#------------------------------------------------------------------------------
# $File: vorbis,v 1.26 2020/08/22 18:30:55 christos Exp $
# vorbis: file(1) magic for Ogg/Vorbis files
#
# From Felix von Leitner <leitner@fefe.de>
# Extended by Beni Cherniavsky <cben@crosswinds.net>
# Further extended by Greg Wooledge <greg@wooledge.org>
#
# Most (everything but the number of channels and bitrate) is commented
# out with `##' as it's not interesting to the average user. The most
# probable things advanced users would want to uncomment are probably
# the number of comments and the encoder version.
#
# FIXME: The first match has been made a search, so that it can skip
# over prepended ID3 tags. This will work for MIME type detection, but
# won't work for detecting other properties of the file (they all need
# to be made relative to the search). In any case, if the file has ID3
# tags, the ID3 information will be printed, not the Ogg information,
# so until that's fixed, this doesn't matter.
# FIXME[2]: Disable the above for now, since search assumes text mode.
#
# --- Ogg Framing ---
#0 search/1000 OggS Ogg data
0 string OggS Ogg data
>4 byte !0 UNKNOWN REVISION %u
##>4 byte 0 revision 0
>4 byte 0
##>>14 lelong x (Serial %lX)
# non-Vorbis content: FLAC (Free Lossless Audio Codec, http://flac.sourceforge.net)
>>28 string \x7fFLAC \b, FLAC audio
# non-Vorbis content: Theora
!:mime audio/ogg
>>28 string \x80theora \b, Theora video
!:mime video/ogg
# non-Vorbis content: Kate
>>28 string \x80kate\0\0\0\0 \b, Kate (Karaoke and Text)
!:mime application/ogg
>>>37 ubyte x v%u
>>>38 ubyte x \b.%u,
>>>40 byte 0 utf8 encoding,
>>>40 byte !0 unknown character encoding,
>>>60 string >\0 language %s,
>>>60 string \0 no language set,
>>>76 string >\0 category %s
>>>76 string \0 no category set
# non-Vorbis content: Skeleton
>>28 string fishead\0 \b, Skeleton
!:mime video/ogg
>>>36 leshort x v%u
>>>40 leshort x \b.%u
# non-Vorbis content: Speex
>>28 string Speex\ \ \ \b, Speex audio
!:mime audio/ogg
# non-Vorbis content: OGM
>>28 string \x01video\0\0\0 \b, OGM video
!:mime video/ogg
>>>37 string/c div3 (DivX 3)
>>>37 string/c divx (DivX 4)
>>>37 string/c dx50 (DivX 5)
>>>37 string/c xvid (XviD)
