StudyKit browser utility

Video Auto Clip

Point it at a video and it finds every place the picture cuts to a new shot, then writes each of those shots out as its own MP4. The file is read, measured and rewritten inside this page.

1. Choose a video

Your video is opened by this page alone. It is never sent anywhere, and closing the tab forgets it.

Choose a video, or drop one here You can also paste a video with Ctrl or Command and V MP4 or WebM, up to 2 minutes

Choose a video to begin. Nothing is uploaded.

2. Where it would cut

The video will appear here as a strip of frames, with a line at every scene change.

Cutting a video means rebuilding it. Almost every video stores each frame as a small change on top of the frames before it, so a clip cannot simply be lifted out of the middle of one. Each part has to be decoded and encoded again, which is why there is a progress bar and why this step takes longer than the scan. The clips are new files at the chosen picture quality, not copies of the original with a few bytes removed, so their real size is measured and shown.

How scene detection works, and when it gets it wrong

What it measures

Every frame is reduced to a 64 by 36 thumbnail and compared with the frame before it. The score is how much the colour changed, measured across all three channels. A cut in the picture is a large score; ordinary movement inside a shot is a small one.

Why the threshold moves

There is no single number that works everywhere. A locked-off tripod shot barely changes between frames; a handheld one changes constantly. The tool takes its threshold from your own video’s typical frame-to-frame change, then raises it, so it adapts instead of guessing.

Cuts it finds

Hard changes of shot, a switch between two cameras, a cut from indoors to outdoors. Two cuts less than half a second apart are treated as one, so a flash or a strobe does not shred the file.

Cuts it misses

Dissolves and fades, because the change is gradual rather than abrupt. Two different shots that look nearly identical, such as two angles on the same white wall. A slow pan across a busy scene. For those, this tool is the wrong one.

Why there is a two minute limit

Re-encoding is the slow half, and it happens in your browser. Two minutes is roughly a minute of work on ordinary hardware. A longer video is a job for a desktop editor with a hardware encoder, not for a web page.

Sound and silence

Each clip carries the sound from the part of the original it came from, re-encoded alongside the picture so the two stay lined up. Turning sound off makes the files smaller and the encode faster. Detecting long silences and trimming them out is a different job and not something this tool attempts.

What you get at the end

One MP4 per shot, each starting at zero so it plays on its own. If the video turned out to be a single shot, you get that one file directly. If there is more than one, they arrive together in a ZIP, because a page that starts a separate download for each part gets some of them blocked by the browser.