensor, v: torch.Tensor, num_heads: int, compatibility_mode=False, attention_mask=None, return_KV=False, enable_sageattention=True):
+    if attention_mask is not None and enable_sageattention and SPARSE_SAGE_AVAILABLE:
+        seqlen = q.shape[1]
+        seqlen_kv = k.shape[1]
+        q = rearrange(q, "b s (n d) -> b n s d", n=num_heads)
+        k = rearrange(k, "b s (n d) -> b n s d", n=num_heads)
+        v = rearrange(v, "b s (n d) -> b n s d", n=num_heads)
+        base_blockmask = attention_mask
+        x = sparse_sageattn(
+            q, k, v,
+            mask_id=base_blockmask.to(torch.int8),
+            is_causal=False,
+            tensor_layout="HND"
+        )
+        x = rearrange(x, "b n s d -> b s (n d)", n=num_heads)
+    elif compatibility_mode:
+        q = rearrange(q, "b s (n d) -> b n s d", n=num_heads)
+        k = rearrange(k, "b s (n d) -> b n s d", n=num_heads)
+        v = rearrange(v, "b s (n d) -> b n s d", n=num_heads)
+        x = F.scaled_dot_product_attention(q, k, v)
+        x = rearrange(x, "b n s d -> b s (n d)", n=num_heads)
+    elif FLASH_ATTN_3_AVAILABLE:
+        q = rearrange(q, "b s (n d) -> b s n d", n=num_heads)
+        k = rearrange(k, "b s (n d) -> b s n d", n=num_heads)
+        v = rearrange(v, "b s (n d) -> b s n d", n=num_heads)
+        x = flash_attn_interface.flash_attn_func(q, k, v)
+        if isinstance(x, tuple):
+            x = x[0]
+        x = rearrange(x, "b s n d -> b s (n d)", n=num_heads)
+    elif FLASH_ATTN_2_AVAILABLE:
+        q = rearrange(q, "b s (n d) -> b s n d", n=num_heads)
+        k = rearrange(k, "b s (n d) -> b s n d", n=num_heads)
+        v = rearrange(v, "b s (n d) -> b s n d", n=num_heads)
+        x = flash_attn.flash_attn_func(q, k, v)
+        x = rearrange(x, "b s n d -> b s (n d)", n=num_heads)
+    elif SAGE_ATTN_AVAILABLE:
+        q = rearrange(q, "b s (n d) -> b n s d", n=num_heads)
+        k = rearrange(k, "b s (n d) -> b n s d", n=num_heads)
+        v = rearrange(v, "b s (n d) -> b n s d", n=num_heads)
+        x = sageattn(q, k, v)
+        x = rearrange(x, "b n s d -> b s (n d)", n=num_heads)
+    else:
+        q = rearrange(q, "b s (n d) -> b n s d", n=num_heads)
+        k = rearrange(k, "b s (n d) -> b n s d", n=num_heads)
+        v = rearrange(v, "b s (n d) -> b n s d", n=num_heads)
+        x = F.scaled_dot_product_attention(q, k, v)
+        x = rearrange(x, "b n s d -> b s (n d)", n=num_heads)
+    return x
+
+
+def modulate(x: torch.Tensor, shift: torch.Tensor, scale: torch.Tensor):
+    return (x * (1 + scale) + shift)
+
+
+def sinusoidal_embedding_1d(dim, position):
+    half_dim = max(dim // 2, 1)
+    scale = torch.arange(half_dim, dtype=torch.float32, device=position.device)
+    inv_freq = torch.pow(10000.0, -scale / half_dim)
+    sinusoid = torch.outer(position.to(torch.float32), inv_freq)
+    x = torch.cat([torch.cos(sinusoid), torch.sin(sinusoid)], dim=1)
+    return x.to(position.dtype)
+
+
+def precompute_freqs_cis_3d(dim: int, end: int = 1024, theta: float = 10000.0):
+    f_freqs_cis = precompute_freqs_cis(dim - 2 * (dim // 3), end, theta)
+    h_freqs_cis = precompute_freqs_cis(dim // 3, end, theta)
+    w_freqs_cis = precompute_freqs_cis(dim // 3, end, theta)
+    return f_freqs_cis, h_freqs_cis, w_freqs_cis
+
+
+def precompute_freqs_cis(dim: int, end: int = 1024, theta: float = 10000.0):
+    half_dim = max(dim // 2, 1)
+    base = torch.arange(0, dim, 2, dtype=torch.float32)[:half_dim]
+    freqs = torch.pow(theta, -base / max(dim, 1))
+    steps = torch.arange(end, dtype=torch.float32)
+    angles = torch.outer(steps, freqs)
+    return torch.polar(torch.ones_like(angles), angles)
+
+
+def rope_apply(x, freqs, num_heads):
+    x = rearrange(x, "b s (n d) -> b s n d", n=num_heads)
+    orig_dtype = x.dtype
+    work_dtype = torch.float32 if orig_dtype in (torch.float16, torch.bfloat16) else orig_dtype
+    reshaped = x.to(work_dtype).reshape(x.shape[0], x.shape[1], x.shape[2], -1, 2)
+    x_complex = torch.view_as_complex(reshaped)
+    freqs = freqs.to(dtype=x_complex.dtype, device=x_complex.device)
+    x_out = torch.view_as_real(x_complex * freqs).flatten(2)
+    return x_out.to(orig_dtype)
+
+
+# ----------------------------
+# Norms & Blocks
+# ----------------------------
+class RMSNorm(nn.Module):
+    def __init__(self, dim, eps=1e-5):
+        super().__init__()
+        self.eps = eps
+        self.weight = nn.Parameter(torch.ones(dim))
+
+    def norm(self, x):
+        return x * torch.rsqrt(x.pow(2).mean(dim=-1, keepdim=True) + self.eps)
+
+    def forward(self, x):
+        dtype = x.dtype
+        return self.norm(x.float()).to(dtype) * self.weight
+
+
+class AttentionModule(nn.Module):
+    def __init__(self, num_heads, enable_sageattention=True):
+        super().__init__()
+        self.num_heads = num_heads
+        self.enable_sageattention = enable_sageattention
+        
+    def forward(self, q, k, v, attention_mask=None):
+        x = flash_attention(q=q, k=k, v=v, num_heads=self.num_heads, attention_mask=attention_mask, enable_sageattention=self.enable_sageattention)
+        return x
+
+
+class SelfAttention(nn.Module):
+    def __init__(self, dim: int, num_heads: int, eps: float = 1e-6, enable_sageattention: bool = True):
+        super().__init__()
+        self.dim = dim
+        self.num_heads = num_heads
+        self.head_dim = dim // num_heads
+
+        self.q = nn.Linear(dim, dim)
+        self.k = nn.Linear(dim, dim)
+        self.v = nn.Linear(dim, dim)
+        self.o = nn.Linear(dim, dim)
+        self.norm_q = RMSNorm(dim, eps=eps)
+        self.norm_k = RMSNorm(dim, eps=eps)
+        
+        self.attn = AttentionModule(self.num_heads, enable_sageattention=enable_sageattention)
+        self.local_attn_mask = None
+
+    def forward(self, x, freqs, f=None, h=None, w=None, local_num=None, topk=None,
+                train_img=False, block_id=None, kv_len=None, is_full_block=False,
+                is_stream=False, pre_cache_k=None, pre_cache_v=None, local_range = 9):
+        B, L, D = x.shape
+        if is_stream and pre_cache_k is not None and pre_cache_v is not None:
+            assert f==2, "f must be 2"
+        if is_stream and (pre_cache_k is None or pre_cache_v is None):
+            assert f==6, " start f must be 6"
+        assert L == f * h * w, "Sequence length mismatch with provided (f,h,w)."
