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.
libvpx – VP8 and VP9 implementation; formerly a proprietary codec developed by On2 Technologies, released by Google under a BSD-like license in May 2010. Currently in use by the Chromium web browser.
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.)