ffmpeg

Industry standard video and audio encoder

Setup

Is CLI, but has ports to most languages, even WASM

brew install ffmpeg

Usage

To refer to input files in options, you must use their indices (0-based). E.g. the first input file is 0, the second is 1, etc. Similarly, streams within a file are referred to by their indices. E.g. 2:3 refers to the fourth stream in the third input file. Also see the Stream specifiers chapter.

As a general rule, options are applied to the next specified file.

Example

• To set the video bitrate of the output file to 64 kbit/s:

  ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi

• To force the frame rate of the output file to 24 fps:

  ffmpeg -i input.avi -r 24 output.avi

• To force the frame rate of the input file (valid for raw formats only) to 1 fps and the frame rate of the output file to 24 fps:

  ffmpeg -r 1 -i input.m2v -r 24 output.avi