Video Editor
A collection of local tools for cutting, compressing, watermarking, changing the speed of, transforming, and stitching videos.
How to use video editing
Video files are processed only in the current browser through the local media runtime; nothing is uploaded, no remote transcoding service is contacted, and the input is not saved.
Select an action
Choose operations such as cutting, compression, watermarking, speed adjustment, transformation, or merging, and read the corresponding parameter descriptions.
Load video
After selecting a local video, wait for media detection to finish, then confirm that its magic number, duration, dimensions, and codec are within the limits.
Preview export
Run allowlisted operations, check the output playback, dimensions, and duration, then download it; if it fails, retain the reason for the error.
Limitations and Notes
- Video editing uses the browser Canvas, MediaRecorder, and Web Audio; processing large files uses more memory and is limited by the encoding capabilities of the current browser.
- Corrupted, oversized, excessively long, or unsupported-codec videos will be rejected and will not fall back to a remote service.
- Watermarking, compression, and stitching results may be affected by the source file’s encoding. Verify them in the target player before official release.
FAQ
Will the video be uploaded to a server?
No. Detection, editing, and exporting are all completed in the current browser.
Why is processing so slow?
The browser must render and re-encode the video frame by frame locally, so large files take more time.
Are all video formats supported?
Not supported; the page validates each item against the input magic number, media detection, and the operation allowlist.