FastVideo/FastH3-Omni-NVFP4-QAD-Comfy

FastH3 Omni NVFP4 QAD for ComfyUI

The ComfyUI-native NVFP4 QAD diffusion model for FastH3 Omni. It generates video with synchronized 32-kHz stereo audio from a prompt and ordered image, video and audio references in eight sampling steps.

Release collection · BF16 release · Shared ComfyUI components

Install

Place fasth3_omniref_qad_nvfp4_comfy.safetensors in:

ComfyUI/models/diffusion_models/fasth3_omniref_qad_nvfp4_comfy.safetensors

Download a compatible text encoder, video VAE and audio VAE from FastH3 Omni Comfy and place them in ComfyUI/models/text_encoders/ and ComfyUI/models/vae/. The audio VAE and the text encoder's reference-vision support are required. Select a text-encoder format supported by your GPU.

Accelerated NVFP4 inference requires NVIDIA Blackwell hardware. Use BF16 or FP8 on other GPU families. Quantized output can differ from BF16. This is the ComfyUI format; use the separate FastVideo-format model for FastVideo inference.

Generate video and audio

Use a current ComfyUI build with native MiniMax-H3 support and the MiniMax H3 Reference to Video conditioning node. Supply matching text-encoder, video-VAE and audio-VAE components.

• Eight sampling steps, guidance 1.0.
• Video shift 12.0 and audio shift 3.0.
• Reference inputs use <Picture 1>, <Video 1> and <Audio 1> tags in the prompt.
• The audio VAE is required for synchronized audio output.

ComfyUI uses its own model layout, sampler and runtime kernels; outputs can differ from FastVideo and UniServe.

Other runtimes

• UniServe — GB200/B200, RTX PRO 6000 Blackwell and Hopper: use the BF16 release and deployment guide.
• FastVideo local AI — DGX Spark and RTX 5090: use the FastVideo-format NVFP4 QAD model and local inference guide.

Local AI resources

Run FastH3 Omni on DGX Spark or RTX 5090 through FastVideo using the FastVideo-format NVFP4 QAD weights. Start with the FastVideo cookbook and FastH3 Omni recipe builder; use the Spark recipe or RTX 5090 recipe and the local inference guide for the AdaLN table, offload and decoder setup.

FP8 weights are a separate FastVideo variant; the FP8 recipe for RTX 4090 illustrates the non-FP4 path with layerwise offload and compatible BF16 encoder components. Use each runtime's matching checkpoint format.

Acknowledgements

FastH3 Omni was built in close collaboration with Nuva Lab, which co-developed the model with FastVideo, defined and curated the omni reference dataset, and brought production-grounded creative video workflows to FastH3. For dedicated production deployment, fine-tuning on your own data and a creative agent on top, see Nuva Lab's FastH3-Omni page.

Thanks also to the NVIDIA FastGen team.

License

Use of these weights is governed by the MiniMax-H3 Community License Agreement. Bundled ComfyUI tooling retains its own licenses in conversion/upstream/.