OGM

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Direct Wikipedia Plug

OGM meaning Ogg Media File, was developed by Tobias Waldvogel. It is a container (for video, audio and subtitles), which can do a few things the AVI format cannot:

  • Chapter support
  • Vorbis audio support

Just like AVI, it also supports

  • multiple subtitle tracks
  • multiple audio tracks, of various formats (MP3, AC3, Vorbis (not in AVI), WAV)

It is supported in Windows with OggDS or RadLight Ogg Media filters which can also decode Theora video and on Unix-like systems with MPlayer.

OGM is, fundamentally, just a hack of the Ogg container format, which hasn't been designed to support files containing codecs not endorsed by Xiph Foundation. It is most likely going to be viewed as a temporary solution and will no longer be considered a current solution when other media container formats come to support the same services.

At first, a major drawback of OGM was that it was not open source even though it was based on and around an open source Ogg framework. Apparently, Tobias was embarrassed about the quick-hack quality of his code and wanted to improve it before releasing it to the keen eyes of the Ogg Vorbis team.

However, Tobias has now officially joined the Xiph.org team (Xiph created Ogg Vorbis) and donated all the code to his directshow filters, including OGM-format manipulation and playback, to their BSD-style opensource repository. It is available, though without documentation, in the "oggds" module in the Xiph source code repository.

OGM Media Files are used often with the XviD video compression, although once Theora is finished, it should be the best codec for the OGM format.

See also