MIME Types and File Extensions

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Revision as of 23:45, 15 May 2007 by Conrad (talk | contribs) (→‎.ogv - video/ogg: may contain skeleton, cmml)
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WARNING: this page is under development and discussion - none of this are currently official Xiph recommendations.

.ogg - application/ogg

  • can contain any logical bitstreams multiplexed together in an ogg container
  • has been defined as such in RFC 3534 http://www.ietf.org/rfc/rfc3534.txt
  • .ogg has traditionally been used for Ogg Vorbis files, so an important subpart of the ".ogg" files will be just Ogg Vorbis. Existing hardware in the wild looks only for .ogg and treats it as unmultiplexed Ogg Vorbis I.
  • .ogg has more recently also been used for Ogg FLAC and for Ogg Theora
  • apps supporting .oga, .ogv SHOULD support decoding from muxed Ogg streams
  • random multitrack files SHOULD contain a skeleton track to identify all containing logical bitstreams
  • apps that identify a logical bitstream which they cannot decode SHOULD drop but MAY still decode the ones they can

.oga - audio/ogg

  • audio in Ogg
    • Vorbis, Speex, FLAC, Ghost, OggPCM
    • May contain Ogg Skeleton and/or CMML logical bitstreams.

RATIONALE: This distinguishes audio-only files, using any of the Xiph audio codecs, from Ogg Vorbis I files (traditional .ogg) which may not contain more than one logical bitstream.

.ogv - video/ogg

  • a/v in Ogg
    • Theora, Theora + Vorbis, Theora + Speex, Theora + FLAC, Dirac + Vorbis, MNG + FLAC, Tarkin, OggUVS
    • May contain Ogg Skeleton and/or CMML logical bitstreams.

.spx - audio/ogg+speex

  • .spx has traditionally been used for Ogg Speex files and should be considered for backwards-compatibility

.flac - application/flac

  • flac in native encapsulation format


Codec MIME types

Codecs need their own MIME types for streaming and to be used in multitrack ogg files using skeleton:

  • audio/vorbis for Vorbis without container
  • video/theora for Theora without container
  • audio/speex for Speex without container
  • audio/flac for FLAC without container, but extra FLAC Ogg header (?)