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Specification of MIME Types and of codecs parameters

MIME Types

The following MIME types are now officially registered with IANA (well, almost, see [[1]]):

  • application/ogg - for complex, multitrack, multiplexed files encapsulated in Ogg
    • requires a Skeleton logical bitstream
  • video/ogg - for video encapsulated in Ogg
    • recommends a Skeleton logical bitstrem
  • audio/ogg - for audio encapsulated in Ogg
    • recommends a Skeleton logical bitstrem

Other MIME types are still in the process.

Codecs Parameter

| Typically, MIME types of media encapsulation formats use the optional "codecs" parameter to specify which codes are being used in a particular file.

Codecs encapsulated in Ogg require a text identifier at the beginning of the first header page to identify the encapsulated codecs. The following table contains the identifiers for existing Xiph codecs and the codecs parameter names used for */ogg MIME types (in alphabetical order):

Codecs Parameter Name Codec Identifier (decimal) Codec Identifier (hex) Codec Identifier (octal) Version Field (if available)
dirac] char[0,5]: 'BBCD\0' '0x42 0x42 0x43 0x44 00' '0102 0102 0103 0104 0000'  ??
flac] char[0,5]: '\177FLAC' '0x7F 0x46 0x4C 0x41 0x43' '0177 0106 0114 0101 0103' char[5,1]: binary major version number,

char[6,1]: binary minor version number of mapping

midi] char[8]: 'OggMIDI\0'
speex] char[0,8]: 'Speex ' '0x53 0x70 0x65 0x65 0x78 0x20 0x20 0x20' '0123 0160 0145 0145 0170 0040 0040 0040' char[8,24]: version field,

char[24,4]: version id

theora] char[0,7]: '\x80theora' '0x80 0x74 0x68 0x65 0x6f 0x72 0x61' '0180 0164 0150 0145 0157 0162 0141' char[7,1]: major version number,

char[8,1]: minor version number, char[9,1]: version revision number

vorbis] char[0,7]: '\x01vorbis' '0x01 0x76 0x6f 0x72 0x62 0x69 0x73' '0001 0166 0157 0162 0142 0151 0163' char[7,4]: version field
       Codec Identifier             | Codecs Parameter
       char[8]: 'OggMIDI\0'         | midi
       char[8]: 'CMML\0\0\0\0'      | cmml
       char[8]: '\211PNG\r\n\032\n' | png
       char[8]: '\212MNG\r\n\032\n' | mng
       char[8]: '\213JNG\r\n\032\n' | jng
       char[8]: 'CELT    '          | celt
       char[8]: 'PCM     '          | pcm
       char[9]: '\x80kate\0\0\0\0'  | kate
       char[9]: 'YUV4MPEG2'         | yuv4mpeg