audio

UNIX下FILE命令的实现源码

#------------------------------------------------------------------------------
# audio:  file(1) magic for sound formats (see also "iff")
#
# Jan Nicolai Langfeldt ([e-mail]), Dan Quinlan ([e-mail]),
# 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 tracks
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

# Extended MOD format (*.emd) (Greg Roelofs, [e-mail]); NOT TESTED
# [based on posting 940824 by "Dirk/Elastik", [e-mail]]
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
0	string		.RMF		RealMedia file

# MTM/669/FAR/S3M/ULT/XM format checking [Aaron Eppert, [e-mail]]
# 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

# Gravis UltraSound patches
# From <[e-mail]>

0	string		GF1PATCH110\0ID#000002\0	GUS patch
0	string		GF1PATCH100\0ID#000002\0	Old GUS	patch

#
# Taken from loader code from mikmod version 2.14
# by Steve McIntyre ([e-mail])
0	string	JN		extended 669 module data
0	string	MAS_UTrack_V00
>14	string	>/0		ultratracker V1.%.1s module sound data
0	string	UN05		MikMod UNI format module sound data
0	string	Extended\ Module: Fasttracker II module sound data
21	string	!SCREAM!	Screamtracker 2 module sound data
1080	string	M.K.		4-channel Protracker module sound data
1080	string	M!K!		4-channel Protracker module sound data
1080	string	FLT4		4-channel Startracker module sound data
1080	string	4CHN		4-channel Fasttracker module sound data
1080	string	6CHN		6-channel Fasttracker module sound data
1080	string	8CHN		8-channel Fasttracker module sound data
1080	string	CD81		8-channel Oktalyzer module sound data
1080	string	OKTA		8-channel Oktalyzer module sound data
# Not good enough.
#1082	string	CH
#>1080	string	>/0		%.2s-channel Fasttracker "oktalyzer" module sound data
1080	string	16CN		16-channel Taketracker module sound data
1080	string	32CN		32-channel Taketracker module sound data

# TOC sound files -Trevor Johnson <[e-mail]>
#
0       string          TOC             TOC sound file

# sidfiles <[e-mail]>
0	string		SIDPLAY\ INFOFILE	Sidplay info file
0	string		PSID			PlaySID v2.2+ (AMIGA) sidtune
>4	beshort		>0			w/ header v%d,
>14	beshort		=1			single song,
>14	beshort		>1			%d songs,
>16	beshort		>0			default song: %d


# IRCAM <[e-mail]>
0	belong		0x64a30400		IRCAM file (NeXT)
0	belong		0x64a30200		IRCAM file (Sun)
0	belong		0x64a30300		IRCAM file (MIPS little-endian)
0	belong		0x0001a364		IRCAM file

# NIST SPHERE <[e-mail]>
0	string		NIST_1A\n\ \ \ 1024\n	NIST SPHERE file

# Sample Vision <[e-mail]>
0	string		SOUND\ SAMPLE\ DATA\ 	Sample Vision file

# Audio Visual Research <[e-mail]>
0	string		2BIT			Audio Visual Research file

# From Felix von Leitner <[e-mail]>
0	string		OggS	Ogg-Vorbis compressed sound file