Video Chroma Keyer
Select a screen color to remove from every sampled frame. Tune the color distance and soft edge, reduce color spill, blend small matte fluctuations between frames, and place the subject over a solid color or local image. Download the actual composited video and inspect its mask.
Key features
- Key green, blue or another selected screen color from a short video
- Tune tolerance and fractional edge softness independently
- Reduce the selected color's spill on visible subject pixels
- Smooth small frame-to-frame alpha fluctuations without trailing large edge moves
- Use a solid color or local PNG/JPEG/WebP image behind the subject
- Preview the grayscale matte and download a playable, silent WebM
How to use
- Choose a local MP4/WebM video up to eight seconds or generate the example.
- Set the screen color, tolerance, edge softness, spill and temporal smoothing.
- Choose a solid replacement color or upload a background image.
- Run the chroma key and inspect the original, result and matte preview.
- Download the composited WebM or adjust settings and run again.
Use cases
- Place a product presenter over a branded color
- Replace a blue screen with a local photograph
- Compare edge softness before sharing a clip
- Inspect green spill in a short training video
Frequently asked questions
Is this the same as AI background removal?
No. This tool keys pixels similar to a color you choose in each video frame. It needs a reasonably even screen. The separate background-remover handles one still image with an AI model.
What do tolerance, softness and spill change?
Tolerance removes colors close to the key; softness creates partly transparent edges. Spill reduces excess of the key's strongest RGB channel in visible subject pixels. High settings can remove clothing or change colors, so inspect the matte.
How is temporal flicker handled?
Small alpha changes at the same pixel are blended with the preceding frame. Large edge changes are left alone to avoid long trails. This is a simple temporal filter, not object tracking.
Can I export a transparent or audible video?
No. The WebM has the selected background baked in and is silent. Original audio, captions, alpha channel and metadata are not preserved. A grayscale matte is shown as a preview, not exported as a separate video.
Does the duration stay the same?
The tool samples at approximately 12 fps and checks that the recorded video's decoded duration is within 0.35 seconds of the input. Exact frame timing and codec depend on the browser.
What are the limits?
One local MP4/WebM up to 32 MiB and eight seconds, at most 8 million source pixels. Output is up to 480 × 270. Optional PNG/JPEG/WebP backgrounds are up to 8 MiB. Browser decode, canvas capture and WebM recording support are required.
Privacy
The video and optional background image are decoded and composited in this browser. Their bytes and frames are not uploaded to this tool's server or saved in browser storage. Clear the workspace to release media references.
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