Video SFX
Generate sound effects, foley and ambience that follow the action in a video, from an optional prompt. The new sound replaces the video's own audio track.
The Video SFX node generates sound for a video: sound effects, foley and ambience that follow what happens on screen. It watches the clip, reads your optional prompt, and returns an MP4 with the generated sound. The node runs the MMAudio model.
The new sound replaces the audio track
Video SFX drops the video's original sound. To keep the original sound as well, wire the result and the original audio, for example from Extract Audio, into Merge Video & Audio.
When to use it
- Add foley or ambience to a silent generated video.
- Generate room tone, weather or other environmental sound for a short cinematic clip.
- Produce several alternate takes of the sound in one run, and keep the best one.
- Build a soundtrack in layers, with the effects from this node and the dialogue or music from other nodes.
To create a sound effect from a text description alone, without a video, use Text to Audio.
Quick start
Add the node
Press Tab on the canvas and choose Video › Sound for Video › Video SFX.
Connect the video
Wire the clip into the Video input. MP4, MOV and WebM clips of up to 300 seconds work.
Describe the sound
Type the sound in the prompt, for example rain on a metal roof. Leave the prompt blank for foley driven by the video alone.
Run it
Click Run on the node. The video with its new sound appears on the node.
Inputs
| Input | Accepts | What it does |
|---|---|---|
| Video | Video nodes, such as Generate Video and Upload Video | The clip that needs sound. Required. MP4 (H.264), MOV or WebM, up to 300 seconds. |
| Prompt | Text nodes, such as Text and Prompt | The sound to generate. A wired prompt replaces the prompt typed in the settings panel. |
| Negative | Text nodes | Sounds to exclude. |
The output, Video, is an MP4 with the generated sound. The original sound is dropped.
Settings
| Setting | What it does |
|---|---|
| Prompt | The sound you want, for example footsteps on dry leaves, rain on a metal roof or engine revving. Leave it blank for foley driven by the video alone. |
| Negative prompt | Sounds to exclude. The default is music, which keeps the result free of music. Clear the field if you want music as the sound. |
| Versions | How many takes to generate in one run, from 1 to 4. Each version uses a different seed, and the cost grows with each version. |
| CFG strength | Under Advanced. How strictly the model follows the prompt, from 1 (loose) to 10 (strict). The default is 4.5. |
| Inference steps | Under Advanced. From 10 (fast) to 50 (clean). The default is 25. |
| Seed | Under Advanced. Leave it blank, or enter -1, for a random seed. The same seed and the same inputs give the same result. With several versions, each version adds its number to the seed, so every take is repeatable and different. |
| Pre & post text | Text that is always added before and after the prompt. It is hidden from people who use your workflow as an app. See Prompt pre and post text. |
Credits
The price depends on the length of the input video, rounded up to a bucket, and on the number of versions. Nodaro measures the video automatically. If it cannot be measured, the price of the shortest bucket is used.
| Video length | Credits per version |
|---|---|
| Up to 8 seconds | 10 |
| Up to 15 seconds | 10 |
| Up to 30 seconds | 20 |
| Up to 60 seconds | 30 |
| Up to 120 seconds | 50 |
| Up to 300 seconds | 110 |
The total is the price per version times the number of versions. For example, a 12-second clip with 1 version costs 10 credits, a 31-second clip costs 30 credits, and a 60-second clip with 4 versions costs 120 credits.
Limits
- Formats: MP4 (H.264), MOV and WebM.
- Length: up to 300 seconds. A longer video is refused with the error
video_duration_exceeds_limit. - Versions: up to 4 per run.
- Resolution: up to 1080p is recommended. Larger videos are untested and take longer to process.
Tips
- Describe the sound, not the scene.
crackling fireworks better thancampfire scene. - Test on short clips. A clip of up to 15 seconds costs the same as a clip of 8 seconds, so iterate on short clips.
- Layer the sound. For effects over music, generate the effects here, then mix in the music with Merge Video & Audio or Mix Audio.
- Fix the seed to compare prompts. With a fixed Seed, the only change between two runs is your prompt.
Frequently asked questions
Related
Merge Video & Audio
Text to Audio
Mix Audio
Extract Audio
Generate Video
Last updated on
Edit Plan
Plan an edit from a recording's transcript. Tighten it, find short shareable clips or mark chapters, as an edit decision list that Apply EDL renders.
Merge Video & Audio
Add voiceover, music or sound effects to a video. Set each track's volume and start time, and keep, lower or mute the video's own sound.