# --- First vorbis packet - general header ---
>>28 string \x01vorbis \b, Vorbis audio,
!:mime audio/ogg
>>>35 lelong !0 UNKNOWN VERSION %u,
##>>>35 lelong 0 version 0,
>>>35 lelong 0
>>>>39 ubyte 1 mono,
>>>>39 ubyte 2 stereo,
>>>>39 ubyte >2 %u channels,
>>>>40 lelong x %u Hz
# Minimal, nominal and maximal bitrates specified when encoding
>>>>48 string <\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff \b,
# The above tests if at least one of these is specified:
>>>>>52 lelong !-1
# Vorbis RC2 has a bug which puts -1000 in the min/max bitrate fields
# instead of -1.
# Vorbis 1.0 uses 0 instead of -1.
>>>>>>52 lelong !0
>>>>>>>52 lelong !-1000
>>>>>>>>52 lelong x <%u
>>>>>48 lelong !-1
>>>>>>48 lelong x ~%u
>>>>>44 lelong !-1
>>>>>>44 lelong !-1000
>>>>>>>44 lelong !0
>>>>>>>>44 lelong x >%u
>>>>>48 string <\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff bps
# -- Second vorbis header packet - the comments
# A kludge to read the vendor string. It's a counted string, not a
# zero-terminated one, so file(1) can't read it in a generic way.
# libVorbis is the only one existing currently, so I detect specifically
# it. The interesting value is the cvs date (8 digits decimal).
# Post-RC1 Ogg files have the second header packet (and thus the version)
# in a different place, so we must use an indirect offset.
>>>(84.b+85) string \x03vorbis
>>>>(84.b+96) string/c Xiphophorus\ libVorbis\ I \b, created by: Xiphophorus libVorbis I
>>>>>(84.b+120) string >00000000
# Map to beta version numbers:
>>>>>>(84.b+120) string <20000508 (<beta1, prepublic)
>>>>>>(84.b+120) string 20000508 (1.0 beta 1 or beta 2)
>>>>>>(84.b+120) string >20000508
>>>>>>>(84.b+120) string <20001031 (beta2-3)
>>>>>>(84.b+120) string 20001031 (1.0 beta 3)
>>>>>>(84.b+120) string >20001031
>>>>>>>(84.b+120) string <20010225 (beta3-4)
>>>>>>(84.b+120) string 20010225 (1.0 beta 4)
>>>>>>(84.b+120) string >20010225
>>>>>>>(84.b+120) string <20010615 (beta4-RC1)
>>>>>>(84.b+120) string 20010615 (1.0 RC1)
>>>>>>(84.b+120) string 20010813 (1.0 RC2)
>>>>>>(84.b+120) string 20010816 (RC2 - Garf tuned v1)
>>>>>>(84.b+120) string 20011014 (RC2 - Garf tuned v2)
>>>>>>(84.b+120) string 20011217 (1.0 RC3)
>>>>>>(84.b+120) string 20011231 (1.0 RC3)
# Some pre-1.0 CVS snapshots still had "Xiphphorus"...
>>>>>>(84.b+120) string >20011231 (pre-1.0 CVS)
# For the 1.0 release, Xiphophorus is replaced by Xiph.Org
>>>>(84.b+96) string/c Xiph.Org\ libVorbis\ I \b, created by: Xiph.Org libVorbis I
>>>>>(84.b+117) string >00000000
>>>>>>(84.b+117) string <20020717 (pre-1.0 CVS)
>>>>>>(84.b+117) string 20020717 (1.0)
>>>>>>(84.b+117) string 20030909 (1.0.1)
>>>>>>(84.b+117) string 20040629 (1.1.0 RC1)
>>>>>>(84.b+117) string 20050304 (1.1.2)
>>>>>>(84.b+117) string 20070622 (1.2.0)
>>>>>>(84.b+117) string 20090624 (1.2.2)
>>>>>>(84.b+117) string 20090709 (1.2.3)
>>>>>>(84.b+117) string 20100325 (1.3.1)
>>>>>>(84.b+117) string 20101101 (1.3.2)
>>>>>>(84.b+117) string 20120203 (1.3.3)
>>>>>>(84.b+117) string 20140122 (1.3.4)
>>>>>>(84.b+117) string 20150105 (1.3.5)
# non-Vorbis content: Opus https://tools.ietf.org/html/rfc7845#section-5
>>28 string OpusHead \b, Opus audio,
!:mime audio/ogg
>>>36 ubyte >0x0F UNKNOWN VERSION %u,
>>>36 ubyte&0x0F !0 version 0.%u,
>>>>46 ubyte >1
>>>>>46 ubyte !255 unknown channel mapping family %u,
>>>>>37 ubyte x %u channels
>>>>46 ubyte 0
>>>>>37 ubyte 1 mono
>>>>>37 ubyte 2 stereo
>>>>46 ubyte 1
>>>>>37 ubyte 1 mono
>>>>>37 ubyte 2 stereo
>>>>>37 ubyte 3 linear surround
>>>>>37 ubyte 4 quadraphonic
>>>>>37 ubyte 5 5.0 surround
>>>>>37 ubyte 6 5.1 surround
>>>>>37 ubyte 7 6.1 surround
>>>>>37 ubyte 8 7.1 surround
>>>>40 lelong !0 \b, %u Hz (Input Sample Rate)