#------------------------------------------------------------------------------
# audio:  file(1) magic for sound formats (see also "iff")
#
# Jan Nicolai Langfeldt (janl@ifi.uio.no), Dan Quinlan (quinlan@yggdrasil.com),
# and others
#

# Sun/NeXT audio data
0	string		.snd		Sun/NeXT audio data:
>12	belong		1		8-bit ISDN u-law,
>12	belong		2		8-bit linear PCM [REF-PCM],
>12	belong		3		16-bit linear PCM,
>12	belong		4		24-bit linear PCM,
>12	belong		5		32-bit linear PCM,
>12	belong		6		32-bit IEEE floating point,
>12	belong		7		64-bit IEEE floating point,
>12	belong		23		8-bit ISDN u-law compressed (CCITT G.721 ADPCM voice data encoding),
>12	belong		24		compressed (8-bit G.722 ADPCM)
>12	belong		25		compressed (3-bit G.723 ADPCM),
>12	belong		26		compressed (5-bit G.723 ADPCM),
>12	belong		27		8-bit A-law,
>20	belong		1		mono,
>20	belong		2		stereo,
>20	belong		4		quad,
>16	belong		>0		%d Hz

# DEC systems (e.g. DECstation 5000) use a variant of the Sun/NeXT format
# that uses little-endian encoding and has a different magic number
0	lelong		0x0064732E	DEC audio data:
>12	lelong		1		8-bit ISDN u-law,
>12	lelong		2		8-bit linear PCM [REF-PCM],
>12	lelong		3		16-bit linear PCM,
>12	lelong		4		24-bit linear PCM,
>12	lelong		5		32-bit linear PCM,
>12	lelong		6		32-bit IEEE floating point,
>12	lelong		7		64-bit IEEE floating point,
>12	lelong		23		8-bit ISDN u-law compressed (CCITT G.721 ADPCM voice data encoding),
>20	lelong		1		mono,
>20	lelong		2		stereo,
>20	lelong		4		quad,
>16	lelong		>0		%d Hz

# Creative Labs AUDIO stuff
0	string	MThd			Standard MIDI data
>9 	byte	>0			(format %d)
>11	byte	>1			using %d channels
0	string	CTMF			Creative Music (CMF) data
0	string	SBI			SoundBlaster instrument data
0	string	Creative\ Voice\ File	Creative Labs voice data
# is this next line right?  it came this way...
>19	byte	0x1A
>23	byte	>0			- version %d
>22	byte	>0			\b.%d

# first entry is also the string "NTRK"
0	belong		0x4e54524b	MultiTrack sound data
>4	belong		x		- version %ld

# Microsoft WAVE format (*.wav)
0	string		RIFF		Microsoft RIFF
>8	string		WAVE		\b, WAVE audio data
>>34	leshort		>0		\b, %d bit
>>22	leshort		=1		\b, mono
>>22	leshort		=2		\b, stereo
>>22	leshort		>2		\b, %d channels
>>24	lelong		>0		%d Hz
# AVI == Audio Video Interleave
>8	string		AVI\		\b, AVI data

# Extended MOD format (*.emd) (Greg Roelofs, newt@uchicago.edu); NOT TESTED
# [based on posting 940824 by "Dirk/Elastik", husberg@lehtori.cc.tut.fi]
0	string		EMOD		Extended MOD sound data,
>4	byte&0xf0	x		version %d
>4	byte&0x0f	x		\b.%d,
>45	byte		x		%d instruments
>83	byte		0		(module)
>83	byte		1		(song)

# Real Audio (Magic .ra\0375)
0	belong		0x2e7261fd	realaudio sound file

# MTM/669/FAR/S3M/ULT/XM format checking [Aaron Eppert, aeppert@dialin.ind.net]
# Oct 31, 1995
#0	string		MTM		MultiTracker Module sound file
#0	string		if		Composer 669 Module sound data
#0	string		FAR		Module sound data
#0	string		MAS_U		ULT(imate) Module sound data
#0x2c	string		SCRM		ScreamTracker III Module sound data
#0	string		Extended Module	Extended Module sound data

