HunyuanVideo-Foley | video to audio Foley generation

HunyuanVideo-Foley is a text-video-to-audio system from Tencent that generates synchronized Foley, ambience, and incidental sounds from picture at 48 kHz stereo. Feed it a clip and it produces timing aware effects that follow the visual action without manual spotting.

You can steer the output with short prompts describing space, distance, and material. Without prompts, the model generates a baseline pass from visual content alone, which gives you a starting reference before you add any direction.

What the System Does

HunyuanVideo-Foley identifies visual events in a clip, footsteps, impacts, cloth movement, door interactions, background environment sound sources, and generates corresponding audio effects timed to those events at the correct frame positions. The model is trained on video-audio pairs to associate visual motion with the sounds that typically accompany it.

The output is a 48 kHz stereo WAV file that is directly compatible with standard post audio workflows. No sample rate conversion is needed before bringing the output into a DAW or NLE sound track.

At 48 kHz stereo, the output format matches broadcast delivery specifications and professional DAW project settings. The files can be placed directly into sound tracks without format conversion, which removes one friction point from the temp audio workflow.

Why the Output Format Matters for Post

Most AI audio generation tools produce mono output or low sample rates that require post processing before they are usable in a professional context. 48 kHz stereo puts HunyuanVideo-Foley's output in the same format as professional library sound effects and location audio, so you can mix it directly alongside real recorded elements without conversion artifacts.

The audio can be split into stems per scene rather than collapsed into a single stereo file. Keeping Foley, ambience, and effect stems separate gives your final mix engineer headroom to balance and dynamics-process each element independently, which is how professional sound post-production is structured.

This also means the temp audio that HunyuanVideo-Foley generates can be referenced directly by the sound team during the final mix. If a generated effect works, the sound team can replicate or replace it; if it does not, the stem makes it easy to identify and remove. The temp track becomes a useful communication tool rather than an artifact that has to be completely discarded.

Prompt-Guided Generation

Prompts are optional but meaningfully useful when you need specific results. The most effective prompts describe three properties: space, material, and distance. "Concrete floor, footsteps, close interior" produces a different result than "gravel exterior, footsteps, medium distance" even if the visual content is the same person walking.

Write prompts that sound like mix notes rather than descriptions of the visual scene. "Warehouse reverb, metal impact, resonant" gives the model enough acoustic context to generate something that matches the intended environment rather than the literal content of the frame.

The model responds to both positive prompts and negative prompts. If you receive a result with unwanted elements, adding a negative prompt for those elements in the next generation pass can clean up the output without a full restart. This is particularly useful for ambience generation where broad environmental sounds may include frequency ranges you do not want.

Prompt iteration is fast. Start with a simple prompt, evaluate the output, and refine the language for specific frequency content, room size, or material texture. Three or four iterations typically narrow the result to the intended target.

Practical Use Cases for Post

The most immediate use case is temp Foley for rough cuts and editorial reviews. When a cut goes into review, having any sound on picture, even rough temp effects, dramatically changes how the audience evaluates pacing, rhythm, and performance. HunyuanVideo-Foley replaces the silence that would otherwise require either a sound supervisor present at the cut review or a pass of manual library spotting before the session.

Animatics and previs are a second major application. Early stage animation and visualization material is almost always silent because the sound department has not started work. HunyuanVideo-Foley can add a sound pass to animatics that makes them dramatically more communicative to directors, producers, and clients who are evaluating whether the visual sequence reads.

Batch processing of dailies is a third use case. When large volumes of footage need any form of sound reference attached for editorial review, running the footage through HunyuanVideo-Foley is much faster than manual spotting. The resulting files are rough references, not final sounds, but they make editorial review of silent dailies significantly more useful.

Workflow Integration Tips

Save multiple versions per shot at different prompt settings rather than committing immediately to a single output. Two or three versions labeled clearly by prompt variant give your editor or director the ability to audition options directly in the NLE without going back to generation.

Render by scene rather than by full reel when you are generating for a dramatic sequence. Processing scene by scene allows you to tune the prompts to the specific environment of each scene, which produces better consistency than applying one setting across an entire reel with multiple locations.

Keep a style sheet per project that records your default room tone decisions, perspective rules, and prompts for recurring environments. When you return to the same location or set in a later sequence, matching the prompt to the established style sheet keeps the audio universe consistent across the cut.

When you hand off to final sound, share your prompts, seeds, and version information with the sound supervisor. This gives them a direct reference for what you intended when generating temp effects and allows them to either match, replace, or explicitly deviate from the temp aesthetic with a documented decision.

Quality and Known Limitations

HunyuanVideo-Foley is trained on video and audio correspondences rather than on fine grained acoustic physics simulation. It will generate plausible sounds for common visual events but may produce less accurate results for specialized or unusual sound sources that appear rarely in training data.

Very fast motion, highly textured surfaces, or unusual material interactions may produce outputs that are plausible sounding but not acoustically accurate. This is expected behavior for any learned correspondence model and does not represent a failure of the system, just a limit on what should be used as a final delivery asset.

