LTX 0.9.5 (#10968)

* update


---------

Co-authored-by: YiYi Xu <yixu310@gmail.com>
Co-authored-by: hlky <hlky@hlky.ac>

docs/source/en/api/pipelines/ltx_video.md

@@ -196,6 +196,12 @@ export_to_video(video, "ship.mp4", fps=24)
   - all
   - __call__
 
+## LTXConditionPipeline
+
+[[autodoc]] LTXConditionPipeline
+  - all
+  - __call__
+
 ## LTXPipelineOutput
 
 [[autodoc]] pipelines.ltx.pipeline_output.LTXPipelineOutput

scripts/convert_ltx_to_diffusers.py

@@ -74,6 +74,32 @@ VAE_091_RENAME_DICT = {
     "last_scale_shift_table": "scale_shift_table",
 }
 
+VAE_095_RENAME_DICT = {
+    # decoder
+    "up_blocks.0": "mid_block",
+    "up_blocks.1": "up_blocks.0.upsamplers.0",
+    "up_blocks.2": "up_blocks.0",
+    "up_blocks.3": "up_blocks.1.upsamplers.0",
+    "up_blocks.4": "up_blocks.1",
+    "up_blocks.5": "up_blocks.2.upsamplers.0",
+    "up_blocks.6": "up_blocks.2",
+    "up_blocks.7": "up_blocks.3.upsamplers.0",
+    "up_blocks.8": "up_blocks.3",
+    # encoder
+    "down_blocks.0": "down_blocks.0",
+    "down_blocks.1": "down_blocks.0.downsamplers.0",
+    "down_blocks.2": "down_blocks.1",
+    "down_blocks.3": "down_blocks.1.downsamplers.0",
+    "down_blocks.4": "down_blocks.2",
+    "down_blocks.5": "down_blocks.2.downsamplers.0",
+    "down_blocks.6": "down_blocks.3",
+    "down_blocks.7": "down_blocks.3.downsamplers.0",
+    "down_blocks.8": "mid_block",
+    # common
+    "last_time_embedder": "time_embedder",
+    "last_scale_shift_table": "scale_shift_table",
+}
+
 VAE_SPECIAL_KEYS_REMAP = {
     "per_channel_statistics.channel": remove_keys_,
     "per_channel_statistics.mean-of-means": remove_keys_,
@@ -81,10 +107,6 @@ VAE_SPECIAL_KEYS_REMAP = {
     "model.diffusion_model": remove_keys_,
 }
 
-VAE_091_SPECIAL_KEYS_REMAP = {
-    "timestep_scale_multiplier": remove_keys_,
-}
-
 
 def get_state_dict(saved_dict: Dict[str, Any]) -> Dict[str, Any]:
     state_dict = saved_dict
@@ -104,12 +126,16 @@ def update_state_dict_inplace(state_dict: Dict[str, Any], old_key: str, new_key:
 def convert_transformer(
     ckpt_path: str,
     dtype: torch.dtype,
+    version: str = "0.9.0",
 ):
     PREFIX_KEY = "model.diffusion_model."
 
     original_state_dict = get_state_dict(load_file(ckpt_path))
+    config = {}
+    if version == "0.9.5":
+        config["_use_causal_rope_fix"] = True
     with init_empty_weights():
-        transformer = LTXVideoTransformer3DModel()
+        transformer = LTXVideoTransformer3DModel(**config)
 
     for key in list(original_state_dict.keys()):
         new_key = key[:]
@@ -161,12 +187,19 @@ def get_vae_config(version: str) -> Dict[str, Any]:
             "out_channels": 3,
             "latent_channels": 128,
             "block_out_channels": (128, 256, 512, 512),
+            "down_block_types": (
+                "LTXVideoDownBlock3D",
+                "LTXVideoDownBlock3D",
+                "LTXVideoDownBlock3D",
+                "LTXVideoDownBlock3D",
+            ),
             "decoder_block_out_channels": (128, 256, 512, 512),
             "layers_per_block": (4, 3, 3, 3, 4),
             "decoder_layers_per_block": (4, 3, 3, 3, 4),
             "spatio_temporal_scaling": (True, True, True, False),
             "decoder_spatio_temporal_scaling": (True, True, True, False),
             "decoder_inject_noise": (False, False, False, False, False),
+            "downsample_type": ("conv", "conv", "conv", "conv"),
             "upsample_residual": (False, False, False, False),
             "upsample_factor": (1, 1, 1, 1),
             "patch_size": 4,
@@ -183,12 +216,19 @@ def get_vae_config(version: str) -> Dict[str, Any]:
             "out_channels": 3,
             "latent_channels": 128,
             "block_out_channels": (128, 256, 512, 512),
+            "down_block_types": (
+                "LTXVideoDownBlock3D",
+                "LTXVideoDownBlock3D",
+                "LTXVideoDownBlock3D",
+                "LTXVideoDownBlock3D",
+            ),
             "decoder_block_out_channels": (256, 512, 1024),
             "layers_per_block": (4, 3, 3, 3, 4),
             "decoder_layers_per_block": (5, 6, 7, 8),
             "spatio_temporal_scaling": (True, True, True, False),
             "decoder_spatio_temporal_scaling": (True, True, True),
             "decoder_inject_noise": (True, True, True, False),
+            "downsample_type": ("conv", "conv", "conv", "conv"),
             "upsample_residual": (True, True, True),
             "upsample_factor": (2, 2, 2),
             "timestep_conditioning": True,
@@ -200,7 +240,38 @@ def get_vae_config(version: str) -> Dict[str, Any]:
             "decoder_causal": False,
         }
         VAE_KEYS_RENAME_DICT.update(VAE_091_RENAME_DICT)
-        VAE_SPECIAL_KEYS_REMAP.update(VAE_091_SPECIAL_KEYS_REMAP)
+    elif version == "0.9.5":
+        config = {
+            "in_channels": 3,
+            "out_channels": 3,
+            "latent_channels": 128,
+            "block_out_channels": (128, 256, 512, 1024, 2048),
+            "down_block_types": (
+                "LTXVideo095DownBlock3D",
+                "LTXVideo095DownBlock3D",
+                "LTXVideo095DownBlock3D",
+                "LTXVideo095DownBlock3D",
+            ),
+            "decoder_block_out_channels": (256, 512, 1024),
+            "layers_per_block": (4, 6, 6, 2, 2),
+            "decoder_layers_per_block": (5, 5, 5, 5),
+            "spatio_temporal_scaling": (True, True, True, True),
+            "decoder_spatio_temporal_scaling": (True, True, True),
+            "decoder_inject_noise": (False, False, False, False),
+            "downsample_type": ("spatial", "temporal", "spatiotemporal", "spatiotemporal"),
+            "upsample_residual": (True, True, True),
+            "upsample_factor": (2, 2, 2),
+            "timestep_conditioning": True,
+            "patch_size": 4,
+            "patch_size_t": 1,
+            "resnet_norm_eps": 1e-6,
+            "scaling_factor": 1.0,
+            "encoder_causal": True,
+            "decoder_causal": False,
+            "spatial_compression_ratio": 32,
+            "temporal_compression_ratio": 8,
+        }
+        VAE_KEYS_RENAME_DICT.update(VAE_095_RENAME_DICT)
     return config
 
