Support Lightricks LTX-Video model.

comfy/ldm/lightricks/vae/causal_video_autoencoder.py

@@ -0,0 +1,698 @@
+import torch
+from torch import nn
+from functools import partial
+import math
+from einops import rearrange
+from typing import Any, Mapping, Optional, Tuple, Union, List
+from .conv_nd_factory import make_conv_nd, make_linear_nd
+from .pixel_norm import PixelNorm
+
+
+class Encoder(nn.Module):
+    r"""
+    The `Encoder` layer of a variational autoencoder that encodes its input into a latent representation.
+
+    Args:
+        dims (`int` or `Tuple[int, int]`, *optional*, defaults to 3):
+            The number of dimensions to use in convolutions.
+        in_channels (`int`, *optional*, defaults to 3):
+            The number of input channels.
+        out_channels (`int`, *optional*, defaults to 3):
+            The number of output channels.
+        blocks (`List[Tuple[str, int]]`, *optional*, defaults to `[("res_x", 1)]`):
+            The blocks to use. Each block is a tuple of the block name and the number of layers.
+        base_channels (`int`, *optional*, defaults to 128):
+            The number of output channels for the first convolutional layer.
+        norm_num_groups (`int`, *optional*, defaults to 32):
+            The number of groups for normalization.
+        patch_size (`int`, *optional*, defaults to 1):
+            The patch size to use. Should be a power of 2.
+        norm_layer (`str`, *optional*, defaults to `group_norm`):
+            The normalization layer to use. Can be either `group_norm` or `pixel_norm`.
+        latent_log_var (`str`, *optional*, defaults to `per_channel`):
+            The number of channels for the log variance. Can be either `per_channel`, `uniform`, or `none`.
+    """
+
+    def __init__(
+        self,
+        dims: Union[int, Tuple[int, int]] = 3,
+        in_channels: int = 3,
+        out_channels: int = 3,
+        blocks=[("res_x", 1)],
+        base_channels: int = 128,
+        norm_num_groups: int = 32,
+        patch_size: Union[int, Tuple[int]] = 1,
+        norm_layer: str = "group_norm",  # group_norm, pixel_norm
+        latent_log_var: str = "per_channel",
+    ):
+        super().__init__()
+        self.patch_size = patch_size
+        self.norm_layer = norm_layer
+        self.latent_channels = out_channels
+        self.latent_log_var = latent_log_var
+        self.blocks_desc = blocks
+
+        in_channels = in_channels * patch_size**2
+        output_channel = base_channels
+
+        self.conv_in = make_conv_nd(
+            dims=dims,
+            in_channels=in_channels,
+            out_channels=output_channel,
+            kernel_size=3,
+            stride=1,
+            padding=1,
+            causal=True,
+        )
+
+        self.down_blocks = nn.ModuleList([])
+
+        for block_name, block_params in blocks:
+            input_channel = output_channel
+            if isinstance(block_params, int):
+                block_params = {"num_layers": block_params}
+
+            if block_name == "res_x":
+                block = UNetMidBlock3D(
+                    dims=dims,
+                    in_channels=input_channel,
+                    num_layers=block_params["num_layers"],
+                    resnet_eps=1e-6,
+                    resnet_groups=norm_num_groups,
+                    norm_layer=norm_layer,
+                )
+            elif block_name == "res_x_y":
+                output_channel = block_params.get("multiplier", 2) * output_channel
+                block = ResnetBlock3D(
+                    dims=dims,
+                    in_channels=input_channel,
+                    out_channels=output_channel,
+                    eps=1e-6,
+                    groups=norm_num_groups,
+                    norm_layer=norm_layer,
+                )
+            elif block_name == "compress_time":
+                block = make_conv_nd(
+                    dims=dims,
+                    in_channels=input_channel,
+                    out_channels=output_channel,
+                    kernel_size=3,
+                    stride=(2, 1, 1),
+                    causal=True,
+                )
+            elif block_name == "compress_space":
+                block = make_conv_nd(
+                    dims=dims,
+                    in_channels=input_channel,
+                    out_channels=output_channel,
+                    kernel_size=3,
+                    stride=(1, 2, 2),
