15 second clip
ffmpeg -i in.mp4 -t 00:00:15 in_15s.mp4
clip to exact frames
ffmpeg.exe -i in.mp4 -vf "select=between(n\,100\,395),setpts=PTS-STARTPTS" -an out.mp4
resize 640 width, keep aspect ratio
ffmpeg -i in.mp4 -vf "scale=640:-1" in_640w.mp4
convert to mp4
ffmpeg -i in.avi -c:v libx264 in.mp4
convert to mp4 high quality
ffmpeg -i in.avi -c:v libx264 -crf 18 in_hq.mp4
create loop by playing video backwards at end
ffmpeg -i in.mp4 -filter_complex "[0]reverse[r];[0][r]concat=n=2:v=1:a=0" in_rev_loop.mp4
reverse video
ffmpeg -i in.mp4 -vf reverse in_rev.mp4
512x512 crop center
ffmpeg -i in.mp4 -vf "scale='if(lte(iw,ih),512,-1)':'if(lte(ih,iw),512,-1)',crop=512:512" in_512w_512h.mp4
video to image sequence
ffmpeg.exe -i in.mp4 "out_%d.png"
convert to mp3
ffmpeg -i in.wav -n -codec:a libmp3lame -q:a 1 in.mp3
remove audio
ffmpeg -i in.mp4 -c copy -an in_silent.mp4