List of open source codecs

This is a listing of open-source implementations of media formats—usually called codecs. Many of the codecs listed implement media formats that are restricted by patents and are henceforth not open formats. For example, x264 is a widely used open source implementation of the heavily patent encumbered MPEG-4 AVC media format.

Video codecs

• x264 - H.264/MPEG-4 AVC implementation. x264 is not a codec (encoder/decoder), it is just an encoder (it cannot decode video).
• Xvid - MPEG-4 Part 2 codec, compatible with DivX
• libvpx - VP8 implementation; formerly a proprietary codec developed by On2 Technologies, released by Google under a BSD-like license in May 2010.^[1][2][3][4]
• FFmpeg codecs - Codecs in the libavcodec library from the FFmpeg project (FFV1, Snow, MPEG-1, MPEG-2, MPEG-4 part 2, MSMPEG-4, WMV2, SVQ3, MJPEG, HuffYUV and others). Decoders in the libavcodec (H.264, WMV3, VP3, Theora, Indeo and others).
• Lagarith - Video codec designed for strong lossless compression in RGB(A) colorspace (similar to ZIP/RAR/etc.)
• libtheora - A reference implementation of the Theora format, based on VP3, part of the Ogg Project
• Tarkin - An experimental and now obsolete lossy video codec formerly under development by the Xiph.org Foundation, replaced by Theora
• dirac-research - A wavelet based codec created by the BBC Research. It is the software reference implementation of Dirac.
• Schrödinger - A Dirac implementation developed by David Schleef.^[5]
• Huffyuv - Lossless codec from BenRG
• OpenAVS - Audio Video Standard (AVS) codec with 90% of its patents owned by Chinese companies and government.

Audio codecs

• FLAC - Lossless compression.
• LAME - Lossy compression (MP3 format).
• TooLAME - Lossy compression (MP2 format).
• Musepack - Lossy compression; based on MP2 format, with many improvements.
• Speex - Low bitrate compression, primarily voice; developed by Xiph.org.
• CELT - Lossy compression for low-latency audio communication
• Opus - The IETF standards-track successor to CELT
• libvorbis - Lossy compression, implementation of the Vorbis format; developed by Xiph.org.
• iLBC - Low bitrate compression, primarily voice
• iSAC - Low bitrate compression, primarily voice; (free when using the WebRTC codebase)
• TTA - Lossless compression
• WavPack - Hybrid lossy/lossless
• Apple Lossless - Lossless compression (MP4)
• OpenAVS
• FFmpeg - Codecs in the libavcodec library from the FFmpeg project (e.g. AC-3, AAC, ADPCM, PCM, Apple Lossless, FLAC, WMA, Vorbis, MP2, etc.)
• FAAD2 - open-source decoder for Advanced Audio Coding. There is also FAAC, the same project's encoder, but it is proprietary (but still free of charge).
• libgsm - Lossy compression (GSM 06.10)^[6]
• opencore-amr - Lossy compression (AMR and AMR-WB)^[7]
• liba52 - a free ATSC A/52 stream decoder (AC-3)^[8]
• libdca - a free DTS Coherent Acoustics decoder^[9]
• Aften - Lossy compression (AC-3 format).

Text Codecs

(generally used for subtitles/closed captioning)

• Writ
• Kate

See also

Free software portal

• FFmpeg, cross-platform, open source, audio and video codecs suite/library
• List of multimedia (audio/video) codecs
  • Comparison of video codecs
  • Comparison of audio codecs
• List of other software video players
• List of other software media players
• Comparison of media players
• Free file format
• Comparison of video encoders

References

1. ^ "WebM Code - Build Prerequisites". http://www.webmproject.org/code/build-prerequisites/. Retrieved 2010-06-02. 
2. ^ "WebM Downloads". http://code.google.com/p/webm/downloads/list. Retrieved 2010-06-02. 
3. ^ "Introducing WebM, an open web media project". 2010-05-19. http://webmproject.blogspot.com/2010/05/introducing-webm-open-web-media-project.html. Retrieved 2010-05-19. 
4. ^ "WebM FAQ". 2010-05-19. http://www.webmproject.org/about/faq/. 
5. ^ "Schrodinger FAQ". http://diracvideo.org/schrodinger-faq/. Retrieved 2011-03-05. 
6. ^ Jutta Degener (2006-03). "GSM 06.10 lossy speech compression". http://user.cs.tu-berlin.de/~jutta/toast.html. Retrieved 2009-11-04. ^{[dead link]}
7. ^ "opencore-amr". 2009-09-18. http://sourceforge.net/projects/opencore-amr/. Retrieved 2009-11-04. 
8. ^ "liba52 - a free ATSC A/52 stream decoder". 2006-10-03. http://liba52.sourceforge.net/. Retrieved 2009-11-04. 
9. ^ "libdca - a free DTS Coherent Acoustics decoder". 2009-02-19. http://www.videolan.org/developers/libdca.html. Retrieved 2009-11-04.