+                    causal=True,
+                )
+            elif block_name == "compress_all":
+                block = make_conv_nd(
+                    dims=dims,
+                    in_channels=input_channel,
+                    out_channels=output_channel,
+                    kernel_size=3,
+                    stride=(2, 2, 2),
+                    causal=True,
+                )
+            elif block_name == "compress_all_x_y":
+                output_channel = block_params.get("multiplier", 2) * output_channel
+                block = make_conv_nd(
+                    dims=dims,
+                    in_channels=input_channel,
+                    out_channels=output_channel,
+                    kernel_size=3,
+                    stride=(2, 2, 2),
+                    causal=True,
+                )
+            else:
+                raise ValueError(f"unknown block: {block_name}")
+
+            self.down_blocks.append(block)
+
+        # out
+        if norm_layer == "group_norm":
+            self.conv_norm_out = nn.GroupNorm(
+                num_channels=output_channel, num_groups=norm_num_groups, eps=1e-6
+            )
+        elif norm_layer == "pixel_norm":
+            self.conv_norm_out = PixelNorm()
+        elif norm_layer == "layer_norm":
+            self.conv_norm_out = LayerNorm(output_channel, eps=1e-6)
+
+        self.conv_act = nn.SiLU()
+
+        conv_out_channels = out_channels
+        if latent_log_var == "per_channel":
+            conv_out_channels *= 2
+        elif latent_log_var == "uniform":
+            conv_out_channels += 1
+        elif latent_log_var != "none":
+            raise ValueError(f"Invalid latent_log_var: {latent_log_var}")
+        self.conv_out = make_conv_nd(
+            dims, output_channel, conv_out_channels, 3, padding=1, causal=True
+        )
+
+        self.gradient_checkpointing = False
+
+    def forward(self, sample: torch.FloatTensor) -> torch.FloatTensor:
+        r"""The forward method of the `Encoder` class."""
+
+        sample = patchify(sample, patch_size_hw=self.patch_size, patch_size_t=1)
+        sample = self.conv_in(sample)
+
+        checkpoint_fn = (
+            partial(torch.utils.checkpoint.checkpoint, use_reentrant=False)
+            if self.gradient_checkpointing and self.training
+            else lambda x: x
+        )
+
+        for down_block in self.down_blocks:
+            sample = checkpoint_fn(down_block)(sample)
+
+        sample = self.conv_norm_out(sample)
+        sample = self.conv_act(sample)
+        sample = self.conv_out(sample)
+
+        if self.latent_log_var == "uniform":
+            last_channel = sample[:, -1:, ...]
+            num_dims = sample.dim()
+
+            if num_dims == 4:
+                # For shape (B, C, H, W)
+                repeated_last_channel = last_channel.repeat(
+                    1, sample.shape[1] - 2, 1, 1
+                )
+                sample = torch.cat([sample, repeated_last_channel], dim=1)
+            elif num_dims == 5:
+                # For shape (B, C, F, H, W)
+                repeated_last_channel = last_channel.repeat(
+                    1, sample.shape[1] - 2, 1, 1, 1
+                )
+                sample = torch.cat([sample, repeated_last_channel], dim=1)
+            else:
+                raise ValueError(f"Invalid input shape: {sample.shape}")
+
+        return sample
+
+
+class Decoder(nn.Module):
+    r"""
+    The `Decoder` layer of a variational autoencoder that decodes its latent representation into an output sample.
+
+    Args:
+        dims (`int` or `Tuple[int, int]`, *optional*, defaults to 3):
+            The number of dimensions to use in convolutions.
+        in_channels (`int`, *optional*, defaults to 3):
+            The number of input channels.
+        out_channels (`int`, *optional*, defaults to 3):
+            The number of output channels.
+        blocks (`List[Tuple[str, int]]`, *optional*, defaults to `[("res_x", 1)]`):
+            The blocks to use. Each block is a tuple of the block name and the number of layers.
+        base_channels (`int`, *optional*, defaults to 128):
+            The number of output channels for the first convolutional layer.
+        norm_num_groups (`int`, *optional*, defaults to 32):
+            The number of groups for normalization.
+        patch_size (`int`, *optional*, defaults to 1):
+            The patch size to use. Should be a power of 2.