 
@@ -223,7 +294,7 @@ def get_args():
     parser.add_argument("--output_path", type=str, required=True, help="Path where converted model should be saved")
     parser.add_argument("--dtype", default="fp32", help="Torch dtype to save the model in.")
     parser.add_argument(
-        "--version", type=str, default="0.9.0", choices=["0.9.0", "0.9.1"], help="Version of the LTX model"
+        "--version", type=str, default="0.9.0", choices=["0.9.0", "0.9.1", "0.9.5"], help="Version of the LTX model"
     )
     return parser.parse_args()
 
@@ -277,14 +348,17 @@ if __name__ == "__main__":
         for param in text_encoder.parameters():
             param.data = param.data.contiguous()
 
-        scheduler = FlowMatchEulerDiscreteScheduler(
-            use_dynamic_shifting=True,
-            base_shift=0.95,
-            max_shift=2.05,
-            base_image_seq_len=1024,
-            max_image_seq_len=4096,
-            shift_terminal=0.1,
-        )
+        if args.version == "0.9.5":
+            scheduler = FlowMatchEulerDiscreteScheduler(use_dynamic_shifting=False)
+        else:
+            scheduler = FlowMatchEulerDiscreteScheduler(
+                use_dynamic_shifting=True,
+                base_shift=0.95,
+                max_shift=2.05,
+                base_image_seq_len=1024,
+                max_image_seq_len=4096,
+                shift_terminal=0.1,
+            )
 
         pipe = LTXPipeline(
             scheduler=scheduler,

src/diffusers/__init__.py

@@ -402,6 +402,7 @@ else:
             "LDMTextToImagePipeline",
             "LEditsPPPipelineStableDiffusion",
             "LEditsPPPipelineStableDiffusionXL",
+            "LTXConditionPipeline",
             "LTXImageToVideoPipeline",
             "LTXPipeline",
             "Lumina2Pipeline",
@@ -947,6 +948,7 @@ if TYPE_CHECKING or DIFFUSERS_SLOW_IMPORT:
             LDMTextToImagePipeline,
             LEditsPPPipelineStableDiffusion,
             LEditsPPPipelineStableDiffusionXL,
+            LTXConditionPipeline,
             LTXImageToVideoPipeline,
             LTXPipeline,
             Lumina2Pipeline,

src/diffusers/models/autoencoders/autoencoder_kl_ltx.py

@@ -196,6 +196,55 @@ class LTXVideoResnetBlock3d(nn.Module):
         return hidden_states
 
 
+class LTXVideoDownsampler3d(nn.Module):
+    def __init__(
+        self,
+        in_channels: int,
+        out_channels: int,
+        stride: Union[int, Tuple[int, int, int]] = 1,
+        is_causal: bool = True,
+        padding_mode: str = "zeros",
+    ) -> None:
+        super().__init__()
+
+        self.stride = stride if isinstance(stride, tuple) else (stride, stride, stride)
+        self.group_size = (in_channels * stride[0] * stride[1] * stride[2]) // out_channels
+
+        out_channels = out_channels // (self.stride[0] * self.stride[1] * self.stride[2])
+
+        self.conv = LTXVideoCausalConv3d(
+            in_channels=in_channels,
+            out_channels=out_channels,
+            kernel_size=3,
+            stride=1,
+            is_causal=is_causal,
+            padding_mode=padding_mode,
+        )
+
+    def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
+        hidden_states = torch.cat([hidden_states[:, :, : self.stride[0] - 1], hidden_states], dim=2)
+
+        residual = (
+            hidden_states.unflatten(4, (-1, self.stride[2]))
+            .unflatten(3, (-1, self.stride[1]))
+            .unflatten(2, (-1, self.stride[0]))
+        )
+        residual = residual.permute(0, 1, 3, 5, 7, 2, 4, 6).flatten(1, 4)
+        residual = residual.unflatten(1, (-1, self.group_size))
+        residual = residual.mean(dim=2)
+
+        hidden_states = self.conv(hidden_states)
+        hidden_states = (
+            hidden_states.unflatten(4, (-1, self.stride[2]))
+            .unflatten(3, (-1, self.stride[1]))
+            .unflatten(2, (-1, self.stride[0]))
+        )
+        hidden_states = hidden_states.permute(0, 1, 3, 5, 7, 2, 4, 6).flatten(1, 4)
+        hidden_states = hidden_states + residual
+
+        return hidden_states
+
+
 class LTXVideoUpsampler3d(nn.Module):
     def __init__(
         self,
@@ -204,6 +253,7 @@ class LTXVideoUpsampler3d(nn.Module):
         is_causal: bool = True,
         residual: bool = False,
         upscale_factor: int = 1,
+        padding_mode: str = "zeros",
     ) -> None:
         super().__init__()
 