+
+        q = self.norm_q(self.q(x))
+        k = self.norm_k(self.k(x))
+        v = self.v(x)
+        q = rope_apply(q, freqs, self.num_heads)
+        k = rope_apply(k, freqs, self.num_heads)
+
+        win = (2, 8, 8)
+        q = q.view(B, f, h, w, D)
+        k = k.view(B, f, h, w, D)
+        v = v.view(B, f, h, w, D)
+
+        q_w = WindowPartition3D.partition(q, win)
+        k_w = WindowPartition3D.partition(k, win)
+        v_w = WindowPartition3D.partition(v, win)
+
+        seqlen = f//win[0]
+        one_len = k_w.shape[0] // B // seqlen
+        if pre_cache_k is not None and pre_cache_v is not None:
+            k_w = torch.cat([pre_cache_k, k_w], dim=0)
+            v_w = torch.cat([pre_cache_v, v_w], dim=0)
+
+        block_n = q_w.shape[0] // B
+        block_s = q_w.shape[1]
+        block_n_kv = k_w.shape[0] // B
+
+        reorder_q = rearrange(q_w, '(b block_n) (block_s) d -> b (block_n block_s) d', block_n=block_n, block_s=block_s)
+        reorder_k = rearrange(k_w, '(b block_n) (block_s) d -> b (block_n block_s) d', block_n=block_n_kv, block_s=block_s)
+        reorder_v = rearrange(v_w, '(b block_n) (block_s) d -> b (block_n block_s) d', block_n=block_n_kv, block_s=block_s)
+
+        window_size = win[0]*h*w//128
+
+        if self.local_attn_mask is None or self.local_attn_mask_h!=h//8 or self.local_attn_mask_w!=w//8 or self.local_range!=local_range:
+            self.local_attn_mask = build_local_block_mask_shifted_vec_normal_slide(h//8, w//8, local_range, local_range, include_self=True, device=k_w.device)
+            self.local_attn_mask_h = h//8
+            self.local_attn_mask_w = w//8
+            self.local_range = local_range
+        attention_mask = generate_draft_block_mask(B, self.num_heads, seqlen, q_w, k_w, topk=topk, local_attn_mask=self.local_attn_mask)
+
+        x = self.attn(reorder_q, reorder_k, reorder_v, attention_mask)
+
+        cur_block_n, cur_block_s, _ = k_w.shape
+        cache_num = cur_block_n // one_len
+        if cache_num > kv_len:
+            cache_k = k_w[one_len:, :, :]
+            cache_v = v_w[one_len:, :, :]
+        else:
+            cache_k = k_w
+            cache_v = v_w
+
+        x = rearrange(x, 'b (block_n block_s) d -> (b block_n) (block_s) d', block_n=block_n, block_s=block_s)
+        x = WindowPartition3D.reverse(x, win, (f, h, w))
+        x = x.view(B, f*h*w, D)
+
+        if is_stream:
+            return self.o(x), cache_k, cache_v
+        return self.o(x)
+
+
+class CrossAttention(nn.Module):
+    """
+    仅考虑文本 context；提供持久 KV 缓存。
+    """
+    def __init__(self, dim: int, num_heads: int, eps: float = 1e-6, enable_sageattention: bool = True):
+        super().__init__()
+        self.dim = dim
+        self.num_heads = num_heads
+        self.head_dim = dim // num_heads
+
+        self.q = nn.Linear(dim, dim)
+        self.k = nn.Linear(dim, dim)
+        self.v = nn.Linear(dim, dim)
+        self.o = nn.Linear(dim, dim)
+
+        self.norm_q = RMSNorm(dim, eps=eps)
+        self.norm_k = RMSNorm(dim, eps=eps)
+
+        self.attn = AttentionModule(self.num_heads, enable_sageattention=False)
+
+        # 持久缓存
+        self.cache_k = None
+        self.cache_v = None
+
+    @torch.no_grad()
+    def init_cache(self, ctx: torch.Tensor):
+        """ctx: [B, S_ctx, dim] —— 经过 text_embedding 之后的上下文"""
+        self.cache_k = self.norm_k(self.k(ctx))
+        self.cache_v = self.v(ctx)
+
+    def clear_cache(self):
+        self.cache_k = None
+        self.cache_v = None
+
+    def forward(self, x: torch.Tensor, y: torch.Tensor, is_stream: bool = False):
+        """
+        y 即文本上下文（未做其他分支）。
+        """
+        q = self.norm_q(self.q(x))
+        assert self.cache_k is not None and self.cache_v is not None
+        k = self.cache_k
+        v = self.cache_v
+
+        x = self.attn(q, k, v)
+        return self.o(x)
+
+
+class GateModule(nn.Module):
+    def __init__(self,):
+        super().__init__()
+
+    def forward(self, x, gate, residual):
+        return x + gate * residual
+
+
+class DiTBlock(nn.Module):
+    def __init__(self, dim: int, num_heads: int, ffn_dim: int, eps: float = 1e-6, enable_sageattention: bool = True):
+        super().__init__()
+        self.dim = dim
+        self.num_heads = num_heads
+        self.ffn_dim = ffn_dim
+
+        self.self_attn = SelfAttention(dim, num_heads, eps, enable_sageattention=enable_sageattention)
+        self.cross_attn = CrossAttention(dim, num_heads, eps, enable_sageattention=False)
+
+        self.norm1 = nn.LayerNorm(dim, eps=eps, elementwise_affine=False)
+        self.norm2 = nn.LayerNorm(dim, eps=eps, elementwise_affine=False)
+        self.norm3 = nn.LayerNorm(dim, eps=eps)
+        self.ffn = nn.Sequential(nn.Linear(dim, ffn_dim), nn.GELU(
+            approximate='tanh'), nn.Linear(ffn_dim, dim))
+        self.modulation = nn.Parameter(torch.randn(1, 6, dim) / dim**0.5)
+        self.gate = GateModule()
+
+    def forward(self, x, context, t_mod, freqs, f, h, w, local_num=None, topk=None,
+                train_img=False, block_id=None, kv_len=None, is_full_block=False,
+                is_stream=False, pre_cache_k=None, pre_cache_v=None, local_range = 9):
+        shift_msa, scale_msa, gate_msa, shift_mlp, scale_mlp, gate_mlp = (
+            self.modulation.to(dtype=t_mod.dtype, device=t_mod.device) + t_mod).chunk(6, dim=1)
+        input_x = modulate(self.norm1(x), shift_msa, scale_msa)
+        self_attn_output, self_attn_cache_k, self_attn_cache_v = self.self_attn(
+            input_x, freqs, f, h, w, local_num, topk, train_img, block_id,
+            kv_len=kv_len, is_full_block=is_full_block, is_stream=is_stream,
+            pre_cache_k=pre_cache_k, pre_cache_v=pre_cache_v, local_range = local_range)
+
+        x = self.gate(x, gate_msa, self_attn_output)
+        x = x + self.cross_attn(self.norm3(x), context, is_stream=is_stream)
+        input_x = modulate(self.norm2(x), shift_mlp, scale_mlp)
+        x = self.gate(x, gate_mlp, self.ffn(input_x))
+        if is_stream:
+            return x, self_attn_cache_k, self_attn_cache_v
+        return x
+
+
+class MLP(torch.nn.Module):
+    def __init__(self, in_dim, out_dim, has_pos_emb=False):
+        super().__init__()
+        self.proj = torch.nn.Sequential(
+            nn.LayerNorm(in_dim),
+            nn.Linear(in_dim, in_dim),
+            nn.GELU(),
+            nn.Linear(in_dim, out_dim),
+            nn.LayerNorm(out_dim)
+        )
+        self.has_pos_emb = has_pos_emb
+        if has_pos_emb:
+            self.emb_pos = torch.nn.Parameter(torch.zeros((1, 514, 1280)))
+
+    def forward(self, x):
+        if self.has_pos_emb:
+            x = x + self.emb_pos.to(dtype=x.dtype, device=x.device)
+        return self.proj(x)
+
+
+class Head(nn.Module):
+    def __init__(self, dim: int, out_dim: int, patch_size: Tuple[int, int, int], eps: float):
+        super().__init__()
+        self.dim = dim
+        self.patch_size = patch_size
+        self.norm = nn.LayerNorm(dim, eps=eps, elementwise_affine=False)
+        self.head = nn.Linear(dim, out_dim * math.prod(patch_size))
+        self.modulation = nn.Parameter(torch.randn(1, 2, dim) / dim**0.5)
+
+    def forward(self, x, t_mod):
+        shift, scale = (self.modulation.to(dtype=t_mod.dtype, device=t_mod.device) + t_mod).chunk(2, dim=1)