+        norm_layer (`str`, *optional*, defaults to `group_norm`):
+            The normalization layer to use. Can be either `group_norm` or `pixel_norm`.
+        causal (`bool`, *optional*, defaults to `True`):
+            Whether to use causal convolutions or not.
+    """
+
+    def __init__(
+        self,
+        dims,
+        in_channels: int = 3,
+        out_channels: int = 3,
+        blocks=[("res_x", 1)],
+        base_channels: int = 128,
+        layers_per_block: int = 2,
+        norm_num_groups: int = 32,
+        patch_size: int = 1,
+        norm_layer: str = "group_norm",
+        causal: bool = True,
+    ):
+        super().__init__()
+        self.patch_size = patch_size
+        self.layers_per_block = layers_per_block
+        out_channels = out_channels * patch_size**2
+        self.causal = causal
+        self.blocks_desc = blocks
+
+        # Compute output channel to be product of all channel-multiplier blocks
+        output_channel = base_channels
+        for block_name, block_params in list(reversed(blocks)):
+            block_params = block_params if isinstance(block_params, dict) else {}
+            if block_name == "res_x_y":
+                output_channel = output_channel * block_params.get("multiplier", 2)
+
+        self.conv_in = make_conv_nd(
+            dims,
+            in_channels,
+            output_channel,
+            kernel_size=3,
+            stride=1,
+            padding=1,
+            causal=True,
+        )
+
+        self.up_blocks = nn.ModuleList([])
+
+        for block_name, block_params in list(reversed(blocks)):
+            input_channel = output_channel
+            if isinstance(block_params, int):
+                block_params = {"num_layers": block_params}
+
+            if block_name == "res_x":
+                block = UNetMidBlock3D(
+                    dims=dims,
+                    in_channels=input_channel,
+                    num_layers=block_params["num_layers"],
+                    resnet_eps=1e-6,
+                    resnet_groups=norm_num_groups,
+                    norm_layer=norm_layer,
+                )
+            elif block_name == "res_x_y":
+                output_channel = output_channel // block_params.get("multiplier", 2)
+                block = ResnetBlock3D(
+                    dims=dims,
+                    in_channels=input_channel,
+                    out_channels=output_channel,
+                    eps=1e-6,
+                    groups=norm_num_groups,
+                    norm_layer=norm_layer,
+                )
+            elif block_name == "compress_time":
+                block = DepthToSpaceUpsample(
+                    dims=dims, in_channels=input_channel, stride=(2, 1, 1)
+                )
+            elif block_name == "compress_space":
+                block = DepthToSpaceUpsample(
+                    dims=dims, in_channels=input_channel, stride=(1, 2, 2)
+                )
+            elif block_name == "compress_all":
+                block = DepthToSpaceUpsample(
+                    dims=dims,
+                    in_channels=input_channel,
+                    stride=(2, 2, 2),
+                    residual=block_params.get("residual", False),
+                )
+            else:
+                raise ValueError(f"unknown layer: {block_name}")
+
+            self.up_blocks.append(block)
+
+        if norm_layer == "group_norm":
+            self.conv_norm_out = nn.GroupNorm(
+                num_channels=output_channel, num_groups=norm_num_groups, eps=1e-6
+            )
+        elif norm_layer == "pixel_norm":
+            self.conv_norm_out = PixelNorm()
+        elif norm_layer == "layer_norm":
+            self.conv_norm_out = LayerNorm(output_channel, eps=1e-6)
+
+        self.conv_act = nn.SiLU()
+        self.conv_out = make_conv_nd(
+            dims, output_channel, out_channels, 3, padding=1, causal=True
+        )
+
+        self.gradient_checkpointing = False
+
+    # def forward(self, sample: torch.FloatTensor, target_shape) -> torch.FloatTensor:
+    def forward(self, sample: torch.FloatTensor) -> torch.FloatTensor:
+        r"""The forward method of the `Decoder` class."""