#------------------------
# MPEG:  file(1) magic for MPEG audio.
#
# From <ckane@best.com>
# Show MPEG level, layer, kbit/s, hz, stereo/mono for an MPG audio file.
# This section is lengthy because the kbit/s rate depends on the
# level and layer, and file(1) doesn't allow math on the values.
#

####### MPEG begins with three hex 'f' nibbles.
0	beshort&0xfff0	0xfff0		MPEG
####### Level 2
>1	byte&0x08	0x00		2.0
>>1	byte&0x06	0x00		Layer Unknown,
####### Level 2, Layers I, II, and III
>>1	byte&0x06	0x02		Layer III,
>>>2	byte&0xf0	0x00		0 kbit/s,
>>>2	byte&0xf0	0x10		8 kbit/s,
>>>2	byte&0xf0	0x20		16 kbit/s,
>>>2	byte&0xf0	0x30		24 kbit/s,
>>>2	byte&0xf0	0x40		32 kbit/s,
>>>2	byte&0xf0	0x50		40 kbit/s,
>>>2	byte&0xf0	0x60		48 kbit/s,
>>>2	byte&0xf0	0x70		56 kbit/s,
>>>2	byte&0xf0	0x80		64 kbit/s,
>>>2	byte&0xf0	0x90		80 kbit/s,
>>>2	byte&0xf0	0xa0		96 kbit/s,
>>>2	byte&0xf0	0xb0		112 kbit/s,
>>>2	byte&0xf0	0xc0		128 kbit/s,
>>>2	byte&0xf0	0xd0		144 kbit/s,
>>>2	byte&0xf0	0xe0		160 kbit/s,
>>>2	byte&0xf0	0xf0		? kbit/s,
>>1	byte&0x06	0x04		Layer II,
>>>2	byte&0xf0	0x00		0 kbit/s,
>>>2	byte&0xf0	0x10		8 kbit/s,
>>>2	byte&0xf0	0x20		16 kbit/s,
>>>2	byte&0xf0	0x30		24 kbit/s,
>>>2	byte&0xf0	0x40		32 kbit/s,
>>>2	byte&0xf0	0x50		40 kbit/s,
>>>2	byte&0xf0	0x60		48 kbit/s,
>>>2	byte&0xf0	0x70		56 kbit/s,
>>>2	byte&0xf0	0x80		64 kbit/s,
>>>2	byte&0xf0	0x90		80 kbit/s,
>>>2	byte&0xf0	0xa0		96 kbit/s,
>>>2	byte&0xf0	0xb0		112 kbit/s,
>>>2	byte&0xf0	0xc0		128 kbit/s,
>>>2	byte&0xf0	0xd0		144 kbit/s,
>>>2	byte&0xf0	0xe0		160 kbit/s,
>>>2	byte&0xf0	0xf0		? kbit/s,
>>1	byte&0x06	0x06		Layer I,
>>>2	byte&0xf0	0x00		0 kbit/s,
>>>2	byte&0xf0	0x10		32 kbit/s,
>>>2	byte&0xf0	0x20		48 kbit/s,
>>>2	byte&0xf0	0x30		56 kbit/s,
>>>2	byte&0xf0	0x40		64 kbit/s,
>>>2	byte&0xf0	0x50		80 kbit/s,
>>>2	byte&0xf0	0x60		96 kbit/s,
>>>2	byte&0xf0	0x70		112 kbit/s,
>>>2	byte&0xf0	0x80		128 kbit/s,
>>>2	byte&0xf0	0x90		144 kbit/s,
>>>2	byte&0xf0	0xa0		160 kbit/s,
>>>2	byte&0xf0	0xb0		176 kbit/s,
>>>2	byte&0xf0	0xc0		192 kbit/s,
>>>2	byte&0xf0	0xd0		224 kbit/s,
>>>2	byte&0xf0	0xe0		256 kbit/s,
>>>2	byte&0xf0	0xf0		? kbit/s,
####### Level 2, Hz
