The bidirectional 3D Transformer used by AnyFlowPipeline. It is the
v0.35.1 Wan2.1 backbone with one structural change: the timestep embedder is replaced by
AnyFlowDualTimestepTextImageEmbedding, so every forward call conditions on both the source timestep
t and the target timestep r. This is the embedding required to learn the flow map
:math:\Phi_{r\leftarrow t} introduced in
AnyFlow (Yuchao Gu, Guian Fang et al., NUS ShowLab × NVIDIA).
For frame-level autoregressive (FAR causal) generation, use
AnyFlowFARTransformer3DModel instead.
from diffusers import AnyFlowTransformer3DModel
# Bidirectional AnyFlow checkpoint (T2V):
transformer = AnyFlowTransformer3DModel.from_pretrained(
"nvidia/AnyFlow-Wan2.1-T2V-1.3B-Diffusers", subfolder="transformer"
)[[autodoc]] AnyFlowTransformer3DModel