@@ -219,6 +269,7 @@ class LTXVideoUpsampler3d(nn.Module):
             kernel_size=3,
             stride=1,
             is_causal=is_causal,
+            padding_mode=padding_mode,
         )
 
     def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
@@ -352,6 +403,118 @@ class LTXVideoDownBlock3D(nn.Module):
         return hidden_states
 
 
+class LTXVideo095DownBlock3D(nn.Module):
+    r"""
+    Down block used in the LTXVideo model.
+
+    Args:
+        in_channels (`int`):
+            Number of input channels.
+        out_channels (`int`, *optional*):
+            Number of output channels. If None, defaults to `in_channels`.
+        num_layers (`int`, defaults to `1`):
+            Number of resnet layers.
+        dropout (`float`, defaults to `0.0`):
+            Dropout rate.
+        resnet_eps (`float`, defaults to `1e-6`):
+            Epsilon value for normalization layers.
+        resnet_act_fn (`str`, defaults to `"swish"`):
+            Activation function to use.
+        spatio_temporal_scale (`bool`, defaults to `True`):
+            Whether or not to use a downsampling layer. If not used, output dimension would be same as input dimension.
+            Whether or not to downsample across temporal dimension.
+        is_causal (`bool`, defaults to `True`):
+            Whether this layer behaves causally (future frames depend only on past frames) or not.
+    """
+
+    _supports_gradient_checkpointing = True
+
+    def __init__(
+        self,
+        in_channels: int,
+        out_channels: Optional[int] = None,
+        num_layers: int = 1,
+        dropout: float = 0.0,
+        resnet_eps: float = 1e-6,
+        resnet_act_fn: str = "swish",
+        spatio_temporal_scale: bool = True,
+        is_causal: bool = True,
+        downsample_type: str = "conv",
+    ):
+        super().__init__()
+
+        out_channels = out_channels or in_channels
+
+        resnets = []
+        for _ in range(num_layers):
+            resnets.append(
+                LTXVideoResnetBlock3d(
+                    in_channels=in_channels,
+                    out_channels=in_channels,
+                    dropout=dropout,
+                    eps=resnet_eps,
+                    non_linearity=resnet_act_fn,
+                    is_causal=is_causal,
+                )
+            )
+        self.resnets = nn.ModuleList(resnets)
+
+        self.downsamplers = None
+        if spatio_temporal_scale:
+            self.downsamplers = nn.ModuleList()
+
+            if downsample_type == "conv":
+                self.downsamplers.append(
+                    LTXVideoCausalConv3d(
+                        in_channels=in_channels,
+                        out_channels=in_channels,
+                        kernel_size=3,
+                        stride=(2, 2, 2),
+                        is_causal=is_causal,
+                    )
+                )
+            elif downsample_type == "spatial":
+                self.downsamplers.append(
+                    LTXVideoDownsampler3d(
+                        in_channels=in_channels, out_channels=out_channels, stride=(1, 2, 2), is_causal=is_causal
+                    )
+                )
+            elif downsample_type == "temporal":
+                self.downsamplers.append(
+                    LTXVideoDownsampler3d(
+                        in_channels=in_channels, out_channels=out_channels, stride=(2, 1, 1), is_causal=is_causal
+                    )
+                )
+            elif downsample_type == "spatiotemporal":
+                self.downsamplers.append(
+                    LTXVideoDownsampler3d(
+                        in_channels=in_channels, out_channels=out_channels, stride=(2, 2, 2), is_causal=is_causal
+                    )
+                )
+
+        self.gradient_checkpointing = False
+
+    def forward(
+        self,
+        hidden_states: torch.Tensor,
+        temb: Optional[torch.Tensor] = None,
+        generator: Optional[torch.Generator] = None,
+    ) -> torch.Tensor:
+        r"""Forward method of the `LTXDownBlock3D` class."""
+
+        for i, resnet in enumerate(self.resnets):
+            if torch.is_grad_enabled() and self.gradient_checkpointing:
+                hidden_states = self._gradient_checkpointing_func(resnet, hidden_states, temb, generator)
+            else:
+                hidden_states = resnet(hidden_states, temb, generator)
+
+        if self.downsamplers is not None:
+            for downsampler in self.downsamplers:
+                hidden_states = downsampler(hidden_states)
+
+        return hidden_states
+
+
 # Adapted from diffusers.models.autoencoders.autoencoder_kl_cogvideox.CogVideoMidBlock3d
 class LTXVideoMidBlock3d(nn.Module):
     r"""
@@ -593,8 +756,15 @@ class LTXVideoEncoder3d(nn.Module):
         in_channels: int = 3,
         out_channels: int = 128,
         block_out_channels: Tuple[int, ...] = (128, 256, 512, 512),
+        down_block_types: Tuple[str, ...] = (
+            "LTXVideoDownBlock3D",
+            "LTXVideoDownBlock3D",
+            "LTXVideoDownBlock3D",
+            "LTXVideoDownBlock3D",
+        ),
         spatio_temporal_scaling: Tuple[bool, ...] = (True, True, True, False),
         layers_per_block: Tuple[int, ...] = (4, 3, 3, 3, 4),
+        downsample_type: Tuple[str, ...] = ("conv", "conv", "conv", "conv"),
         patch_size: int = 4,
         patch_size_t: int = 1,
         resnet_norm_eps: float = 1e-6,
@@ -617,20 +787,37 @@ class LTXVideoEncoder3d(nn.Module):
         )
 