>>2	byte&0x0c	0x00		22050 Hz
>>2	byte&0x0c	0x04		24000 Hz
>>2	byte&0x0c	0x08		16000 Hz
>>2	byte&0x0c	0x0c		? Hz
####### Level 1 decoding
>1	byte&0x08	0x08		1.0
>>1	byte&0x06	0x00		Layer Unknown.
####### Level 1, Layers I, II, and III
>>1	byte&0x06	0x02		Layer III,
>>>2	byte&0xf0	0x00		0 kbit/s,
>>>2	byte&0xf0	0x10		32 kbit/s,
>>>2	byte&0xf0	0x20		40 kbit/s,
>>>2	byte&0xf0	0x30		48 kbit/s,
>>>2	byte&0xf0	0x40		56 kbit/s,
>>>2	byte&0xf0	0x50		64 kbit/s,
>>>2	byte&0xf0	0x60		80 kbit/s,
>>>2	byte&0xf0	0x70		96 kbit/s,
>>>2	byte&0xf0	0x80		112 kbit/s,
>>>2	byte&0xf0	0x90		128 kbit/s,
>>>2	byte&0xf0	0xa0		160 kbit/s,
>>>2	byte&0xf0	0xb0		192 kbit/s,
>>>2	byte&0xf0	0xc0		224 kbit/s,
>>>2	byte&0xf0	0xd0		256 kbit/s,
>>>2	byte&0xf0	0xe0		320 kbit/s,
>>>2	byte&0xf0	0xf0		? kbit/s,
>>1	byte&0x06	0x04		Layer II,
>>>2	byte&0xf0	0x00		0 kbit/s,
>>>2	byte&0xf0	0x10		32 kbit/s,
>>>2	byte&0xf0	0x20		48 kbit/s,
>>>2	byte&0xf0	0x30		56 kbit/s,
>>>2	byte&0xf0	0x40		64 kbit/s,
>>>2	byte&0xf0	0x50		80 kbit/s,
>>>2	byte&0xf0	0x60		96 kbit/s,
>>>2	byte&0xf0	0x70		112 kbit/s,
>>>2	byte&0xf0	0x80		128 kbit/s,
>>>2	byte&0xf0	0x90		160 kbit/s,
>>>2	byte&0xf0	0xa0		192 kbit/s,
>>>2	byte&0xf0	0xb0		224 kbit/s,
>>>2	byte&0xf0	0xc0		256 kbit/s,
>>>2	byte&0xf0	0xd0		320 kbit/s,
>>>2	byte&0xf0	0xe0		384 kbit/s,
>>>2	byte&0xf0	0xf0		? kbit/s,
>>1	byte&0x06	0x06		Layer I,
>>>2	byte&0xf0	0x00		0 kbit/s,
>>>2	byte&0xf0	0x10		32 kbit/s,
>>>2	byte&0xf0	0x20		64 kbit/s,
>>>2	byte&0xf0	0x30		96 kbit/s,
>>>2	byte&0xf0	0x40		128 kbit/s,
>>>2	byte&0xf0	0x50		160 kbit/s,
>>>2	byte&0xf0	0x60		192 kbit/s,
>>>2	byte&0xf0	0x70		224 kbit/s,
>>>2	byte&0xf0	0x80		256 kbit/s,
>>>2	byte&0xf0	0x90		288 kbit/s,
>>>2	byte&0xf0	0xa0		320 kbit/s,
>>>2	byte&0xf0	0xb0		352 kbit/s,
>>>2	byte&0xf0	0xc0		384 kbit/s,
>>>2	byte&0xf0	0xd0		416 kbit/s,
>>>2	byte&0xf0	0xe0		448 kbit/s,
>>>2	byte&0xf0	0xf0		? kbit/s,
####### Level 2, Hz
>>2	byte&0x0c	0x00		44100 Hz
>>2	byte&0x0c	0x04		48000 Hz
>>2	byte&0x0c	0x08		32000 Hz
>>2	byte&0x0c	0x0c		? Hz
####### Stereo or Mono
>3	byte&0xc0	0x00		stereo
>3	byte&0xc0	0x40		joint-stereo
>3	byte&0xc0	0x80		dual-channel
>3	byte&0xc0	0xc0		mono