# ffmpeg

> Video conversion tool.
> More information: <https://ffmpeg.org>.

- Extract the sound from a video and save it as MP3:

`ffmpeg -i {{path/to/video.mp4}} -vn {{path/to/sound.mp3}}`

- Transcode a FLAC file to Red Book CD format (44100kHz, 16bit):

`ffmpeg -i {{path/to/input_audio.flac}} -ar 44100 -sample_fmt s16 {{path/to/output_audio.wav}}`

- Save a video as GIF, scaling the height to 1000px and setting framerate to 15:

`ffmpeg -i {{path/to/video.mp4}} -vf 'scale=-1:{{1000}}' -r {{15}} {{path/to/output.gif}}`

- Combine numbered images (`frame_1.jpg`, `frame_2.jpg`, etc) into a video or GIF:

`ffmpeg -i {{path/to/frame_%d.jpg}} -f image2 {{video.mpg|video.gif}}`

- Trim a video from a given start time mm:ss to an end time mm2:ss2 (omit the -to flag to trim till the end):

`ffmpeg -ss {{mm:ss}} -to {{mm2:ss2}} -i {{path/to/input_video.mp4}} -codec copy {{path/to/output_video.mp4}}`

- Convert AVI video to MP4. AAC Audio @ 128kbit, h264 Video @ CRF 23:

`ffmpeg -i {{path/to/input_video}}.avi -codec:a aac -b:a 128k -codec:v libx264 -crf 23 {{path/to/output_video}}.mp4`

- Remux MKV video to MP4 without re-encoding audio or video streams:

`ffmpeg -i {{path/to/input_video}}.mkv -codec copy {{path/to/output_video}}.mp4`

- Convert MP4 video to VP9 codec. For the best quality, use a CRF value (recommended range 15-35) and -b:v MUST be 0:

`ffmpeg -i {{path/to/input_video}}.mp4 -codec:v libvpx-vp9 -crf {{30}} -b:v 0 -codec:a libopus -vbr on -threads {{number_of_threads}} {{path/to/output_video}}.webm`
