If AVbin is not installed, only uncompressed RIFF/WAV files encoded with linear PCM can be read.
With AVbin, many common and less-common formats are supported. Due to the large number of combinations of audio and video codecs, options, and container formats, it is difficult to provide a complete yet useful list. Some of the supported audio formats are:
Some of the supported video formats are:
For a complete list, see the AVbin sources. Otherwise, it is probably simpler to simply try playing back your target file with the media_player.py example.
New versions of AVbin as they are released may support additional formats, or fix errors in the current implementation. AVbin is completely future- and backward-compatible, so no change to pyglet is needed to use a newer version of AVbin -- just install it in place of the old version.