         # down blocks
-        num_block_out_channels = len(block_out_channels)
+        is_ltx_095 = down_block_types[-1] == "LTXVideo095DownBlock3D"
+        num_block_out_channels = len(block_out_channels) - (1 if is_ltx_095 else 0)
         self.down_blocks = nn.ModuleList([])
         for i in range(num_block_out_channels):
             input_channel = output_channel
-            output_channel = block_out_channels[i + 1] if i + 1 < num_block_out_channels else block_out_channels[i]
+            if not is_ltx_095:
+                output_channel = block_out_channels[i + 1] if i + 1 < num_block_out_channels else block_out_channels[i]
+            else:
+                output_channel = block_out_channels[i + 1]
 
-            down_block = LTXVideoDownBlock3D(
-                in_channels=input_channel,
-                out_channels=output_channel,
-                num_layers=layers_per_block[i],
-                resnet_eps=resnet_norm_eps,
-                spatio_temporal_scale=spatio_temporal_scaling[i],
-                is_causal=is_causal,
-            )
+            if down_block_types[i] == "LTXVideoDownBlock3D":
+                down_block = LTXVideoDownBlock3D(
+                    in_channels=input_channel,
+                    out_channels=output_channel,
+                    num_layers=layers_per_block[i],
+                    resnet_eps=resnet_norm_eps,
+                    spatio_temporal_scale=spatio_temporal_scaling[i],
+                    is_causal=is_causal,
+                )
+            elif down_block_types[i] == "LTXVideo095DownBlock3D":
+                down_block = LTXVideo095DownBlock3D(
+                    in_channels=input_channel,
+                    out_channels=output_channel,
+                    num_layers=layers_per_block[i],
+                    resnet_eps=resnet_norm_eps,
+                    spatio_temporal_scale=spatio_temporal_scaling[i],
+                    is_causal=is_causal,
+                    downsample_type=downsample_type[i],
+                )
+            else:
+                raise ValueError(f"Unknown down block type: {down_block_types[i]}")
 
             self.down_blocks.append(down_block)
 
@@ -794,7 +981,9 @@ class LTXVideoDecoder3d(nn.Module):
         # timestep embedding
         self.time_embedder = None
         self.scale_shift_table = None
+        self.timestep_scale_multiplier = None
         if timestep_conditioning:
+            self.timestep_scale_multiplier = nn.Parameter(torch.tensor(1000.0, dtype=torch.float32))
             self.time_embedder = PixArtAlphaCombinedTimestepSizeEmbeddings(output_channel * 2, 0)
             self.scale_shift_table = nn.Parameter(torch.randn(2, output_channel) / output_channel**0.5)
 
@@ -803,6 +992,9 @@ class LTXVideoDecoder3d(nn.Module):
     def forward(self, hidden_states: torch.Tensor, temb: Optional[torch.Tensor] = None) -> torch.Tensor:
         hidden_states = self.conv_in(hidden_states)
 
+        if self.timestep_scale_multiplier is not None:
+            temb = temb * self.timestep_scale_multiplier
+
         if torch.is_grad_enabled() and self.gradient_checkpointing:
             hidden_states = self._gradient_checkpointing_func(self.mid_block, hidden_states, temb)
 
@@ -891,12 +1083,19 @@ class AutoencoderKLLTXVideo(ModelMixin, ConfigMixin, FromOriginalModelMixin):
         out_channels: int = 3,
         latent_channels: int = 128,
         block_out_channels: Tuple[int, ...] = (128, 256, 512, 512),
+        down_block_types: Tuple[str, ...] = (
+            "LTXVideoDownBlock3D",
+            "LTXVideoDownBlock3D",
+            "LTXVideoDownBlock3D",
+            "LTXVideoDownBlock3D",
+        ),
         decoder_block_out_channels: Tuple[int, ...] = (128, 256, 512, 512),
         layers_per_block: Tuple[int, ...] = (4, 3, 3, 3, 4),
         decoder_layers_per_block: Tuple[int, ...] = (4, 3, 3, 3, 4),
         spatio_temporal_scaling: Tuple[bool, ...] = (True, True, True, False),
         decoder_spatio_temporal_scaling: Tuple[bool, ...] = (True, True, True, False),
         decoder_inject_noise: Tuple[bool, ...] = (False, False, False, False, False),
+        downsample_type: Tuple[str, ...] = ("conv", "conv", "conv", "conv"),
         upsample_residual: Tuple[bool, ...] = (False, False, False, False),
         upsample_factor: Tuple[int, ...] = (1, 1, 1, 1),
         timestep_conditioning: bool = False,
@@ -906,6 +1105,8 @@ class AutoencoderKLLTXVideo(ModelMixin, ConfigMixin, FromOriginalModelMixin):
         scaling_factor: float = 1.0,
         encoder_causal: bool = True,
         decoder_causal: bool = False,
+        spatial_compression_ratio: int = None,
+        temporal_compression_ratio: int = None,
     ) -> None:
         super().__init__()
 
@@ -913,8 +1114,10 @@ class AutoencoderKLLTXVideo(ModelMixin, ConfigMixin, FromOriginalModelMixin):
             in_channels=in_channels,
             out_channels=latent_channels,
             block_out_channels=block_out_channels,
+            down_block_types=down_block_types,
             spatio_temporal_scaling=spatio_temporal_scaling,
             layers_per_block=layers_per_block,
+            downsample_type=downsample_type,
             patch_size=patch_size,
             patch_size_t=patch_size_t,
             resnet_norm_eps=resnet_norm_eps,
@@ -941,8 +1144,16 @@ class AutoencoderKLLTXVideo(ModelMixin, ConfigMixin, FromOriginalModelMixin):
         self.register_buffer("latents_mean", latents_mean, persistent=True)
         self.register_buffer("latents_std", latents_std, persistent=True)
 
