Sample ffmpeg Commands

Convert to 480p

$ ffmpeg -i input.mp4 -s hd480 -c:v libx264 -crf 23 -c:a aac -strict -2 output.mp4

Convert to 720p via scaling, copy audio

$ ffmpeg -i input.mp4 \
  -c:v libx264 -preset medium -tune film -crf 22 -vf scale=-1:720 \
  -c:a copy \
  output.mp4

Convert to 720p via scaling, encode 128kbit audio

$ ffmpeg -i input.mp4 \
  -c:v libx264 -preset medium -tune film -crf 22 -vf scale=-1:720 \
  -c:a libfdk_aac -b:a 128k \
  output.mp4

-preset Options

Set the encoding speed to compression ratio. Faster compression yields a larger file.

  • ultrafast
  • superfast
  • veryfast
  • faster
  • fast
  • medium
  • slow
  • slower
  • veryslow

Making Clips

$ ffmpeg -i input.mov \
  -ss 00:00:05.00 \
  -to 00:23:25.17 \
  -c copy \
  -avoid_negative_ts 1 \
  clip.mov

Joining Clips

# files.txt
file 'clip1.mov'
file 'clip2.mov'
file 'clip3.mov'

$ ffmpeg -f concat -i files.txt -c copy output.mov

Replacing Audio

$ ffmpeg -i OriginalVideo.mp4 -i NewAudio.wav -acodec copy -vcodec copy -map 0:v -map 1:a Output.mp4

wav to flac

$ find /Volumes/128GB_MSD/_archive/tycho-epoch-wav -type f -iname "*.wav" -exec sh -c \
'bn=${1##*/}; bn=${bn%.*}; ffmpeg -loglevel 16 -i "$1" "${0}${bn}.flac"' /Volumes/128GB_MSD/_archive/tycho-epoch/ {} \;

References