+        # assert target_shape is not None, "target_shape must be provided"
+
+        sample = self.conv_in(sample, causal=self.causal)
+
+        upscale_dtype = next(iter(self.up_blocks.parameters())).dtype
+
+        checkpoint_fn = (
+            partial(torch.utils.checkpoint.checkpoint, use_reentrant=False)
+            if self.gradient_checkpointing and self.training
+            else lambda x: x
+        )
+
+        sample = sample.to(upscale_dtype)
+
+        for up_block in self.up_blocks:
+            sample = checkpoint_fn(up_block)(sample, causal=self.causal)
+
+        sample = self.conv_norm_out(sample)
+        sample = self.conv_act(sample)
+        sample = self.conv_out(sample, causal=self.causal)
+
+        sample = unpatchify(sample, patch_size_hw=self.patch_size, patch_size_t=1)
+
+        return sample
+
+
+class UNetMidBlock3D(nn.Module):
+    """
+    A 3D UNet mid-block [`UNetMidBlock3D`] with multiple residual blocks.
+
+    Args:
+        in_channels (`int`): The number of input channels.
+        dropout (`float`, *optional*, defaults to 0.0): The dropout rate.
+        num_layers (`int`, *optional*, defaults to 1): The number of residual blocks.
+        resnet_eps (`float`, *optional*, 1e-6 ): The epsilon value for the resnet blocks.
+        resnet_groups (`int`, *optional*, defaults to 32):
+            The number of groups to use in the group normalization layers of the resnet blocks.
+
+    Returns:
+        `torch.FloatTensor`: The output of the last residual block, which is a tensor of shape `(batch_size,
+        in_channels, height, width)`.
+
+    """
+
+    def __init__(
+        self,
+        dims: Union[int, Tuple[int, int]],
+        in_channels: int,
+        dropout: float = 0.0,
+        num_layers: int = 1,
+        resnet_eps: float = 1e-6,
+        resnet_groups: int = 32,
+        norm_layer: str = "group_norm",
+    ):
+        super().__init__()
+        resnet_groups = (
+            resnet_groups if resnet_groups is not None else min(in_channels // 4, 32)
+        )
+
+        self.res_blocks = nn.ModuleList(
+            [
+                ResnetBlock3D(
+                    dims=dims,
+                    in_channels=in_channels,
+                    out_channels=in_channels,
+                    eps=resnet_eps,
+                    groups=resnet_groups,
+                    dropout=dropout,
+                    norm_layer=norm_layer,
+                )
+                for _ in range(num_layers)
+            ]
+        )
+
+    def forward(
+        self, hidden_states: torch.FloatTensor, causal: bool = True
+    ) -> torch.FloatTensor:
+        for resnet in self.res_blocks:
+            hidden_states = resnet(hidden_states, causal=causal)
+
+        return hidden_states
+
+
+class DepthToSpaceUpsample(nn.Module):
+    def __init__(self, dims, in_channels, stride, residual=False):
+        super().__init__()
+        self.stride = stride
+        self.out_channels = math.prod(stride) * in_channels
+        self.conv = make_conv_nd(
+            dims=dims,
+            in_channels=in_channels,
+            out_channels=self.out_channels,
+            kernel_size=3,
+            stride=1,
+            causal=True,
+        )
+        self.residual = residual
+
+    def forward(self, x, causal: bool = True):
+        if self.residual:
+            # Reshape and duplicate the input to match the output shape
+            x_in = rearrange(
+                x,
+                "b (c p1 p2 p3) d h w -> b c (d p1) (h p2) (w p3)",
+                p1=self.stride[0],
+                p2=self.stride[1],
+                p3=self.stride[2],
+            )
+            x_in = x_in.repeat(1, math.prod(self.stride), 1, 1, 1)
+            if self.stride[0] == 2:
+                x_in = x_in[:, :, 1:, :, :]
+        x = self.conv(x, causal=causal)
+        x = rearrange(
+            x,
+            "b (c p1 p2 p3) d h w -> b c (d p1) (h p2) (w p3)",
+            p1=self.stride[0],
+            p2=self.stride[1],
+            p3=self.stride[2],
+        )
+        if self.stride[0] == 2:
+            x = x[:, :, 1:, :, :]
+        if self.residual:
+            x = x + x_in
+        return x
+
+
+class LayerNorm(nn.Module):
+    def __init__(self, dim, eps, elementwise_affine=True) -> None:
+        super().__init__()
+        self.norm = nn.LayerNorm(dim, eps=eps, elementwise_affine=elementwise_affine)
+
+    def forward(self, x):
+        x = rearrange(x, "b c d h w -> b d h w c")
+        x = self.norm(x)
+        x = rearrange(x, "b d h w c -> b c d h w")
+        return x
+
+
+class ResnetBlock3D(nn.Module):
+    r"""
+    A Resnet block.