-        self.spatial_compression_ratio = patch_size * 2 ** sum(spatio_temporal_scaling)
-        self.temporal_compression_ratio = patch_size_t * 2 ** sum(spatio_temporal_scaling)
+        self.spatial_compression_ratio = (
+            patch_size * 2 ** sum(spatio_temporal_scaling)
+            if spatial_compression_ratio is None
+            else spatial_compression_ratio
+        )
+        self.temporal_compression_ratio = (
+            patch_size_t * 2 ** sum(spatio_temporal_scaling)
+            if temporal_compression_ratio is None
+            else temporal_compression_ratio
+        )
 
         # When decoding a batch of video latents at a time, one can save memory by slicing across the batch dimension
         # to perform decoding of a single video latent at a time.

src/diffusers/models/transformers/transformer_ltx.py

@@ -14,7 +14,7 @@
 # limitations under the License.
 
 import math
-from typing import Any, Dict, Optional, Tuple
+from typing import Any, Dict, Optional, Tuple, Union
 
 import torch
 import torch.nn as nn
@@ -113,20 +113,19 @@ class LTXVideoRotaryPosEmbed(nn.Module):
         self.patch_size_t = patch_size_t
         self.theta = theta
 
-    def forward(
+    def _prepare_video_coords(
         self,
-        hidden_states: torch.Tensor,
+        batch_size: int,
         num_frames: int,
         height: int,
         width: int,
-        rope_interpolation_scale: Optional[Tuple[torch.Tensor, float, float]] = None,
-    ) -> Tuple[torch.Tensor, torch.Tensor]:
-        batch_size = hidden_states.size(0)
-
+        rope_interpolation_scale: Tuple[torch.Tensor, float, float],
+        device: torch.device,
+    ) -> torch.Tensor:
         # Always compute rope in fp32
-        grid_h = torch.arange(height, dtype=torch.float32, device=hidden_states.device)
-        grid_w = torch.arange(width, dtype=torch.float32, device=hidden_states.device)
-        grid_f = torch.arange(num_frames, dtype=torch.float32, device=hidden_states.device)
+        grid_h = torch.arange(height, dtype=torch.float32, device=device)
+        grid_w = torch.arange(width, dtype=torch.float32, device=device)
+        grid_f = torch.arange(num_frames, dtype=torch.float32, device=device)
         grid = torch.meshgrid(grid_f, grid_h, grid_w, indexing="ij")
         grid = torch.stack(grid, dim=0)
         grid = grid.unsqueeze(0).repeat(batch_size, 1, 1, 1, 1)
@@ -138,6 +137,38 @@ class LTXVideoRotaryPosEmbed(nn.Module):
 
         grid = grid.flatten(2, 4).transpose(1, 2)
 
+        return grid
+
+    def forward(
+        self,
+        hidden_states: torch.Tensor,
+        num_frames: Optional[int] = None,
+        height: Optional[int] = None,
+        width: Optional[int] = None,
+        rope_interpolation_scale: Optional[Tuple[torch.Tensor, float, float]] = None,
+        video_coords: Optional[torch.Tensor] = None,
+    ) -> Tuple[torch.Tensor, torch.Tensor]:
+        batch_size = hidden_states.size(0)
+
+        if video_coords is None:
+            grid = self._prepare_video_coords(
+                batch_size,
+                num_frames,
+                height,
+                width,
+                rope_interpolation_scale=rope_interpolation_scale,
+                device=hidden_states.device,
+            )
+        else:
+            grid = torch.stack(
+                [
+                    video_coords[:, 0] / self.base_num_frames,
+                    video_coords[:, 1] / self.base_height,
+                    video_coords[:, 2] / self.base_width,
+                ],
+                dim=-1,
+            )
+
         start = 1.0
         end = self.theta
         freqs = self.theta ** torch.linspace(
@@ -367,10 +398,11 @@ class LTXVideoTransformer3DModel(ModelMixin, ConfigMixin, FromOriginalModelMixin
         encoder_hidden_states: torch.Tensor,
         timestep: torch.LongTensor,
         encoder_attention_mask: torch.Tensor,
-        num_frames: int,
-        height: int,
-        width: int,
-        rope_interpolation_scale: Optional[Tuple[float, float, float]] = None,
+        num_frames: Optional[int] = None,
+        height: Optional[int] = None,
+        width: Optional[int] = None,
+        rope_interpolation_scale: Optional[Union[Tuple[float, float, float], torch.Tensor]] = None,
+        video_coords: Optional[torch.Tensor] = None,
         attention_kwargs: Optional[Dict[str, Any]] = None,
         return_dict: bool = True,
     ) -> torch.Tensor:
@@ -389,7 +421,7 @@ class LTXVideoTransformer3DModel(ModelMixin, ConfigMixin, FromOriginalModelMixin
                     "Passing `scale` via `attention_kwargs` when not using the PEFT backend is ineffective."
                 )
 
-        image_rotary_emb = self.rope(hidden_states, num_frames, height, width, rope_interpolation_scale)
+        image_rotary_emb = self.rope(hidden_states, num_frames, height, width, rope_interpolation_scale, video_coords)
 
