Cut one long recording into clips. Pick how the cuts are made, see the pieces listed and marked on the timeline, choose whether they are copied or re-encoded, and export them all in one run.
Four ways to cut
- Equal parts splits the range into N pieces of the same length.
- Every N seconds makes a piece of that length from the start, and a shorter last piece from what remains.
- At times cuts at the seconds you type, separated by commas. Add a cut at the playhead to place one while watching.
- At scene changes reads the video once and proposes a cut wherever the picture changes abruptly. The sensitivity slider decides how abrupt: 1 keeps only hard cuts, 10 also catches dissolves and camera moves.
The in and out handles limit the split to part of the video. The pieces list under the controls shows every piece’s start, end, and length before anything is exported.
Copy vs re-encode
Compressed video stores a full picture only every so often, at key frames, and the frames between are stored as changes from earlier ones. A piece that is copied rather than re-encoded has to begin on a key frame.
Key frame cuts snap each cut to the nearest key frame. The pieces are bit for bit the source, they meet exactly, and a two-hour file splits in the time it takes to read it. The cost is precision, up to a second or two on phone footage and more on screen recordings, which the timeline markers show before export.
Exact frame decodes each piece and re-encodes it, so the cuts land where you set them. It takes about as long as playing the whole video, and the picture goes through one more generation of compression.
Use key frame to break a long recording into chapters. Use exact frame when a cut has to land on a word or a beat.
Scene detection
Each frame is decoded at 96 pixels wide, and the mean difference in brightness from the previous frame is recorded. A cut is claimed where that difference clears the sensitivity threshold and also stands well above the differences of the frames before it, so a shot with fast motion, which raises every difference, is not chopped up. Two cuts closer than half a second count as one.
The scan is one pass over the file at a small size, which runs faster than playback. The sensitivity re-filters the recorded differences without reading the file again.
Audio
Each piece keeps its share of the soundtrack. A key frame cut copies the audio packets from the same point; an exact cut decodes the audio and cuts it on the sample. Remove audio exports silent pieces.
Output
The pieces keep the source container and are named name-part-01, name-part-02, and so on. The result reports how many pieces were made, their total size, and whether the video was copied or encoded. Pieces are written to browser storage as they finish and stay there until the next export or until the page is left.