+
+    Parameters:
+        in_channels (`int`): The number of channels in the input.
+        out_channels (`int`, *optional*, default to be `None`):
+            The number of output channels for the first conv layer. If None, same as `in_channels`.
+        dropout (`float`, *optional*, defaults to `0.0`): The dropout probability to use.
+        groups (`int`, *optional*, default to `32`): The number of groups to use for the first normalization layer.
+        eps (`float`, *optional*, defaults to `1e-6`): The epsilon to use for the normalization.
+    """
+
+    def __init__(
+        self,
+        dims: Union[int, Tuple[int, int]],
+        in_channels: int,
+        out_channels: Optional[int] = None,
+        dropout: float = 0.0,
+        groups: int = 32,
+        eps: float = 1e-6,
+        norm_layer: str = "group_norm",
+    ):
+        super().__init__()
+        self.in_channels = in_channels
+        out_channels = in_channels if out_channels is None else out_channels
+        self.out_channels = out_channels
+
+        if norm_layer == "group_norm":
+            self.norm1 = nn.GroupNorm(
+                num_groups=groups, num_channels=in_channels, eps=eps, affine=True
+            )
+        elif norm_layer == "pixel_norm":
+            self.norm1 = PixelNorm()
+        elif norm_layer == "layer_norm":
+            self.norm1 = LayerNorm(in_channels, eps=eps, elementwise_affine=True)
+
+        self.non_linearity = nn.SiLU()
+
+        self.conv1 = make_conv_nd(
+            dims,
+            in_channels,
+            out_channels,
+            kernel_size=3,
+            stride=1,
+            padding=1,
+            causal=True,
+        )
+
+        if norm_layer == "group_norm":
+            self.norm2 = nn.GroupNorm(
+                num_groups=groups, num_channels=out_channels, eps=eps, affine=True
+            )
+        elif norm_layer == "pixel_norm":
+            self.norm2 = PixelNorm()
+        elif norm_layer == "layer_norm":
+            self.norm2 = LayerNorm(out_channels, eps=eps, elementwise_affine=True)
+
+        self.dropout = torch.nn.Dropout(dropout)
+
+        self.conv2 = make_conv_nd(
+            dims,
+            out_channels,
+            out_channels,
+            kernel_size=3,
+            stride=1,
+            padding=1,
+            causal=True,
+        )
+
+        self.conv_shortcut = (
+            make_linear_nd(
+                dims=dims, in_channels=in_channels, out_channels=out_channels
+            )
+            if in_channels != out_channels
+            else nn.Identity()
+        )
+
+        self.norm3 = (
+            LayerNorm(in_channels, eps=eps, elementwise_affine=True)
+            if in_channels != out_channels
+            else nn.Identity()
+        )
+
+    def forward(
+        self,
+        input_tensor: torch.FloatTensor,
+        causal: bool = True,
+    ) -> torch.FloatTensor:
+        hidden_states = input_tensor
+
+        hidden_states = self.norm1(hidden_states)
+
+        hidden_states = self.non_linearity(hidden_states)
+
+        hidden_states = self.conv1(hidden_states, causal=causal)
+
+        hidden_states = self.norm2(hidden_states)
+
+        hidden_states = self.non_linearity(hidden_states)
+
+        hidden_states = self.dropout(hidden_states)
+
+        hidden_states = self.conv2(hidden_states, causal=causal)
+
+        input_tensor = self.norm3(input_tensor)
+
+        input_tensor = self.conv_shortcut(input_tensor)
+
+        output_tensor = input_tensor + hidden_states
+
+        return output_tensor
+
+
+def patchify(x, patch_size_hw, patch_size_t=1):
+    if patch_size_hw == 1 and patch_size_t == 1:
+        return x
+    if x.dim() == 4:
+        x = rearrange(
+            x, "b c (h q) (w r) -> b (c r q) h w", q=patch_size_hw, r=patch_size_hw
