Speex - Patent-free, lossy audio compression format designed for speech.

Opus - Open, royalty-free, lossy audio codec, designed for speech and general audio coding and low latency.

opencore-amr - Open source implementation of the Adaptive Multi Rate (AMR) speech codec.

Musepack (MPC) - Open source lossy audio codec, designed for transparency.

libdca - Free library for decoding DTS Coherent Acoustics streams.

liba52 - Free library for decoding ATSC A/52 (Dolby Digital) streams (lossy).

LAME - MP3 encoder and graphical frame analyzer.

CELT - Open, royalty-free lossy audio codec, optimized for low latency.

WavPack - Lossless audio compression format that also has a lossy hybrid mode.

Apple Lossless (ALAC) - A lossless audio compression codec developed by Apple and deployed on all of its platforms and devices.

See also Wikipedia:Comparison of audio coding formats. For example, MPlayer pulls in a large number of codecs as dependencies, and also has codecs built in. It is not always necessary to explicitly install codecs if you have installed a media player. Playing multimedia content requires two components: This article deals only with codecs and application backends see List of applications/Multimedia for a list of media players ( MPlayer, mpv and VLC are popular choices). In order to play encoded streams, users must ensure an appropriate codec is installed. In general, codecs are utilized by multimedia applications to encode or decode audio or video streams.

From Wikipedia, 'a codec is a device or computer program capable of encoding and/or decoding a digital data stream or signal.'

Codec pack h265