This is a listing of open-source codecs—that is, open-source softwareimplementations of audio or video coding formats. Many of the codecs listed implement media formats that are restricted by patents and are hence not open formats. For example, x264 is a widely used open source implementation of the heavily patent encumbered MPEG-4 AVC video compression standard.
libvpx – VP8 and VP9 implementation; formerly a proprietary codec developed by On2 Technologies, released by Google under a BSD-like license in May 2010.
SVT-AV1 – An AV1 encoder originally developed by Intel and Netflix, which is available as FOSS now.[5] SVT-AV1 is generally considered to be the most optimized and fastest free AV1 encoder, which is why it serves as the base for the development of new, free, general-purpose and production-ready implementations in the AOMedia Software Implementation Working Group.[6] While SVT-AV1 already performs very well in constrained quality mode and is economically usable for many scenarios, as of the time being commercial implementations like Aurora1 may still beat it.[7]
VideoLANdav1d – An AV1 decoder for decoding videos with AV1 codec
xvc – An open source video codec, aiming to compete with h.265 and AV1. The reference implementation is released under the LGPL 2.1 and currently available in version 2.0 (as of 12/2020)[8]
FFmpeg codecs – Codecs in the libavcodec library from the FFmpeg project (FFV1, Snow, MPEG-1, MPEG-2, MPEG-4 part 2, MSMPEG-4, WMV2, SVQ1, MJPEG, HuffYUV and others). Decoders in the libavcodec (H.264, SVQ3, WMV3, VP3, Theora, Indeo, Dirac, Lagarith and others).
Lagarith – Video codec designed for strong lossless compression in RGB(A) colorspace (similar to ZIP/RAR/etc.)
Musepack – Lossy compression; based on MP2 format, with many improvements.
Speex – Low bitrate compression, primarily voice; developed by Xiph.Org Foundation. Deprecated in favour of Opus according to www.speex.org.
CELT – Lossy compression for low-latency audio communication
libopus – A reference implementation of the Opus format, the IETF standards-track successor to CELT. (Opus support is mandatory for WebRTC implementations.)
libvorbis – Lossy compression, implementation of the Vorbis format; developed by Xiph.Org Foundation.