This GStreamer plugin supports a large number of audio and video compression formats through the use of the ffmpeg library. The plugin contains GStreamer elements for encoding 40+ formats (MPEG, DivX, MPEG4, AC3, DV, ...), decoding elements for decoding 90+ formats (AVI, MPEG, OGG, Matroska, ASF, ...), demuxing 30+ formats and colorspace conversion.

http://www.ffmpeg.org/ http://gstreamer.freedesktop.org/ http://gstreamer.freedesktop.org/modules/gst-libav.html