         # convert encoder_attention_mask to a bias the same way we do for attention_mask
         if encoder_attention_mask is not None and encoder_attention_mask.ndim == 2:

src/diffusers/pipelines/__init__.py

@@ -264,7 +264,7 @@ else:
         ]
     )
     _import_structure["latte"] = ["LattePipeline"]
-    _import_structure["ltx"] = ["LTXPipeline", "LTXImageToVideoPipeline"]
+    _import_structure["ltx"] = ["LTXPipeline", "LTXImageToVideoPipeline", "LTXConditionPipeline"]
     _import_structure["lumina"] = ["LuminaPipeline", "LuminaText2ImgPipeline"]
     _import_structure["lumina2"] = ["Lumina2Pipeline", "Lumina2Text2ImgPipeline"]
     _import_structure["marigold"].extend(
@@ -618,7 +618,7 @@ if TYPE_CHECKING or DIFFUSERS_SLOW_IMPORT:
             LEditsPPPipelineStableDiffusion,
             LEditsPPPipelineStableDiffusionXL,
         )
-        from .ltx import LTXImageToVideoPipeline, LTXPipeline
+        from .ltx import LTXConditionPipeline, LTXImageToVideoPipeline, LTXPipeline
         from .lumina import LuminaPipeline, LuminaText2ImgPipeline
         from .lumina2 import Lumina2Pipeline, Lumina2Text2ImgPipeline
         from .marigold import (

src/diffusers/pipelines/ltx/__init__.py

@@ -23,6 +23,7 @@ except OptionalDependencyNotAvailable:
     _dummy_objects.update(get_objects_from_module(dummy_torch_and_transformers_objects))
 else:
     _import_structure["pipeline_ltx"] = ["LTXPipeline"]
+    _import_structure["pipeline_ltx_condition"] = ["LTXConditionPipeline"]
     _import_structure["pipeline_ltx_image2video"] = ["LTXImageToVideoPipeline"]
 
 if TYPE_CHECKING or DIFFUSERS_SLOW_IMPORT:
@@ -34,6 +35,7 @@ if TYPE_CHECKING or DIFFUSERS_SLOW_IMPORT:
         from ...utils.dummy_torch_and_transformers_objects import *
     else:
         from .pipeline_ltx import LTXPipeline
+        from .pipeline_ltx_condition import LTXConditionPipeline
         from .pipeline_ltx_image2video import LTXImageToVideoPipeline
 
 else:

src/diffusers/pipelines/ltx/pipeline_ltx.py

@@ -694,9 +694,8 @@ class LTXPipeline(DiffusionPipeline, FromSingleFileMixin, LTXVideoLoraLoaderMixi
         self._num_timesteps = len(timesteps)
 
         # 6. Prepare micro-conditions
-        latent_frame_rate = frame_rate / self.vae_temporal_compression_ratio
         rope_interpolation_scale = (
-            1 / latent_frame_rate,
+            self.vae_temporal_compression_ratio / frame_rate,
             self.vae_spatial_compression_ratio,
             self.vae_spatial_compression_ratio,
         )

src/diffusers/pipelines/ltx/pipeline_ltx_image2video.py

@@ -764,9 +764,8 @@ class LTXImageToVideoPipeline(DiffusionPipeline, FromSingleFileMixin, LTXVideoLo
         self._num_timesteps = len(timesteps)
 
         # 6. Prepare micro-conditions
-        latent_frame_rate = frame_rate / self.vae_temporal_compression_ratio
         rope_interpolation_scale = (
-            1 / latent_frame_rate,
+            self.vae_temporal_compression_ratio / frame_rate,
             self.vae_spatial_compression_ratio,
             self.vae_spatial_compression_ratio,
         )

src/diffusers/schedulers/scheduling_flow_match_euler_discrete.py

@@ -377,6 +377,7 @@ class FlowMatchEulerDiscreteScheduler(SchedulerMixin, ConfigMixin):
         s_tmax: float = float("inf"),
         s_noise: float = 1.0,
         generator: Optional[torch.Generator] = None,
+        per_token_timesteps: Optional[torch.Tensor] = None,
         return_dict: bool = True,
     ) -> Union[FlowMatchEulerDiscreteSchedulerOutput, Tuple]:
         """
@@ -397,6 +398,8 @@ class FlowMatchEulerDiscreteScheduler(SchedulerMixin, ConfigMixin):
                 Scaling factor for noise added to the sample.
             generator (`torch.Generator`, *optional*):
                 A random number generator.
+            per_token_timesteps (`torch.Tensor`, *optional*):
+                The timesteps for each token in the sample.
             return_dict (`bool`):
                 Whether or not to return a
                 [`~schedulers.scheduling_flow_match_euler_discrete.FlowMatchEulerDiscreteSchedulerOutput`] or tuple.
@@ -427,16 +430,26 @@ class FlowMatchEulerDiscreteScheduler(SchedulerMixin, ConfigMixin):
         # Upcast to avoid precision issues when computing prev_sample
         sample = sample.to(torch.float32)
 
-        sigma = self.sigmas[self.step_index]
-        sigma_next = self.sigmas[self.step_index + 1]
+        if per_token_timesteps is not None:
+            per_token_sigmas = per_token_timesteps / self.config.num_train_timesteps
 
-        prev_sample = sample + (sigma_next - sigma) * model_output
+            sigmas = self.sigmas[:, None, None]
+            lower_mask = sigmas < per_token_sigmas[None] - 1e-6
+            lower_sigmas = lower_mask * sigmas
+            lower_sigmas, _ = lower_sigmas.max(dim=0)
+            dt = (per_token_sigmas - lower_sigmas)[..., None]
+        else:
+            sigma = self.sigmas[self.step_index]
+            sigma_next = self.sigmas[self.step_index + 1]
+            dt = sigma_next - sigma
 
-        # Cast sample back to model compatible dtype
-        prev_sample = prev_sample.to(model_output.dtype)
+        prev_sample = sample + dt * model_output
 