Dialogue is entirely outside the model's scope. HunyuanVideo-Foley generates Foley and ambience, not speech. Any scene with speaking characters requires ADR, sync sound, or a separate voice processing pipeline for the dialogue tracks. Plan the sound department workflow to handle dialogue separately from the Foley generation pass.

License and Commercial Deployment

HunyuanVideo-Foley is released with a Tencent Hunyuan Community License. The weights are openly downloadable for research and evaluation, but this is not a permissive open source license. Commercial use is allowed under conditions that may include territory limits and scale thresholds.

Always read the current license in the model card and repository before integrating the tool into a paid workflow. The license terms are subject to update, and the version at time of your integration may differ from the version at time of this article's publication.

If you operate across multiple regions, confirm whether your markets are fully covered under the current terms. Some Tencent Hunyuan community license versions include territory-specific restrictions that affect distribution and revenue-generating uses. A legal review of the specific license version is advisable before production deployment.

For composition and music rather than picture synced Foley, Stable Audio 3 covers six minute song generation and sound effects under the Stability AI Community License with licensed training audio.

The Promptless Baseline Pass

One of the more useful characteristics of HunyuanVideo-Foley is that it generates a baseline audio pass from visual content alone when no prompt is provided. This baseline reflects what the model has learned about the acoustic correlates of the visual events in the clip, without any explicit direction about what the space should sound like.

The baseline pass is valuable as a diagnostic. Before spending time writing prompts, run a promptless pass to understand what the model naturally generates for your footage. If the baseline is close to what you want, a short prompt that adjusts one or two elements, such as room size or material, is often sufficient. If the baseline is far from the target, the gap tells you specifically what the model got wrong and where your prompts need to provide correction.

Many practitioners find that the promptless baseline is usable for a significant portion of their shots without modification. Shots with common visual events, footsteps on hard surfaces, object interactions, door sounds, produce reliable baselines because those events are well represented in the model's training data. Unusual events, specific acoustic environments, or highly stylized sound design requirements are where prompts become essential.

Run the promptless baseline as the first step of any generation session before investing time in prompt writing. Use the baseline results to identify which shots need active guidance and which can be used directly or with minimal adjustment.

Testing with the HuggingFace Space

The Tencent HuggingFace Space for HunyuanVideo-Foley provides a browser-based testing interface that allows you to evaluate the model on your own clips before setting up local infrastructure.

The Space interface accepts video uploads and optional text prompts and returns generated audio that you can download. For quick evaluation of whether the model is suitable for your project, this is the fastest starting point. You do not need a local GPU, no installation, and no configuration. Upload a representative clip, run with and without a prompt, and evaluate whether the results meet your quality bar.

The Space may require a short loading time if it has been inactive, but once loaded it processes clips at speeds suited to the interactive evaluation use case. Once you have confirmed through the Space that the model works for your material and that the output format fits your pipeline, set up local inference for batch processing at production scale. Local inference will be significantly faster for large clip volumes than browser-based generation, even though the model quality is identical.

Keep in mind that clips uploaded to a public Hugging Face Space are transmitted to Tencent servers for processing. For proprietary footage or confidential production materials, use local inference from the beginning rather than the public Space interface.

Integrating Foley AI into a Sound Post Workflow

HunyuanVideo-Foley fits most naturally into the first pass of sound post, the phase where picture locked footage gets a complete audio reference before final sound design begins. At this stage, the goal is to replace silence with something that allows editorial and director review of the cut as a fully realized piece rather than a silent timing exercise.

The generated Foley does not need to be final to be useful. A plausible footstep is better than no footstep when reviewing whether a scene's pacing is working. A credible ambient room tone is better than silence when evaluating whether the emotional register of a scene is landing. The AI generation gives the review process enough audio information to make meaningful creative decisions.

From that first pass, the sound supervisor can evaluate which generated elements are close enough to use as-is in the temp mix, which need replacement with library material, and which scenes require original recording. This evaluation is faster and more meaningful when conducted against AI generated audio than against silence.

The final delivery asset is always a professional mix from your DAW, with EQ, dynamics processing, and format specific encoding applied. The AI generated Foley is part of the creative reference and workflow efficiency, not the delivery file. Keep that separation clear in your production pipeline so there is no ambiguity about what exits the project for broadcast or theatrical delivery.

For independent and documentary productions where a full sound department is not available throughout post, AI Foley generation changes what is achievable without a spotting session. A filmmaker who can run HunyuanVideo-Foley overnight on their footage and arrive at an editorial review with sound on picture has better creative context for the cut they are evaluating than one who attends a silent cut review.

The AI FILMS Studio sound workspace provides browser-based access to AI sound and music generation for teams who want to add ambient music and general sound design alongside picture synced Foley in a single integrated workflow.

The combination of picture synced Foley from HunyuanVideo-Foley and music generation from a dedicated audio tool gives a post production team a complete temp sound pass from AI sources, covering ambience, effects, and underscore from the same picture cut before any studio session is booked.

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Sources

HuggingFace: tencent/HunyuanVideo-Foley GitHub: Tencent-Hunyuan/HunyuanVideo-Foley HuggingFace Space: tencent/HunyuanVideo-Foley arXiv: 2508.16930