FFMPEG

extract audio

ffmpeg -i foo.mp4 foo.mp3

concat

docs

Mit files.txt in form von:

# this is a comment
file /path/to/file1.mp4
file /path/to/file2.mp4
file '/path/to/name with space.mp4'

Und dann:

ffmpeg -f concat -safe 0 -i files.txt -c copy output.mp4

timelapse

stack overflow

Man beachte insbesondere auch die Nachfragen und Kommentare.

STEP=15 # take every 15th frame
FRATE=60 # output framerate
ffmpeg -f concat -an -i files.txt -vf "framestep=$STEP,setpts=N/$FRATE/TB" -r $FRATE out.mp4

• -an to drop the audio stream
• -r to set the framerate

reduce size

crf-value of 40 shrinked my 2GB file to 60MB

ffmpeg -i in.mp4 -crf 35 out.mp4