         # upon completion increase step index by one
         self._step_index += 1
+        if per_token_timesteps is None:
+            # Cast sample back to model compatible dtype
+            prev_sample = prev_sample.to(model_output.dtype)
 
         if not return_dict:
             return (prev_sample,)

src/diffusers/utils/dummy_torch_and_transformers_objects.py

@@ -1217,6 +1217,21 @@ class LEditsPPPipelineStableDiffusionXL(metaclass=DummyObject):
         requires_backends(cls, ["torch", "transformers"])
 
 
+class LTXConditionPipeline(metaclass=DummyObject):
+    _backends = ["torch", "transformers"]
+
+    def __init__(self, *args, **kwargs):
+        requires_backends(self, ["torch", "transformers"])
+
+    @classmethod
+    def from_config(cls, *args, **kwargs):
+        requires_backends(cls, ["torch", "transformers"])
+
+    @classmethod
+    def from_pretrained(cls, *args, **kwargs):
+        requires_backends(cls, ["torch", "transformers"])
+
+
 class LTXImageToVideoPipeline(metaclass=DummyObject):
     _backends = ["torch", "transformers"]
 

tests/pipelines/ltx/test_ltx_condition.py

@@ -0,0 +1,284 @@
+# Copyright 2024 The HuggingFace Team.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import inspect
+import unittest
+
+import numpy as np
+import torch
+from transformers import AutoTokenizer, T5EncoderModel
+
+from diffusers import (
+    AutoencoderKLLTXVideo,
+    FlowMatchEulerDiscreteScheduler,
+    LTXConditionPipeline,
+    LTXVideoTransformer3DModel,
+)
+from diffusers.pipelines.ltx.pipeline_ltx_condition import LTXVideoCondition
+from diffusers.utils.testing_utils import enable_full_determinism, torch_device
+
+from ..pipeline_params import TEXT_TO_IMAGE_BATCH_PARAMS, TEXT_TO_IMAGE_IMAGE_PARAMS, TEXT_TO_IMAGE_PARAMS
+from ..test_pipelines_common import PipelineTesterMixin, to_np
+
+
+enable_full_determinism()
+
+
+class LTXConditionPipelineFastTests(PipelineTesterMixin, unittest.TestCase):
+    pipeline_class = LTXConditionPipeline
+    params = TEXT_TO_IMAGE_PARAMS - {"cross_attention_kwargs"}
+    batch_params = TEXT_TO_IMAGE_BATCH_PARAMS.union({"image"})
+    image_params = TEXT_TO_IMAGE_IMAGE_PARAMS
+    image_latents_params = TEXT_TO_IMAGE_IMAGE_PARAMS
+    required_optional_params = frozenset(
+        [
+            "num_inference_steps",
+            "generator",
+            "latents",
+            "return_dict",
+            "callback_on_step_end",
+            "callback_on_step_end_tensor_inputs",
+        ]
+    )
+    test_xformers_attention = False
+
+    def get_dummy_components(self):
+        torch.manual_seed(0)
+        transformer = LTXVideoTransformer3DModel(
+            in_channels=8,
+            out_channels=8,
+            patch_size=1,
+            patch_size_t=1,
+            num_attention_heads=4,
+            attention_head_dim=8,
+            cross_attention_dim=32,
+            num_layers=1,
+            caption_channels=32,
+        )
+
+        torch.manual_seed(0)
+        vae = AutoencoderKLLTXVideo(
+            in_channels=3,
+            out_channels=3,
+            latent_channels=8,
+            block_out_channels=(8, 8, 8, 8),
+            decoder_block_out_channels=(8, 8, 8, 8),
+            layers_per_block=(1, 1, 1, 1, 1),
+            decoder_layers_per_block=(1, 1, 1, 1, 1),
+            spatio_temporal_scaling=(True, True, False, False),
+            decoder_spatio_temporal_scaling=(True, True, False, False),
+            decoder_inject_noise=(False, False, False, False, False),
+            upsample_residual=(False, False, False, False),
+            upsample_factor=(1, 1, 1, 1),
+            timestep_conditioning=False,
+            patch_size=1,
+            patch_size_t=1,
+            encoder_causal=True,
+            decoder_causal=False,
+        )
+        vae.use_framewise_encoding = False
+        vae.use_framewise_decoding = False
+
+        torch.manual_seed(0)
+        scheduler = FlowMatchEulerDiscreteScheduler()
+        text_encoder = T5EncoderModel.from_pretrained("hf-internal-testing/tiny-random-t5")
+        tokenizer = AutoTokenizer.from_pretrained("hf-internal-testing/tiny-random-t5")
+
+        components = {
+            "transformer": transformer,
+            "vae": vae,
+            "scheduler": scheduler,
+            "text_encoder": text_encoder,
+            "tokenizer": tokenizer,
+        }
+        return components
+
+    def get_dummy_inputs(self, device, seed=0, use_conditions=False):
+        if str(device).startswith("mps"):
+            generator = torch.manual_seed(seed)
+        else:
+            generator = torch.Generator(device=device).manual_seed(seed)
+
+        image = torch.randn((1, 3, 32, 32), generator=generator, device=device)
+        if use_conditions:
+            conditions = LTXVideoCondition(
+                image=image,
+            )
+        else:
+            conditions = None
+
+        inputs = {
+            "conditions": conditions,
+            "image": None if use_conditions else image,
+            "prompt": "dance monkey",
+            "negative_prompt": "",
+            "generator": generator,
+            "num_inference_steps": 2,
+            "guidance_scale": 3.0,
+            "height": 32,
+            "width": 32,
+            # 8 * k + 1 is the recommendation
+            "num_frames": 9,
+            "max_sequence_length": 16,
+            "output_type": "pt",
+        }
+
+        return inputs
+
+    def test_inference(self):
+        device = "cpu"
+
+        components = self.get_dummy_components()
+        pipe = self.pipeline_class(**components)
+        pipe.to(device)
+        pipe.set_progress_bar_config(disable=None)
+
+        inputs = self.get_dummy_inputs(device)
