Convert Video from Different Formats

By Xah Lee. Date: . Last updated: .

You need to have ffmpeg installed. It's usually installed on linux.

If you don't have ffmpeg, try avconv. For some years around 2015, avconv is rename of ffmpeg.

Convert mov to MP4

ffmpeg -f mov -i x.mp4

Note, .mov is Apple's movie format.

Convert webm to MP4

ffmpeg -f webm -i x.webm x.mp4

Note, .webm is Google's movie format.

Clip a Video

ffmpeg -ss 00:10:05 -i input.mp4 -to 00:13:50 -c copy output.mp4

-ss time_off
Set the start time offset
-to time_stop
Record or transcode stop time

Find Out What's Inside a Video Container

“.mp4”, “.mkv” etc are Video/audio container formats. They package together video file, audio files, and other files, of various formats into 1 file.

To find out what's inside, use ffprobe, e.g.

ffprobe file.mkv

Example output:

~/web/xahmusic_org/music/i $ ffprobe xx.mkv
ffprobe version 3.4 Copyright (c) 2007-2017 the FFmpeg developers
  built with Apple LLVM version 9.0.0 (clang-900.0.37)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/3.4 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-gpl --enable-libmp3lame --enable-libx264 --enable-libxvid --enable-opencl --enable-videotoolbox --disable-lzma
  libavutil      55. 78.100 / 55. 78.100
  libavcodec     57.107.100 / 57.107.100
  libavformat    57. 83.100 / 57. 83.100
  libavdevice    57. 10.100 / 57. 10.100
  libavfilter     6.107.100 /  6.107.100
  libavresample   3.  7.  0 /  3.  7.  0
  libswscale      4.  8.100 /  4.  8.100
  libswresample   2.  9.100 /  2.  9.100
  libpostproc    54.  7.100 / 54.  7.100
Input #0, matroska,webm, from 'xx.mkv':
    COMPATIBLE_BRANDS: iso6avc1mp41
    MAJOR_BRAND     : dash
    ENCODER         : Lavf57.83.100
  Duration: 00:05:04.90, start: 0.000000, bitrate: 1329 kb/s
    Stream #0:0: Video: h264 (Main), yuv420p(tv, bt709, progressive), 1280x720 [SAR 1:1 DAR 16:9], 29.97 fps, 29.97 tbr, 1k tbn, 59.94 tbc (default)
      HANDLER_NAME    : VideoHandler
      DURATION        : 00:05:04.871000000
    Stream #0:1(eng): Audio: vorbis, 44100 Hz, stereo, fltp (default)
      DURATION        : 00:05:04.903000000
f140.m4a vs m4a diff 2020-01-03 78kkt
f140.m4a vs m4a diff 2020-01-03

Put a Opus Audio into a .Webm Container

ffmpeg -i x.opus -c:a copy x.webm

Add Opus Audio into Existing Webm

ffmpeg -i y.webm -i x.opus -c:v copy -c:a copy x.webm

Extract Audio from Video

extract audio file inside file x.mp4 and name it x.m4a

ffmpeg -i x.mp4 -vn -acodec copy x.m4a

ffmpeg -f mp4 -i x.mp4 -vn -c:a copy x.m4a


ffmpeg -f mp4 -i x.mp4 -map 0:1 -c:a copy x.m4a

2018-11-26 thanks to harvhat and matthew skala

Syntax of ffmpeg

The general syntax of ffmpeg is:

ffmpeg options infile_options -i infileName outfile_options outfileName

-f fmt
force format fmt

Ffmpeg Manpage

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