hunyuan_video.md

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<div style="float: right;">
  <div class="flex flex-wrap space-x-1">
    <a href="https://huggingface.co/docs/diffusers/main/en/tutorials/using_peft_for_inference" target="_blank" rel="noopener">
      <img alt="LoRA" src="https://img.shields.io/badge/LoRA-d8b4fe?style=flat"/>
    </a>
  </div>
</div>

# HunyuanVideo

[HunyuanVideo](https://huggingface.co/papers/2412.03603) is a 13B parameter diffusion transformer model designed to be competitive with closed-source video foundation models and enable wider community access. This model uses a "dual-stream to single-stream" architecture to separately process the video and text tokens first, before concatenating and feeding them to the transformer to fuse the multimodal information. A pretrained multimodal large language model (MLLM) is used as the encoder because it has better image-text alignment, better image detail description and reasoning, and it can be used as a zero-shot learner if system instructions are added to user prompts. Finally, HunyuanVideo uses a 3D causal variational autoencoder to more efficiently process video data at the original resolution and frame rate.

You can find all the original HunyuanVideo checkpoints under the [Tencent](https://huggingface.co/tencent) organization.

> [!TIP]
> Click on the HunyuanVideo models in the right sidebar for more examples of video generation tasks.
>
> The examples below use a checkpoint from [hunyuanvideo-community](https://huggingface.co/hunyuanvideo-community) because the weights are stored in a layout compatible with Diffusers.

The example below demonstrates how to generate a video optimized for memory or inference speed.

<hfoptions id="usage">
<hfoption id="memory">

Refer to the [Reduce memory usage](../../optimization/memory) guide for more details about the various memory saving techniques.

The quantized HunyuanVideo model below requires ~14GB of VRAM.

```py
import torch
from diffusers import AutoModel, HunyuanVideoPipeline
from diffusers.quantizers import PipelineQuantizationConfig
from diffusers.utils import export_to_video

# quantize weights to int4 with bitsandbytes
pipeline_quant_config = PipelineQuantizationConfig(
    quant_backend="bitsandbytes_4bit",
    quant_kwargs={
      "load_in_4bit": True,
      "bnb_4bit_quant_type": "nf4",
      "bnb_4bit_compute_dtype": torch.bfloat16
      },
    components_to_quantize="transformer"
)

pipeline = HunyuanVideoPipeline.from_pretrained(
    "hunyuanvideo-community/HunyuanVideo",
    quantization_config=pipeline_quant_config,
    torch_dtype=torch.bfloat16,
)

# model-offloading and tiling
pipeline.enable_model_cpu_offload()
pipeline.vae.enable_tiling()

prompt = "A fluffy teddy bear sits on a bed of soft pillows surrounded by children's toys."
video = pipeline(prompt=prompt, num_frames=61, num_inference_steps=30).frames[0]
export_to_video(video, "output.mp4", fps=15)
```

</hfoption>
<hfoption id="inference speed">

[Compilation](../../optimization/fp16#torchcompile) is slow the first time but subsequent calls to the pipeline are faster.

```py
import torch
from diffusers import AutoModel, HunyuanVideoPipeline
from diffusers.quantizers import PipelineQuantizationConfig
from diffusers.utils import export_to_video

# quantize weights to int4 with bitsandbytes
pipeline_quant_config = PipelineQuantizationConfig(
    quant_backend="bitsandbytes_4bit",
    quant_kwargs={
      "load_in_4bit": True,
      "bnb_4bit_quant_type": "nf4",
      "bnb_4bit_compute_dtype": torch.bfloat16
      },
    components_to_quantize="transformer"
)

pipeline = HunyuanVideoPipeline.from_pretrained(
    "hunyuanvideo-community/HunyuanVideo",
    quantization_config=pipeline_quant_config,
    torch_dtype=torch.bfloat16,
)

# model-offloading and tiling
pipeline.enable_model_cpu_offload()
pipeline.vae.enable_tiling()

# torch.compile
pipeline.transformer.to(memory_format=torch.channels_last)
pipeline.transformer = torch.compile(
    pipeline.transformer, mode="max-autotune", fullgraph=True
)

prompt = "A fluffy teddy bear sits on a bed of soft pillows surrounded by children's toys."
video = pipeline(prompt=prompt, num_frames=61, num_inference_steps=30).frames[0]
export_to_video(video, "output.mp4", fps=15)
```

</hfoption>
</hfoptions>

## Notes

- HunyuanVideo supports LoRAs with [`~loaders.HunyuanVideoLoraLoaderMixin.load_lora_weights`].

  <details>
  <summary>Show example code</summary>

  ```py
  import torch
  from diffusers import AutoModel, HunyuanVideoPipeline
  from diffusers.quantizers import PipelineQuantizationConfig
  from diffusers.utils import export_to_video

  # quantize weights to int4 with bitsandbytes
  pipeline_quant_config = PipelineQuantizationConfig(
      quant_backend="bitsandbytes_4bit",
      quant_kwargs={
        "load_in_4bit": True,
        "bnb_4bit_quant_type": "nf4",
        "bnb_4bit_compute_dtype": torch.bfloat16
        },
      components_to_quantize="transformer"
  )

  pipeline = HunyuanVideoPipeline.from_pretrained(
      "hunyuanvideo-community/HunyuanVideo",
      quantization_config=pipeline_quant_config,
      torch_dtype=torch.bfloat16,
  )

  # load LoRA weights
  pipeline.load_lora_weights("https://huggingface.co/lucataco/hunyuan-steamboat-willie-10", adapter_name="steamboat-willie")
  pipeline.set_adapters("steamboat-willie", 0.9)

  # model-offloading and tiling
  pipeline.enable_model_cpu_offload()
  pipeline.vae.enable_tiling()

  # use "In the style of SWR" to trigger the LoRA
  prompt = """
  In the style of SWR. A black and white animated scene featuring a fluffy teddy bear sits on a bed of soft pillows surrounded by children's toys.
  """
  video = pipeline(prompt=prompt, num_frames=61, num_inference_steps=30).frames[0]
  export_to_video(video, "output.mp4", fps=15)
  ```

  </details>

- Refer to the table below for recommended inference values.

  | parameter | recommended value |
  |---|---|
  | text encoder dtype | `torch.float16` |
  | transformer dtype | `torch.bfloat16` |
  | vae dtype | `torch.float16` |
  | `num_frames (k)` | 4 * `k` + 1 |

- Try lower `shift` values (`2.0` to `5.0`) for lower resolution videos and higher `shift` values (`7.0` to `12.0`) for higher resolution images.

## HunyuanVideoPipeline

[[autodoc]] HunyuanVideoPipeline
  - all
  - __call__

## HunyuanVideoPipelineOutput

[[autodoc]] pipelines.hunyuan_video.pipeline_output.HunyuanVideoPipelineOutput