+        inputs2 = self.get_dummy_inputs(device, use_conditions=True)
+        video = pipe(**inputs).frames
+        generated_video = video[0]
+        video2 = pipe(**inputs2).frames
+        generated_video2 = video2[0]
+
+        self.assertEqual(generated_video.shape, (9, 3, 32, 32))
+
+        max_diff = np.abs(generated_video - generated_video2).max()
+        self.assertLessEqual(max_diff, 1e-3)
+
+    def test_callback_inputs(self):
+        sig = inspect.signature(self.pipeline_class.__call__)
+        has_callback_tensor_inputs = "callback_on_step_end_tensor_inputs" in sig.parameters
+        has_callback_step_end = "callback_on_step_end" in sig.parameters
+
+        if not (has_callback_tensor_inputs and has_callback_step_end):
+            return
+
+        components = self.get_dummy_components()
+        pipe = self.pipeline_class(**components)
+        pipe = pipe.to(torch_device)
+        pipe.set_progress_bar_config(disable=None)
+        self.assertTrue(
+            hasattr(pipe, "_callback_tensor_inputs"),
+            f" {self.pipeline_class} should have `_callback_tensor_inputs` that defines a list of tensor variables its callback function can use as inputs",
+        )
+
+        def callback_inputs_subset(pipe, i, t, callback_kwargs):
+            # iterate over callback args
+            for tensor_name, tensor_value in callback_kwargs.items():
+                # check that we're only passing in allowed tensor inputs
+                assert tensor_name in pipe._callback_tensor_inputs
+
+            return callback_kwargs
+
+        def callback_inputs_all(pipe, i, t, callback_kwargs):
+            for tensor_name in pipe._callback_tensor_inputs:
+                assert tensor_name in callback_kwargs
+
+            # iterate over callback args
+            for tensor_name, tensor_value in callback_kwargs.items():
+                # check that we're only passing in allowed tensor inputs
+                assert tensor_name in pipe._callback_tensor_inputs
+
+            return callback_kwargs
+
+        inputs = self.get_dummy_inputs(torch_device)
+
+        # Test passing in a subset
+        inputs["callback_on_step_end"] = callback_inputs_subset
+        inputs["callback_on_step_end_tensor_inputs"] = ["latents"]
+        output = pipe(**inputs)[0]
+
+        # Test passing in a everything
+        inputs["callback_on_step_end"] = callback_inputs_all
+        inputs["callback_on_step_end_tensor_inputs"] = pipe._callback_tensor_inputs
+        output = pipe(**inputs)[0]
+
+        def callback_inputs_change_tensor(pipe, i, t, callback_kwargs):
+            is_last = i == (pipe.num_timesteps - 1)
+            if is_last:
+                callback_kwargs["latents"] = torch.zeros_like(callback_kwargs["latents"])
+            return callback_kwargs
+
+        inputs["callback_on_step_end"] = callback_inputs_change_tensor
+        inputs["callback_on_step_end_tensor_inputs"] = pipe._callback_tensor_inputs
+        output = pipe(**inputs)[0]
+        assert output.abs().sum() < 1e10
+
+    def test_inference_batch_single_identical(self):
+        self._test_inference_batch_single_identical(batch_size=3, expected_max_diff=1e-3)
+
+    def test_attention_slicing_forward_pass(
+        self, test_max_difference=True, test_mean_pixel_difference=True, expected_max_diff=1e-3
+    ):
+        if not self.test_attention_slicing:
+            return
+
+        components = self.get_dummy_components()
+        pipe = self.pipeline_class(**components)
+        for component in pipe.components.values():
+            if hasattr(component, "set_default_attn_processor"):
+                component.set_default_attn_processor()
+        pipe.to(torch_device)
+        pipe.set_progress_bar_config(disable=None)
+
+        generator_device = "cpu"
+        inputs = self.get_dummy_inputs(generator_device)
+        output_without_slicing = pipe(**inputs)[0]
+
+        pipe.enable_attention_slicing(slice_size=1)
+        inputs = self.get_dummy_inputs(generator_device)
+        output_with_slicing1 = pipe(**inputs)[0]
+
+        pipe.enable_attention_slicing(slice_size=2)
+        inputs = self.get_dummy_inputs(generator_device)
+        output_with_slicing2 = pipe(**inputs)[0]
+
+        if test_max_difference:
+            max_diff1 = np.abs(to_np(output_with_slicing1) - to_np(output_without_slicing)).max()
+            max_diff2 = np.abs(to_np(output_with_slicing2) - to_np(output_without_slicing)).max()
+            self.assertLess(
+                max(max_diff1, max_diff2),
+                expected_max_diff,
+                "Attention slicing should not affect the inference results",
+            )
+
+    def test_vae_tiling(self, expected_diff_max: float = 0.2):
+        generator_device = "cpu"
+        components = self.get_dummy_components()
+
+        pipe = self.pipeline_class(**components)
+        pipe.to("cpu")
+        pipe.set_progress_bar_config(disable=None)
+
+        # Without tiling
+        inputs = self.get_dummy_inputs(generator_device)
+        inputs["height"] = inputs["width"] = 128
+        output_without_tiling = pipe(**inputs)[0]
+
+        # With tiling
+        pipe.vae.enable_tiling(
+            tile_sample_min_height=96,
+            tile_sample_min_width=96,
+            tile_sample_stride_height=64,
+            tile_sample_stride_width=64,
+        )
+        inputs = self.get_dummy_inputs(generator_device)
+        inputs["height"] = inputs["width"] = 128
+        output_with_tiling = pipe(**inputs)[0]
+
+        self.assertLess(
+            (to_np(output_without_tiling) - to_np(output_with_tiling)).max(),
+            expected_diff_max,
+            "VAE tiling should not affect the inference results",
+        )