+        x = (self.head(self.norm(x) * (1 + scale) + shift))
+        return x
+
+
+# ----------------------------
+# WanModel (no image branch) — init 时即产生 KV 缓存
+# ----------------------------
+class WanModel(torch.nn.Module):
+    def __init__(
+        self,
+        dim: int,
+        in_dim: int,
+        ffn_dim: int,
+        out_dim: int,
+        text_dim: int,
+        freq_dim: int,
+        eps: float,
+        patch_size: Tuple[int, int, int],
+        num_heads: int,
+        num_layers: int,
+        has_image_input: bool = False,
+        enable_sageattention: bool = True,
+    ):
+        super().__init__()
+        self.dim = dim
+        self.freq_dim = freq_dim
+        self.patch_size = patch_size
+
+        # patch embed
+        self.patch_embedding = nn.Conv3d(
+            in_dim, dim, kernel_size=patch_size, stride=patch_size)
+
+        # text / time embed
+        self.text_embedding = nn.Sequential(
+            nn.Linear(text_dim, dim),
+            nn.GELU(approximate='tanh'),
+            nn.Linear(dim, dim)
+        )
+        self.time_embedding = nn.Sequential(
+            nn.Linear(freq_dim, dim),
+            nn.SiLU(),
+            nn.Linear(dim, dim)
+        )
+        self.time_projection = nn.Sequential(
+            nn.SiLU(), nn.Linear(dim, dim * 6))
+
+        # blocks
+        self.blocks = nn.ModuleList([
+            DiTBlock(dim, num_heads, ffn_dim, eps, enable_sageattention=enable_sageattention)
+            for _ in range(num_layers)
+        ])
+        self.head = Head(dim, out_dim, patch_size, eps)
+
+        head_dim = dim // num_heads
+        self.freqs = precompute_freqs_cis_3d(head_dim)
+
+        self._cross_kv_initialized = False
+
+    # 可选：手动清空 / 重新初始化
+        # 可选：手动清空 / 重新初始化
+    def clear_cross_kv(self):
+        for blk in self.blocks:
+            blk.cross_attn.clear_cache()
+        self._cross_kv_initialized = False
+
+    @torch.no_grad()
+    def reinit_cross_kv(self, new_context: torch.Tensor):
+        ctx_txt = self.text_embedding(new_context)
+        for blk in self.blocks:
+            blk.cross_attn.init_cache(ctx_txt)
+        self._cross_kv_initialized = True
+
+    def patchify(self, x: torch.Tensor):
+        x = self.patch_embedding(x)
+        grid_size = x.shape[2:]
+        x = rearrange(x, 'b c f h w -> b (f h w) c').contiguous()
+        return x, grid_size  # x, grid_size: (f, h, w)
+
+    def unpatchify(self, x: torch.Tensor, grid_size: torch.Tensor):
+        return rearrange(
+            x, 'b (f h w) (x y z c) -> b c (f x) (h y) (w z)',
+            f=grid_size[0], h=grid_size[1], w=grid_size[2], 
+            x=self.patch_size[0], y=self.patch_size[1], z=self.patch_size[2]
+        )
+
+    def forward(self,
+                x: torch.Tensor,
+                timestep: torch.Tensor,
+                context: torch.Tensor,
+                use_gradient_checkpointing: bool = False,
+                use_gradient_checkpointing_offload: bool = False,
+                LQ_latents: Optional[List[torch.Tensor]] = None,
+                train_img: bool = False,
+                topk_ratio: Optional[float] = None,
+                kv_ratio: Optional[float] = None,
+                local_num: Optional[int] = None,
+                is_full_block: bool = False,
+                causal_idx: Optional[int] = None,
+                **kwargs,
+                ):
+        # time / text embeds
+        t = self.time_embedding(
+            sinusoidal_embedding_1d(self.freq_dim, timestep))
+        t_mod = self.time_projection(t).unflatten(1, (6, self.dim))
+
+        # 这里仍会嵌入 text（CrossAttention 若已有缓存会忽略它）
+        # context = self.text_embedding(context)
+
+        # 输入打补丁
+        x, (f, h, w) = self.patchify(x)
+        B = x.shape[0]
+
+        # window / masks 超参
+        win = (2, 8, 8)
+        seqlen = f//win[0]
+        if local_num is None:
+            local_random = random.random()
+            if local_random < 0.3:
+                local_num = seqlen - 3
+            elif local_random < 0.4:
+                local_num = seqlen - 4
+            elif local_random < 0.5:
+                local_num = seqlen - 2
+            else:
+                local_num = seqlen
+
+        window_size = win[0]*h*w//128
+        square_num = window_size*window_size
+        topk_ratio = 2.0
+        topk = min(max(int(square_num*topk_ratio), 1), int(square_num*seqlen)-1)
+
+        if kv_ratio is None:
+            kv_ratio = (random.uniform(0., 1.0)**2)*(local_num-2-2)+2
+        kv_len = min(max(int(window_size*kv_ratio), 1), int(window_size*seqlen)-1)
+
+        decay_ratio = random.uniform(0.7, 1.0)
+
+        # RoPE 3D
+        freqs = torch.cat([
+            self.freqs[0][:f].view(f, 1, 1, -1).expand(f, h, w, -1),
+            self.freqs[1][:h].view(1, h, 1, -1).expand(f, h, w, -1),
+            self.freqs[2][:w].view(1, 1, w, -1).expand(f, h, w, -1)
+        ], dim=-1).reshape(f * h * w, 1, -1).to(x.device)
+
+        def create_custom_forward(module):
+            def custom_forward(*inputs):
+                return module(*inputs)
+            return custom_forward
+
+        # blocks
+        for block_id, block in enumerate(self.blocks):
+            if LQ_latents is not None and block_id < len(LQ_latents):
+                x += LQ_latents[block_id]
+
+            if self.training and use_gradient_checkpointing:
+                if use_gradient_checkpointing_offload:
+                    with torch.autograd.graph.save_on_cpu():
+                        x = torch.utils.checkpoint.checkpoint(
+                            create_custom_forward(block),
+                            x, context, t_mod, freqs, f, h, w, local_num, topk,
+                            train_img, block_id, kv_len, is_full_block, False,
+                            None, None,
+                            use_reentrant=False,
+                        )
+                else:
+                    x = torch.utils.checkpoint.checkpoint(
+                        create_custom_forward(block),
+                        x, context, t_mod, freqs, f, h, w, local_num, topk,
+                        train_img, block_id, kv_len, is_full_block, False,
+                        None, None, 
+                        use_reentrant=False,
+                    )
+            else:
+                x = block(x, context, t_mod, freqs, f, h, w, local_num, topk,
+                          train_img, block_id, kv_len, is_full_block, False,
+                          None, None)
+
+        x = self.head(x, t)
+        x = self.unpatchify(x, (f, h, w))
+        return x
+
+    @staticmethod
+    def state_dict_converter():
+        return WanModelStateDictConverter()
+    
+
+# ----------------------------
+# State dict converter（保持原映射；已忽略 has_image_input 使用）
+# ----------------------------
+class WanModelStateDictConverter:
+    def __init__(self):
+        pass
+
+    def from_diffusers(self, state_dict):
+        rename_dict = {
+            "blocks.0.attn1.norm_k.weight": "blocks.0.self_attn.norm_k.weight",
+            "blocks.0.attn1.norm_q.weight": "blocks.0.self_attn.norm_q.weight",
+            "blocks.0.attn1.to_k.bias": "blocks.0.self_attn.k.bias",
+            "blocks.0.attn1.to_k.weight": "blocks.0.self_attn.k.weight",
