FFmpeg

FFmpeg is a cross platform, free, open source media encoder/decoder toolkit. It contains the programs and libraries necessary to convert audio and video into a wide range of formats. FFmpeg was written by Fabrice Bellard (creator of QEMU and BPG).

USE flags
The above list is non-comprehensive. Use equery (part of ) to see all available flags:

Emerge
After setting appropriate USE flags, emerge FFmpeg:

Configuration
This section needs some help.

Media player (ffplay)
FFmpeg comes with a built-in command line media player called ffplay.

For more information consult the following commands:

External resources

 * FFmpeg Wiki
 * [HOWTO using ffplay as your default player for audio/video]