+        )
+    elif x.dim() == 5:
+        x = rearrange(
+            x,
+            "b c (f p) (h q) (w r) -> b (c p r q) f h w",
+            p=patch_size_t,
+            q=patch_size_hw,
+            r=patch_size_hw,
+        )
+    else:
+        raise ValueError(f"Invalid input shape: {x.shape}")
+
+    return x
+
+
+def unpatchify(x, patch_size_hw, patch_size_t=1):
+    if patch_size_hw == 1 and patch_size_t == 1:
+        return x
+
+    if x.dim() == 4:
+        x = rearrange(
+            x, "b (c r q) h w -> b c (h q) (w r)", q=patch_size_hw, r=patch_size_hw
+        )
+    elif x.dim() == 5:
+        x = rearrange(
+            x,
+            "b (c p r q) f h w -> b c (f p) (h q) (w r)",
+            p=patch_size_t,
+            q=patch_size_hw,
+            r=patch_size_hw,
+        )
+
+    return x
+
+class processor(nn.Module):
+    def __init__(self):
+        super().__init__()
+        self.register_buffer("std-of-means", torch.empty(128))
+        self.register_buffer("mean-of-means", torch.empty(128))
+        self.register_buffer("mean-of-stds", torch.empty(128))
+        self.register_buffer("mean-of-stds_over_std-of-means", torch.empty(128))
+        self.register_buffer("channel", torch.empty(128))
+
+    def un_normalize(self, x):
+        return (x * self.get_buffer("std-of-means").view(1, -1, 1, 1, 1)) + self.get_buffer("mean-of-means").view(1, -1, 1, 1, 1)
+
+    def normalize(self, x):
+        return (x - self.get_buffer("mean-of-means").view(1, -1, 1, 1, 1)) / self.get_buffer("std-of-means").view(1, -1, 1, 1, 1)
+
+class VideoVAE(nn.Module):
+    def __init__(self):
+        super().__init__()
+        config = {
+            "_class_name": "CausalVideoAutoencoder",
+            "dims": 3,
+            "in_channels": 3,
+            "out_channels": 3,
+            "latent_channels": 128,
+            "blocks": [
+                ["res_x", 4],
+                ["compress_all", 1],
+                ["res_x_y", 1],
+                ["res_x", 3],
+                ["compress_all", 1],
+                ["res_x_y", 1],
+                ["res_x", 3],
+                ["compress_all", 1],
+                ["res_x", 3],
+                ["res_x", 4],
+            ],
+            "scaling_factor": 1.0,
+            "norm_layer": "pixel_norm",
+            "patch_size": 4,
+            "latent_log_var": "uniform",
+            "use_quant_conv": False,
+            "causal_decoder": False,
+        }
+
+        double_z = config.get("double_z", True)
+        latent_log_var = config.get(
+            "latent_log_var", "per_channel" if double_z else "none"
+        )
+
+        self.encoder = Encoder(
+            dims=config["dims"],
+            in_channels=config.get("in_channels", 3),
+            out_channels=config["latent_channels"],
+            blocks=config.get("encoder_blocks", config.get("blocks")),
+            patch_size=config.get("patch_size", 1),
+            latent_log_var=latent_log_var,
+            norm_layer=config.get("norm_layer", "group_norm"),
+        )
+
+        self.decoder = Decoder(
+            dims=config["dims"],
+            in_channels=config["latent_channels"],
+            out_channels=config.get("out_channels", 3),
+            blocks=config.get("decoder_blocks", config.get("blocks")),
+            patch_size=config.get("patch_size", 1),
+            norm_layer=config.get("norm_layer", "group_norm"),
+            causal=config.get("causal_decoder", False),
+        )
+
+        self.per_channel_statistics = processor()
+
+    def encode(self, x):
+        means, logvar = torch.chunk(self.encoder(x), 2, dim=1)
+        return self.per_channel_statistics.normalize(means)
+
+    def decode(self, x):
+        return self.decoder(self.per_channel_statistics.un_normalize(x))
+