+            "blocks.0.attn1.to_out.0.bias": "blocks.0.self_attn.o.bias",
+            "blocks.0.attn1.to_out.0.weight": "blocks.0.self_attn.o.weight",
+            "blocks.0.attn1.to_q.bias": "blocks.0.self_attn.q.bias",
+            "blocks.0.attn1.to_q.weight": "blocks.0.self_attn.q.weight",
+            "blocks.0.attn1.to_v.bias": "blocks.0.self_attn.v.bias",
+            "blocks.0.attn1.to_v.weight": "blocks.0.self_attn.v.weight",
+            "blocks.0.attn2.norm_k.weight": "blocks.0.cross_attn.norm_k.weight",
+            "blocks.0.attn2.norm_q.weight": "blocks.0.cross_attn.norm_q.weight",
+            "blocks.0.attn2.to_k.bias": "blocks.0.cross_attn.k.bias",
+            "blocks.0.attn2.to_k.weight": "blocks.0.cross_attn.k.weight",
+            "blocks.0.attn2.to_out.0.bias": "blocks.0.cross_attn.o.bias",
+            "blocks.0.attn2.to_out.0.weight": "blocks.0.cross_attn.o.weight",
+            "blocks.0.attn2.to_q.bias": "blocks.0.cross_attn.q.bias",
+            "blocks.0.attn2.to_q.weight": "blocks.0.cross_attn.q.weight",
+            "blocks.0.attn2.to_v.bias": "blocks.0.cross_attn.v.bias",
+            "blocks.0.attn2.to_v.weight": "blocks.0.cross_attn.v.weight",
+            "blocks.0.ffn.net.0.proj.bias": "blocks.0.ffn.0.bias",
+            "blocks.0.ffn.net.0.proj.weight": "blocks.0.ffn.0.weight",
+            "blocks.0.ffn.net.2.bias": "blocks.0.ffn.2.bias",
+            "blocks.0.ffn.net.2.weight": "blocks.0.ffn.2.weight",
+            "blocks.0.norm2.bias": "blocks.0.norm3.bias",
+            "blocks.0.norm2.weight": "blocks.0.norm3.weight",
+            "blocks.0.scale_shift_table": "blocks.0.modulation",
+            "condition_embedder.text_embedder.linear_1.bias": "text_embedding.0.bias",
+            "condition_embedder.text_embedder.linear_1.weight": "text_embedding.0.weight",
+            "condition_embedder.text_embedder.linear_2.bias": "text_embedding.2.bias",
+            "condition_embedder.text_embedder.linear_2.weight": "text_embedding.2.weight",
+            "condition_embedder.time_embedder.linear_1.bias": "time_embedding.0.bias",
+            "condition_embedder.time_embedder.linear_1.weight": "time_embedding.0.weight",
+            "condition_embedder.time_embedder.linear_2.bias": "time_embedding.2.bias",
+            "condition_embedder.time_embedder.linear_2.weight": "time_embedding.2.weight",
+            "condition_embedder.time_proj.bias": "time_projection.1.bias",
+            "condition_embedder.time_proj.weight": "time_projection.1.weight",
+            "patch_embedding.bias": "patch_embedding.bias",
+            "patch_embedding.weight": "patch_embedding.weight",
+            "scale_shift_table": "head.modulation",
+            "proj_out.bias": "head.head.bias",
+            "proj_out.weight": "head.head.weight",
+        }
+        state_dict_ = {}
+        for name, param in state_dict.items():
+            if name in rename_dict:
+                state_dict_[rename_dict[name]] = param
+            else:
+                name_ = ".".join(name.split(".")[:1] + ["0"] + name.split(".")[2:])
+                if name_ in rename_dict:
+                    name_ = rename_dict[name_]
+                    name_ = ".".join(name_.split(".")[:1] + [name.split(".")[1]] + name_.split(".")[2:])
+                    state_dict_[name_] = param
+        if hash_state_dict_keys(state_dict) == "cb104773c6c2cb6df4f9529ad5c60d0b":
+            config = {
+                "model_type": "t2v",
+                "patch_size": (1, 2, 2),
+                "text_len": 512,
+                "in_dim": 16,
+                "dim": 5120,
+                "ffn_dim": 13824,
+                "freq_dim": 256,
+                "text_dim": 4096,
+                "out_dim": 16,
+                "num_heads": 40,
+                "num_layers": 40,
+                "window_size": (-1, -1),
+                "qk_norm": True,
+                "cross_attn_norm": True,
+                "eps": 1e-6,
+            }
+        else:
+            config = {}
+        return state_dict_, config
+    
+    def from_civitai(self, state_dict):
+        state_dict = {name: param for name, param in state_dict.items() if not name.startswith("vace")}
+        # 保留原有哈希匹配返回的 config；实现本身不使用 has_image_input 分支
+        if hash_state_dict_keys(state_dict) == "9269f8db9040a9d860eaca435be61814":
+            config = {"has_image_input": False,"patch_size": [1, 2, 2],"in_dim": 16,"dim": 1536,"ffn_dim": 8960,"freq_dim": 256,"text_dim": 4096,"out_dim": 16,"num_heads": 12,"num_layers": 30,"eps": 1e-6}
+        elif hash_state_dict_keys(state_dict) == "aafcfd9672c3a2456dc46e1cb6e52c70":
+            config = {"has_image_input": False,"patch_size": [1, 2, 2],"in_dim": 16,"dim": 5120,"ffn_dim": 13824,"freq_dim": 256,"text_dim": 4096,"out_dim": 16,"num_heads": 40,"num_layers": 40,"eps": 1e-6}
+        elif hash_state_dict_keys(state_dict) == "6bfcfb3b342cb286ce886889d519a77e":
+            config = {"has_image_input": False,"patch_size": [1, 2, 2],"in_dim": 36,"dim": 5120,"ffn_dim": 13824,"freq_dim": 256,"text_dim": 4096,"out_dim": 16,"num_heads": 40,"num_layers": 40,"eps": 1e-6}
+        elif hash_state_dict_keys(state_dict) == "6d6ccde6845b95ad9114ab993d917893":
+            config = {"has_image_input": False,"patch_size": [1, 2, 2],"in_dim": 36,"dim": 1536,"ffn_dim": 8960,"freq_dim": 256,"text_dim": 4096,"out_dim": 16,"num_heads": 12,"num_layers": 30,"eps": 1e-6}
+        elif hash_state_dict_keys(state_dict) == "349723183fc063b2bfc10bb2835cf677":
+            config = {"has_image_input": False,"patch_size": [1, 2, 2],"in_dim": 48,"dim": 1536,"ffn_dim": 8960,"freq_dim": 256,"text_dim": 4096,"out_dim": 16,"num_heads": 12,"num_layers": 30,"eps": 1e-6}
+        elif hash_state_dict_keys(state_dict) == "efa44cddf936c70abd0ea28b6cbe946c":
+            config = {"has_image_input": False,"patch_size": [1, 2, 2],"in_dim": 48,"dim": 5120,"ffn_dim": 13824,"freq_dim": 256,"text_dim": 4096,"out_dim": 16,"num_heads": 40,"num_layers": 40,"eps": 1e-6}
+        elif hash_state_dict_keys(state_dict) == "3ef3b1f8e1dab83d5b71fd7b617f859f":
+            config = {"has_image_input": False,"patch_size": [1, 2, 2],"in_dim": 36,"dim": 5120,"ffn_dim": 13824,"freq_dim": 256,"text_dim": 4096,"out_dim": 16,"num_heads": 40,"num_layers": 40,"eps": 1e-6,"has_image_pos_emb": False}
+        else:
+            config = {}
+        return state_dict, config
+    

flashvsr_arch/models/wan_video_vae.py

@@ -0,0 +1,847 @@
+from einops import rearrange, repeat
+
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+from tqdm import tqdm
+
+CACHE_T = 2
+
+
+def check_is_instance(model, module_class):
+    if isinstance(model, module_class):
+        return True
+    if hasattr(model, "module") and isinstance(model.module, module_class):
+        return True
+    return False
+
+
+def block_causal_mask(x, block_size):
+    # params
+    b, n, s, _, device = *x.size(), x.device
+    assert s % block_size == 0
+    num_blocks = s // block_size
+
+    # build mask
+    mask = torch.zeros(b, n, s, s, dtype=torch.bool, device=device)
+    for i in range(num_blocks):
+        mask[:, :,
+             i * block_size:(i + 1) * block_size, :(i + 1) * block_size] = 1
+    return mask
+
+
+class CausalConv3d(nn.Conv3d):
+    """
+    Causal 3d convolusion.
