How to Split a Video With FFmpeg (Why -c copy Ignores Your Segment Time, N Equal Parts, Scene Cuts, and a pytest Check)
Short answer: to split a video with FFmpeg, use the segment muxer: ffmpeg -i input.mp4 -map 0 -c copy -f segment -segment_times 4.041667,7.083333 -reset_timestamps 1 part_%03d.mp4 That is lossless and fast, but with -c copy FFmpeg can only cut on keyframes , so -segment_time 2 does not mean "2-second parts". If you need exact lengths you must re-encode and force a keyframe at every boundary.…
FFmpeg is a powerful tool for splitting videos, but it requires a specific command to achieve exact segment lengths without using the lossless and fast -c copy method. This command must include the segment muxer, specify the segment times, reset timestamps, and output the parts with sequential numbering.
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