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Most commonly I use ffmpeg to extract a slice of an audio or video file without re-encoding. In case it interests folks, I made a tool called ffslice to do thi

by jchook 2y ago

Most commonly I use ffmpeg to extract a slice of an audio or video file without re-encoding. In case it interests folks, I made a tool called ffslice to do this: https://github.com/jchook/ffslice/ https://github.com/jchook/ffslice/

npollock 2y ago
does the tool snap to I-frames when slicing?
- oguz-ismail 2y ago
  >without re-encoding What do you think?
- miles 2y ago
  I don't know about ffslice, but you can get frame-perfect slicing with minimal reencoding via LosslessCut's experimental "smart cut" feature[2] or Smart Media Cutter's[3] smartcut[4]. [1] https://github.com/mifi/lossless-cut https://github.com/mifi/lossless-cut [2] https://github.com/mifi/lossless-cut/issues/126 https://github.com/mifi/lossless-cut/issues/126 [3] https://smartmediacutter.com/ https://smartmediacutter.com/ [4] https://github.com/skeskinen/smartcut https://github.com/skeskinen/smartcut
  - xuhu 2y ago
    For some reason, when ffmpeg reencodes from 23.97fps h264 to the same fps and codec, the result looks choppy, like the shutter speed was halved or something. The smart lossless encoding you mentioned helps a lot here.
  - jchook 2y ago
    Excellent video snipping resources. I love HN for this.
- jchook 2y ago
  Yes, the tool snaps to I-frames when slicing. The `-c copy` flag ensures no re-encoding, and inherently limits cuts to keyframes. TBH it's an unfortunate side-effect sometimes as you cannot cut video or audio exactly where you want.