+    """
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self._padding = (self.padding[2], self.padding[2], self.padding[1],
+                         self.padding[1], 2 * self.padding[0], 0)
+        self.padding = (0, 0, 0)
+
+    def forward(self, x, cache_x=None):
+        padding = list(self._padding)
+        if cache_x is not None and self._padding[4] > 0:
+            cache_x = cache_x.to(x.device)
+            # print('cache_x.shape', cache_x.shape, 'x.shape', x.shape)
+            x = torch.cat([cache_x, x], dim=2)
+            padding[4] -= cache_x.shape[2]
+        x = F.pad(x, padding)
+
+        return super().forward(x)
+
+
+class RMS_norm(nn.Module):
+
+    def __init__(self, dim, channel_first=True, images=True, bias=False):
+        super().__init__()
+        broadcastable_dims = (1, 1, 1) if not images else (1, 1)
+        shape = (dim, *broadcastable_dims) if channel_first else (dim,)
+
+        self.channel_first = channel_first
+        self.scale = dim**0.5
+        self.gamma = nn.Parameter(torch.ones(shape))
+        self.bias = nn.Parameter(torch.zeros(shape)) if bias else 0.
+
+    def forward(self, x):
+        return F.normalize(
+            x, dim=(1 if self.channel_first else
+                    -1)) * self.scale * self.gamma + self.bias
+
+
+class Upsample(nn.Upsample):
+
+    def forward(self, x):
+        """
+        Fix bfloat16 support for nearest neighbor interpolation.
+        """
+        return super().forward(x.float()).type_as(x)
+
+
+class Resample(nn.Module):
+
+    def __init__(self, dim, mode):
+        assert mode in ('none', 'upsample2d', 'upsample3d', 'downsample2d',
+                        'downsample3d')
+        super().__init__()
+        self.dim = dim
+        self.mode = mode
+
+        # layers
+        if mode == 'upsample2d':
+            self.resample = nn.Sequential(
+                Upsample(scale_factor=(2., 2.), mode='nearest-exact'),
+                nn.Conv2d(dim, dim // 2, 3, padding=1))
+        elif mode == 'upsample3d':
+            self.resample = nn.Sequential(
+                Upsample(scale_factor=(2., 2.), mode='nearest-exact'),
+                nn.Conv2d(dim, dim // 2, 3, padding=1))
+            self.time_conv = CausalConv3d(dim,
+                                          dim * 2, (3, 1, 1),
+                                          padding=(1, 0, 0))
+
+        elif mode == 'downsample2d':
+            self.resample = nn.Sequential(
+                nn.ZeroPad2d((0, 1, 0, 1)),
+                nn.Conv2d(dim, dim, 3, stride=(2, 2)))
+        elif mode == 'downsample3d':
+            self.resample = nn.Sequential(
+                nn.ZeroPad2d((0, 1, 0, 1)),
+                nn.Conv2d(dim, dim, 3, stride=(2, 2)))
+            self.time_conv = CausalConv3d(dim,
+                                          dim, (3, 1, 1),
+                                          stride=(2, 1, 1),
+                                          padding=(0, 0, 0))
+
+        else:
+            self.resample = nn.Identity()
+
+    def forward(self, x, feat_cache=None, feat_idx=[0]):
+        b, c, t, h, w = x.size()
+        if self.mode == 'upsample3d':
+            if feat_cache is not None:
+                idx = feat_idx[0]
+                if feat_cache[idx] is None:
+                    feat_cache[idx] = 'Rep'
+                    feat_idx[0] += 1
+                else:
+
+                    cache_x = x[:, :, -CACHE_T:, :, :].clone()
+                    if cache_x.shape[2] < 2 and feat_cache[
+                            idx] is not None and feat_cache[idx] != 'Rep':
+                        # cache last frame of last two chunk
+                        cache_x = torch.cat([
+                            feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(
+                                cache_x.device), cache_x
+                        ],
+                                            dim=2)
+                    if cache_x.shape[2] < 2 and feat_cache[
+                            idx] is not None and feat_cache[idx] == 'Rep':
+                        cache_x = torch.cat([
+                            torch.zeros_like(cache_x).to(cache_x.device),
+                            cache_x
+                        ],
+                                            dim=2)
+                    if feat_cache[idx] == 'Rep':
+                        x = self.time_conv(x)
+                    else:
+                        x = self.time_conv(x, feat_cache[idx])
+                    feat_cache[idx] = cache_x
+                    feat_idx[0] += 1
+
+                    x = x.reshape(b, 2, c, t, h, w)
+                    x = torch.stack((x[:, 0, :, :, :, :], x[:, 1, :, :, :, :]),
+                                    3)
+                    x = x.reshape(b, c, t * 2, h, w)
+        t = x.shape[2]
+        x = rearrange(x, 'b c t h w -> (b t) c h w')
+        x = self.resample(x)
+        x = rearrange(x, '(b t) c h w -> b c t h w', t=t)
+
+        if self.mode == 'downsample3d':
+            if feat_cache is not None:
+                idx = feat_idx[0]
+                if feat_cache[idx] is None:
+                    feat_cache[idx] = x.clone()
+                    feat_idx[0] += 1
+                else:
+                    cache_x = x[:, :, -1:, :, :].clone()
+                    x = self.time_conv(
+                        torch.cat([feat_cache[idx][:, :, -1:, :, :], x], 2))
+                    feat_cache[idx] = cache_x
+                    feat_idx[0] += 1
+        return x
+
+    def init_weight(self, conv):
+        conv_weight = conv.weight
+        nn.init.zeros_(conv_weight)
+        c1, c2, t, h, w = conv_weight.size()
+        one_matrix = torch.eye(c1, c2)
+        init_matrix = one_matrix
+        nn.init.zeros_(conv_weight)
+        conv_weight.data[:, :, 1, 0, 0] = init_matrix
+        conv.weight.data.copy_(conv_weight)
+        nn.init.zeros_(conv.bias.data)
+
+    def init_weight2(self, conv):
+        conv_weight = conv.weight.data
+        nn.init.zeros_(conv_weight)
+        c1, c2, t, h, w = conv_weight.size()
+        init_matrix = torch.eye(c1 // 2, c2)
+        conv_weight[:c1 // 2, :, -1, 0, 0] = init_matrix
+        conv_weight[c1 // 2:, :, -1, 0, 0] = init_matrix
+        conv.weight.data.copy_(conv_weight)
+        nn.init.zeros_(conv.bias.data)
+
+
+class ResidualBlock(nn.Module):
+
+    def __init__(self, in_dim, out_dim, dropout=0.0):
+        super().__init__()
+        self.in_dim = in_dim
+        self.out_dim = out_dim
+
+        # layers
+        self.residual = nn.Sequential(
+            RMS_norm(in_dim, images=False), nn.SiLU(),
+            CausalConv3d(in_dim, out_dim, 3, padding=1),
+            RMS_norm(out_dim, images=False), nn.SiLU(), nn.Dropout(dropout),
+            CausalConv3d(out_dim, out_dim, 3, padding=1))
+        self.shortcut = CausalConv3d(in_dim, out_dim, 1) \
+            if in_dim != out_dim else nn.Identity()
+
+    def forward(self, x, feat_cache=None, feat_idx=[0]):
+        h = self.shortcut(x)
+        for layer in self.residual:
+            if check_is_instance(layer, CausalConv3d) and feat_cache is not None:
+                idx = feat_idx[0]
+                cache_x = x[:, :, -CACHE_T:, :, :].clone()
+                if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
+                    # cache last frame of last two chunk
+                    cache_x = torch.cat([
+                        feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(
+                            cache_x.device), cache_x
+                    ],
+                                        dim=2)
+                x = layer(x, feat_cache[idx])
+                feat_cache[idx] = cache_x
+                feat_idx[0] += 1
+            else:
+                x = layer(x)
+        return x + h
+
+
+class AttentionBlock(nn.Module):
+    """
+    Causal self-attention with a single head.
