diffusers/pr_14333/en/api/models/ltx_video_transformer3d.md

LTXVideoTransformer3DModel

A Diffusion Transformer model for 3D data from LTX was introduced by Lightricks.

The model can be loaded with the following code snippet.

from diffusers import LTXVideoTransformer3DModel

transformer = LTXVideoTransformer3DModel.from_pretrained("Lightricks/LTX-Video", subfolder="transformer", dtype=torch.bfloat16).to("cuda")

LTXVideoTransformer3DModel[[diffusers.LTXVideoTransformer3DModel]]

diffusers.LTXVideoTransformer3DModel[[diffusers.LTXVideoTransformer3DModel]]

diffusers.LTXVideoTransformer3DModel(in_channels: int = 128, out_channels: int = 128, patch_size: int = 1, patch_size_t: int = 1, num_attention_heads: int = 32, attention_head_dim: int = 64, cross_attention_dim: int = 2048, num_layers: int = 28, activation_fn: str = 'gelu-approximate', qk_norm: str = 'rms_norm_across_heads', norm_elementwise_affine: bool = False, norm_eps: float = 1e-06, caption_channels: int = 4096, attention_bias: bool = True, attention_out_bias: bool = True)

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Parameters:

in_channels (int, defaults to 128) : The number of channels in the input.

out_channels (int, defaults to 128) : The number of channels in the output.

patch_size (int, defaults to 1) : The size of the spatial patches to use in the patch embedding layer.

patch_size_t (int, defaults to 1) : The size of the tmeporal patches to use in the patch embedding layer.

num_attention_heads (int, defaults to 32) : The number of heads to use for multi-head attention.

attention_head_dim (int, defaults to 64) : The number of channels in each head.

cross_attention_dim (int, defaults to 2048 ) : The number of channels for cross attention heads.

num_layers (int, defaults to 28) : The number of layers of Transformer blocks to use.

activation_fn (str, defaults to "gelu-approximate") : Activation function to use in feed-forward.

qk_norm (str, defaults to "rms_norm_across_heads") : The normalization layer to use.

A Transformer model for video-like data used in LTX.

forward[[diffusers.LTXVideoTransformer3DModel.forward]]

forward(hidden_states: Tensor, encoder_hidden_states: Tensor, timestep: LongTensor, encoder_attention_mask: Tensor, num_frames: int | None = None, height: int | None = None, width: int | None = None, rope_interpolation_scale: typing.Union[tuple[float, float, float], torch.Tensor, NoneType] = None, video_coords: typing.Optional[torch.Tensor] = None, attention_kwargs: dict[str, typing.Any] | None = None, return_dict: bool = True)

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Parameters:

hidden_states (torch.Tensor of shape (batch_size, sequence_length, in_channels)) : Input hidden_states.

encoder_hidden_states (torch.Tensor of shape (batch_size, sequence_len, embed_dims)) : Conditional embeddings (embeddings computed from the input conditions such as prompts) to use.

timestep (torch.LongTensor) : Used to indicate denoising step.

encoder_attention_mask (torch.Tensor) : Mask applied to encoder_hidden_states during attention.

num_frames (int, optional) : Number of frames in the video used to compute the rotary positional embeddings.

height (int, optional) : Height of the latent used to compute the rotary positional embeddings.

width (int, optional) : Width of the latent used to compute the rotary positional embeddings.

rope_interpolation_scale (tuple of float or torch.Tensor, optional) : Interpolation scale used by the rotary positional embeddings.

video_coords (torch.Tensor, optional) : Pre-computed video coordinates used by the rotary positional embeddings.

attention_kwargs (dict, optional) : A kwargs dictionary that if specified is passed along to the AttentionProcessor as defined under self.processor in diffusers.models.attention_processor.

return_dict (bool, optional, defaults to True) : Whether or not to return a ~models.transformer_2d.Transformer2DModelOutput instead of a plain tuple.

Returns: torch.Tensor

The denoised output tensor of shape (batch_size, sequence_length, out_channels).

The LTXVideoTransformer3DModel forward method.

Transformer2DModelOutput[[diffusers.models.modeling_outputs.Transformer2DModelOutput]]

diffusers.models.modeling_outputs.Transformer2DModelOutput[[diffusers.models.modeling_outputs.Transformer2DModelOutput]]

diffusers.models.modeling_outputs.Transformer2DModelOutput(sample: torch.Tensor)

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Parameters:

sample (torch.Tensor of shape (batch_size, num_channels, height, width) or (batch size, num_vector_embeds - 1, num_latent_pixels) if Transformer2DModel is discrete) : The hidden states output conditioned on the encoder_hidden_states input. If discrete, returns probability distributions for the unnoised latent pixels.

The output of Transformer2DModel.