+    """
+
+    def __init__(self, dim):
+        super().__init__()
+        self.dim = dim
+
+        # layers
+        self.norm = RMS_norm(dim)
+        self.to_qkv = nn.Conv2d(dim, dim * 3, 1)
+        self.proj = nn.Conv2d(dim, dim, 1)
+
+        # zero out the last layer params
+        nn.init.zeros_(self.proj.weight)
+
+    def forward(self, x):
+        identity = x
+        b, c, t, h, w = x.size()
+        x = rearrange(x, 'b c t h w -> (b t) c h w')
+        x = self.norm(x)
+        # compute query, key, value
+        q, k, v = self.to_qkv(x).reshape(b * t, 1, c * 3, -1).permute(
+            0, 1, 3, 2).contiguous().chunk(3, dim=-1)
+
+        # apply attention
+        x = F.scaled_dot_product_attention(
+            q,
+            k,
+            v,
+            #attn_mask=block_causal_mask(q, block_size=h * w)
+        )
+        x = x.squeeze(1).permute(0, 2, 1).reshape(b * t, c, h, w)
+
+        # output
+        x = self.proj(x)
+        x = rearrange(x, '(b t) c h w-> b c t h w', t=t)
+        return x + identity
+
+
+class Encoder3d(nn.Module):
+
+    def __init__(self,
+                 dim=128,
+                 z_dim=4,
+                 dim_mult=[1, 2, 4, 4],
+                 num_res_blocks=2,
+                 attn_scales=[],
+                 temperal_downsample=[True, True, False],
+                 dropout=0.0):
+        super().__init__()
+        self.dim = dim
+        self.z_dim = z_dim
+        self.dim_mult = dim_mult
+        self.num_res_blocks = num_res_blocks
+        self.attn_scales = attn_scales
+        self.temperal_downsample = temperal_downsample
+
+        # dimensions
+        dims = [dim * u for u in [1] + dim_mult]
+        scale = 1.0
+
+        # init block
+        self.conv1 = CausalConv3d(3, dims[0], 3, padding=1)
+
+        # downsample blocks
+        downsamples = []
+        for i, (in_dim, out_dim) in enumerate(zip(dims[:-1], dims[1:])):
+            # residual (+attention) blocks
+            for _ in range(num_res_blocks):
+                downsamples.append(ResidualBlock(in_dim, out_dim, dropout))
+                if scale in attn_scales:
+                    downsamples.append(AttentionBlock(out_dim))
+                in_dim = out_dim
+
+            # downsample block
+            if i != len(dim_mult) - 1:
+                mode = 'downsample3d' if temperal_downsample[
+                    i] else 'downsample2d'
+                downsamples.append(Resample(out_dim, mode=mode))
+                scale /= 2.0
+        self.downsamples = nn.Sequential(*downsamples)
+
+        # middle blocks
+        self.middle = nn.Sequential(ResidualBlock(out_dim, out_dim, dropout),
+                                    AttentionBlock(out_dim),
+                                    ResidualBlock(out_dim, out_dim, dropout))
+
+        # output blocks
+        self.head = nn.Sequential(RMS_norm(out_dim, images=False), nn.SiLU(),
+                                  CausalConv3d(out_dim, z_dim, 3, padding=1))
+
+    def forward(self, x, feat_cache=None, feat_idx=[0]):
+        if feat_cache is not None:
+            idx = feat_idx[0]
+            cache_x = x[:, :, -CACHE_T:, :, :].clone()
+            if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
+                # cache last frame of last two chunk
+                cache_x = torch.cat([
+                    feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(
+                        cache_x.device), cache_x
+                ],
+                                    dim=2)
+            x = self.conv1(x, feat_cache[idx])
+            feat_cache[idx] = cache_x
+            feat_idx[0] += 1
+        else:
+            x = self.conv1(x)
+
+        ## downsamples
+        for layer in self.downsamples:
+            if feat_cache is not None:
+                x = layer(x, feat_cache, feat_idx)
+            else:
+                x = layer(x)
+
+        ## middle
+        for layer in self.middle:
+            if check_is_instance(layer, ResidualBlock) and feat_cache is not None:
+                x = layer(x, feat_cache, feat_idx)
+            else:
+                x = layer(x)
+
+        ## head
+        for layer in self.head:
+            if check_is_instance(layer, CausalConv3d) and feat_cache is not None:
+                idx = feat_idx[0]
+                cache_x = x[:, :, -CACHE_T:, :, :].clone()
+                if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
+                    # cache last frame of last two chunk
+                    cache_x = torch.cat([
+                        feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(
+                            cache_x.device), cache_x
+                    ],
+                                        dim=2)
+                x = layer(x, feat_cache[idx])
+                feat_cache[idx] = cache_x
+                feat_idx[0] += 1
+            else:
+                x = layer(x)
+        return x
+
+
+class Decoder3d(nn.Module):
+
+    def __init__(self,
+                 dim=128,
+                 z_dim=4,
+                 dim_mult=[1, 2, 4, 4],
+                 num_res_blocks=2,
+                 attn_scales=[],
+                 temperal_upsample=[False, True, True],
+                 dropout=0.0):
+        super().__init__()
+        self.dim = dim
+        self.z_dim = z_dim
+        self.dim_mult = dim_mult
+        self.num_res_blocks = num_res_blocks
+        self.attn_scales = attn_scales
+        self.temperal_upsample = temperal_upsample
+
+        # dimensions
+        dims = [dim * u for u in [dim_mult[-1]] + dim_mult[::-1]]
+        scale = 1.0 / 2**(len(dim_mult) - 2)
+
+        # init block
+        self.conv1 = CausalConv3d(z_dim, dims[0], 3, padding=1)
+
+        # middle blocks
+        self.middle = nn.Sequential(ResidualBlock(dims[0], dims[0], dropout),
+                                    AttentionBlock(dims[0]),
+                                    ResidualBlock(dims[0], dims[0], dropout))
+
+        # upsample blocks
+        upsamples = []
+        for i, (in_dim, out_dim) in enumerate(zip(dims[:-1], dims[1:])):
+            # residual (+attention) blocks
+            if i == 1 or i == 2 or i == 3:
+                in_dim = in_dim // 2
+            for _ in range(num_res_blocks + 1):
+                upsamples.append(ResidualBlock(in_dim, out_dim, dropout))
+                if scale in attn_scales:
+                    upsamples.append(AttentionBlock(out_dim))
+                in_dim = out_dim
+
+            # upsample block
+            if i != len(dim_mult) - 1:
+                mode = 'upsample3d' if temperal_upsample[i] else 'upsample2d'
+                upsamples.append(Resample(out_dim, mode=mode))
+                scale *= 2.0
+        self.upsamples = nn.Sequential(*upsamples)
+
+        # output blocks
+        self.head = nn.Sequential(RMS_norm(out_dim, images=False), nn.SiLU(),
+                                  CausalConv3d(out_dim, 3, 3, padding=1))
+
+    def forward(self, x, feat_cache=None, feat_idx=[0]):
+        ## conv1
+        if feat_cache is not None:
+            idx = feat_idx[0]
+            cache_x = x[:, :, -CACHE_T:, :, :].clone()
+            if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
+                # cache last frame of last two chunk
+                cache_x = torch.cat([
+                    feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(
+                        cache_x.device), cache_x
+                ],
+                                    dim=2)
+            x = self.conv1(x, feat_cache[idx])
+            feat_cache[idx] = cache_x
+            feat_idx[0] += 1
+        else:
+            x = self.conv1(x)
+
+        ## middle
+        for layer in self.middle:
+            if check_is_instance(layer, ResidualBlock) and feat_cache is not None:
+                x = layer(x, feat_cache, feat_idx)
+            else:
+                x = layer(x)
+
+        ## upsamples
+        for layer in self.upsamples:
+            if feat_cache is not None:
+                x = layer(x, feat_cache, feat_idx)
+            else:
+                x = layer(x)
+
+        ## head
+        for layer in self.head:
+            if check_is_instance(layer, CausalConv3d) and feat_cache is not None:
+                idx = feat_idx[0]
+                cache_x = x[:, :, -CACHE_T:, :, :].clone()
+                if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
+                    # cache last frame of last two chunk
+                    cache_x = torch.cat([
+                        feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(
+                            cache_x.device), cache_x
+                    ],
+                                        dim=2)
+                x = layer(x, feat_cache[idx])
+                feat_cache[idx] = cache_x
+                feat_idx[0] += 1
+            else:
+                x = layer(x)
+        return x
+
+
+def count_conv3d(model):
+    count = 0
+    for m in model.modules():
+        if check_is_instance(m, CausalConv3d):
+            count += 1
+    return count
+
+
+class VideoVAE_(nn.Module):
+
+    def __init__(self,
+                 dim=96,
+                 z_dim=16,
+                 dim_mult=[1, 2, 4, 4],
+                 num_res_blocks=2,
+                 attn_scales=[],
+                 temperal_downsample=[False, True, True],
+                 dropout=0.0):
+        super().__init__()
+        self.dim = dim
+        self.z_dim = z_dim
+        self.dim_mult = dim_mult
+        self.num_res_blocks = num_res_blocks
+        self.attn_scales = attn_scales
+        self.temperal_downsample = temperal_downsample
+        self.temperal_upsample = temperal_downsample[::-1]
+
+        # modules
+        self.encoder = Encoder3d(dim, z_dim * 2, dim_mult, num_res_blocks,
+                                 attn_scales, self.temperal_downsample, dropout)
+        self.conv1 = CausalConv3d(z_dim * 2, z_dim * 2, 1)
+        self.conv2 = CausalConv3d(z_dim, z_dim, 1)
+        self.decoder = Decoder3d(dim, z_dim, dim_mult, num_res_blocks,
+                                 attn_scales, self.temperal_upsample, dropout)
+
+    def forward(self, x):
+        mu, log_var = self.encode(x)
+        z = self.reparameterize(mu, log_var)
+        x_recon = self.decode(z)
+        return x_recon, mu, log_var
+
+    def encode(self, x, scale):
+        self.clear_cache()
+        ## cache
+        t = x.shape[2]
+        iter_ = 1 + (t - 1) // 4
+
+        for i in range(iter_):
+            self._enc_conv_idx = [0]
+            if i == 0:
+                out = self.encoder(x[:, :, :1, :, :],
+                                   feat_cache=self._enc_feat_map,
+                                   feat_idx=self._enc_conv_idx)
+            else:
+                out_ = self.encoder(x[:, :, 1 + 4 * (i - 1):1 + 4 * i, :, :],
+                                    feat_cache=self._enc_feat_map,
+                                    feat_idx=self._enc_conv_idx)
+                out = torch.cat([out, out_], 2)
+        mu, log_var = self.conv1(out).chunk(2, dim=1)
+        if isinstance(scale[0], torch.Tensor):
+            scale = [s.to(dtype=mu.dtype, device=mu.device) for s in scale]
+            mu = (mu - scale[0].view(1, self.z_dim, 1, 1, 1)) * scale[1].view(
+                1, self.z_dim, 1, 1, 1)
+        else:
+            scale = scale.to(dtype=mu.dtype, device=mu.device)
+            mu = (mu - scale[0]) * scale[1]
+        return mu
+
+    def decode(self, z, scale):
+        self.clear_cache()
+        # z: [b,c,t,h,w]
+        if isinstance(scale[0], torch.Tensor):
+            scale = [s.to(dtype=z.dtype, device=z.device) for s in scale]
+            z = z / scale[1].view(1, self.z_dim, 1, 1, 1) + scale[0].view(
+                1, self.z_dim, 1, 1, 1)
+        else:
+            scale = scale.to(dtype=z.dtype, device=z.device)
+            z = z / scale[1] + scale[0]
+        iter_ = z.shape[2]
+        x = self.conv2(z)
+        for i in range(iter_):
+            self._conv_idx = [0]
+            if i == 0:
+                out = self.decoder(x[:, :, i:i + 1, :, :],
+                                   feat_cache=self._feat_map,
+                                   feat_idx=self._conv_idx)
+            else:
+                out_ = self.decoder(x[:, :, i:i + 1, :, :],
+                                    feat_cache=self._feat_map,
+                                    feat_idx=self._conv_idx)
+                out = torch.cat([out, out_], 2) # may add tensor offload
+        return out
+
+    
+    def stream_decode(self, z, scale):
+        # self.clear_cache()
+        # z: [b,c,t,h,w]
+        if isinstance(scale[0], torch.Tensor):
+            scale = [s.to(dtype=z.dtype, device=z.device) for s in scale]
+            z = z / scale[1].view(1, self.z_dim, 1, 1, 1) + scale[0].view(
+                1, self.z_dim, 1, 1, 1)
+        else:
+            scale = scale.to(dtype=z.dtype, device=z.device)
+            z = z / scale[1] + scale[0]
+        iter_ = z.shape[2]
+        x = self.conv2(z)
+        for i in range(iter_):
+            self._conv_idx = [0]
+            if i == 0:
+                out = self.decoder(x[:, :, i:i + 1, :, :],
+                                   feat_cache=self._feat_map,
+                                   feat_idx=self._conv_idx)
+            else:
+                out_ = self.decoder(x[:, :, i:i + 1, :, :],
+                                    feat_cache=self._feat_map,
+                                    feat_idx=self._conv_idx)
+                out = torch.cat([out, out_], 2) # may add tensor offload
+        return out
+
+    def reparameterize(self, mu, log_var):
+        std = torch.exp(0.5 * log_var)
+        eps = torch.randn_like(std)
+        return eps * std + mu
+
+    def sample(self, imgs, deterministic=False):
+        mu, log_var = self.encode(imgs)
+        if deterministic:
+            return mu
+        std = torch.exp(0.5 * log_var.clamp(-30.0, 20.0))
+        return mu + std * torch.randn_like(std)
+
+    def clear_cache(self):
+        self._conv_num = count_conv3d(self.decoder)
+        self._conv_idx = [0]
+        self._feat_map = [None] * self._conv_num
+        # print('self._feat_map', len(self._feat_map))
+        # cache encode
+        if self.encoder is not None:
+            self._enc_conv_num = count_conv3d(self.encoder)
+            self._enc_conv_idx = [0]
+            self._enc_feat_map = [None] * self._enc_conv_num
+        # print('self._enc_feat_map', len(self._enc_feat_map))
+
+
+class WanVideoVAE(nn.Module):
+
+    def __init__(self, z_dim=16, dim=96):
+        super().__init__()
+
+        mean = [
+            -0.7571, -0.7089, -0.9113, 0.1075, -0.1745, 0.9653, -0.1517, 1.5508,
+            0.4134, -0.0715, 0.5517, -0.3632, -0.1922, -0.9497, 0.2503, -0.2921
+        ]
+        std = [
+            2.8184, 1.4541, 2.3275, 2.6558, 1.2196, 1.7708, 2.6052, 2.0743,
+            3.2687, 2.1526, 2.8652, 1.5579, 1.6382, 1.1253, 2.8251, 1.9160
+        ]
+        self.mean = torch.tensor(mean)
+        self.std = torch.tensor(std)
+        self.scale = [self.mean, 1.0 / self.std]
+
+        # init model
+        self.model = VideoVAE_(z_dim=z_dim, dim = dim).eval().requires_grad_(False)
+        self.upsampling_factor = 8
+
+
+    def build_1d_mask(self, length, left_bound, right_bound, border_width):
+        x = torch.ones((length,))
+        if not left_bound:
+            x[:border_width] = (torch.arange(border_width) + 1) / border_width
+        if not right_bound:
+            x[-border_width:] = torch.flip((torch.arange(border_width) + 1) / border_width, dims=(0,))
+        return x
+
+
+    def build_mask(self, data, is_bound, border_width):
+        _, _, _, H, W = data.shape
+        h = self.build_1d_mask(H, is_bound[0], is_bound[1], border_width[0])
+        w = self.build_1d_mask(W, is_bound[2], is_bound[3], border_width[1])
+
+        h = repeat(h, "H -> H W", H=H, W=W)
+        w = repeat(w, "W -> H W", H=H, W=W)
+
+        mask = torch.stack([h, w]).min(dim=0).values
+        mask = rearrange(mask, "H W -> 1 1 1 H W")
+        return mask
+
+
+    def tiled_decode(self, hidden_states, device, tile_size, tile_stride):
+        _, _, T, H, W = hidden_states.shape
+        size_h, size_w = tile_size
+        stride_h, stride_w = tile_stride
+
+        # Split tasks
+        tasks = []
+        for h in range(0, H, stride_h):
+            if (h-stride_h >= 0 and h-stride_h+size_h >= H): continue
+            for w in range(0, W, stride_w):
+                if (w-stride_w >= 0 and w-stride_w+size_w >= W): continue
+                h_, w_ = h + size_h, w + size_w
+                tasks.append((h, h_, w, w_))
+
+        data_device = "cpu"
+        computation_device = device
+
+        out_T = T * 4 - 3
+        weight = torch.zeros((1, 1, out_T, H * self.upsampling_factor, W * self.upsampling_factor), dtype=hidden_states.dtype, device=data_device)
+        values = torch.zeros((1, 3, out_T, H * self.upsampling_factor, W * self.upsampling_factor), dtype=hidden_states.dtype, device=data_device)
+
+        for h, h_, w, w_ in tqdm(tasks, desc="VAE decoding"):
+            hidden_states_batch = hidden_states[:, :, :, h:h_, w:w_].to(computation_device)
+            hidden_states_batch = self.model.decode(hidden_states_batch, self.scale).to(data_device)
+
+            mask = self.build_mask(
+                hidden_states_batch,
+                is_bound=(h==0, h_>=H, w==0, w_>=W),
+                border_width=((size_h - stride_h) * self.upsampling_factor, (size_w - stride_w) * self.upsampling_factor)
+            ).to(dtype=hidden_states.dtype, device=data_device)
+
+            target_h = h * self.upsampling_factor
+            target_w = w * self.upsampling_factor
+            values[
+                :,
+                :,
+                :,
+                target_h:target_h + hidden_states_batch.shape[3],
+                target_w:target_w + hidden_states_batch.shape[4],
+            ] += hidden_states_batch * mask
+            weight[
+                :,
+                :,
+                :,
+                target_h: target_h + hidden_states_batch.shape[3],
+                target_w: target_w + hidden_states_batch.shape[4],
+            ] += mask
+        values = values / weight
+        values = values.clamp_(-1, 1)
+        return values
+
+
+    def tiled_encode(self, video, device, tile_size, tile_stride):
+        _, _, T, H, W = video.shape
+        size_h, size_w = tile_size
+        stride_h, stride_w = tile_stride
+
+        # Split tasks
+        tasks = []
+        for h in range(0, H, stride_h):
+            if (h-stride_h >= 0 and h-stride_h+size_h >= H): continue
+            for w in range(0, W, stride_w):
+                if (w-stride_w >= 0 and w-stride_w+size_w >= W): continue
+                h_, w_ = h + size_h, w + size_w
+                tasks.append((h, h_, w, w_))
+
+        data_device = "cpu"
+        computation_device = device
+
+        out_T = (T + 3) // 4
+        weight = torch.zeros((1, 1, out_T, H // self.upsampling_factor, W // self.upsampling_factor), dtype=video.dtype, device=data_device)
+        values = torch.zeros((1, 16, out_T, H // self.upsampling_factor, W // self.upsampling_factor), dtype=video.dtype, device=data_device)
+
+        for h, h_, w, w_ in tqdm(tasks, desc="VAE encoding"):
+            hidden_states_batch = video[:, :, :, h:h_, w:w_].to(computation_device)
+            hidden_states_batch = self.model.encode(hidden_states_batch, self.scale).to(data_device)
+
+            mask = self.build_mask(
+                hidden_states_batch,
+                is_bound=(h==0, h_>=H, w==0, w_>=W),
+                border_width=((size_h - stride_h) // self.upsampling_factor, (size_w - stride_w) // self.upsampling_factor)
+            ).to(dtype=video.dtype, device=data_device)
+
+            target_h = h // self.upsampling_factor
+            target_w = w // self.upsampling_factor
+            values[
+                :,
+                :,
+                :,
+                target_h:target_h + hidden_states_batch.shape[3],
+                target_w:target_w + hidden_states_batch.shape[4],
+            ] += hidden_states_batch * mask
+            weight[
+                :,
+                :,
+                :,
+                target_h: target_h + hidden_states_batch.shape[3],
+                target_w: target_w + hidden_states_batch.shape[4],
+            ] += mask
+        values = values / weight
+        return values
+
+
+    def single_encode(self, video, device):
+        video = video.to(device)
+        x = self.model.encode(video, self.scale)
+        return x
+
+
+    def single_decode(self, hidden_state, device):
+        hidden_state = hidden_state.to(device)
+        video = self.model.decode(hidden_state, self.scale)
+        return video.clamp_(-1, 1)
+
+
+    def encode(self, videos, device, tiled=False, tile_size=(34, 34), tile_stride=(18, 16)):
+
+        videos = [video.to("cpu") for video in videos]
+        hidden_states = []
+        for video in videos:
+            video = video.unsqueeze(0)
+            if tiled:
+                tile_size = (tile_size[0] * 8, tile_size[1] * 8)
+                tile_stride = (tile_stride[0] * 8, tile_stride[1] * 8)
+                hidden_state = self.tiled_encode(video, device, tile_size, tile_stride)
+            else:
+                hidden_state = self.single_encode(video, device)
+            hidden_state = hidden_state.squeeze(0)
+            hidden_states.append(hidden_state)
+        hidden_states = torch.stack(hidden_states)
+        return hidden_states
+
+
+    def decode(self, hidden_states, device, tiled=False, tile_size=(34, 34), tile_stride=(18, 16)):
+        hidden_states = [hidden_state.to("cpu") for hidden_state in hidden_states]
+        videos = []
+        for hidden_state in hidden_states:
+            hidden_state = hidden_state.unsqueeze(0)
+            if tiled:
+                video = self.tiled_decode(hidden_state, device, tile_size, tile_stride)
+            else:
+                video = self.single_decode(hidden_state, device)
+            video = video.squeeze(0)
+            videos.append(video)
+        videos = torch.stack(videos)
+        return videos
+
+    def clear_cache(self):
+        self.model.clear_cache()
+
+    def stream_decode(self, hidden_states, tiled=False, tile_size=(34, 34), tile_stride=(18, 16)):
+        hidden_states = [hidden_state for hidden_state in hidden_states]
+        assert len(hidden_states) == 1
+        hidden_state = hidden_states[0]
+        video = self.model.stream_decode(hidden_state, self.scale)
+        return video
+
+
+    @staticmethod
+    def state_dict_converter():
+        return WanVideoVAEStateDictConverter()
+
+
+class WanVideoVAEStateDictConverter:
+
+    def __init__(self):
+        pass
+
+    def from_civitai(self, state_dict):
+        state_dict_ = {}
+        if 'model_state' in state_dict:
+            state_dict = state_dict['model_state']
+        for name in state_dict:
+            state_dict_['model.' + name] = state_dict[name]
+        return state_dict_