#	$OpenBSD: dolby,v 1.1 2004/06/03 03:14:19 tedu Exp $

# ATSC A/53 aka AC-3 aka Dolby Digital <ashitaka@gmx.at>
# from http://www.atsc.org/standards/a_52a.pdf
# corrections, additions, etc. are always welcome!
#
# syncword
0       beshort         0x0b77  ATSC A/52 aka AC-3 aka Dolby Digital stream,
# fscod
>4      byte&0xc0       0x00    48 kHz,
>4      byte&0xc0       0x40    44.1 kHz,
>4      byte&0xc0       0x80    32 kHz,
# is this one used for 96 kHz?
>4      byte&0xc0       0xc0    reserved frequency,
#
>5	byte&7 = 0		\b, complete main (CM)
>5	byte&7 = 1		\b, music and effects (ME)
>5	byte&7 = 2		\b, visually impaired (VI)
>5	byte&7 = 3		\b, hearing impaired (HI)
>5	byte&7 = 4		\b, dialogue (D)
>5	byte&7 = 5		\b, commentary (C)
>5	byte&7 = 6		\b, emergency (E)
# acmod
>6      byte&0xe0       0x00    1+1 front,
>6      byte&0xe0       0x20    1 front/0 rear,
>6      byte&0xe0       0x40    2 front/0 rear,
>6      byte&0xe0       0x60    3 front/0 rear,
>6      byte&0xe0       0x80    2 front/1 rear,
>6      byte&0xe0       0xa0    3 front/1 rear,
>6      byte&0xe0       0xc0    2 front/2 rear,
>6      byte&0xe0       0xe0    3 front/2 rear,
# lfeon (these may be incorrect)
>7      byte&0x40       0x00    LFE off,
>7      byte&0x40       0x40    LFE on,
#
>4	byte&0x3e = 0x00	\b, 32 kbit/s
>4	byte&0x3e = 0x02        \b, 40 kbit/s
>4	byte&0x3e = 0x04        \b, 48 kbit/s
>4	byte&0x3e = 0x06        \b, 56 kbit/s
>4	byte&0x3e = 0x08        \b, 64 kbit/s
>4	byte&0x3e = 0x0a        \b, 80 kbit/s
>4	byte&0x3e = 0x0c        \b, 96 kbit/s
>4	byte&0x3e = 0x0e        \b, 112 kbit/s
>4	byte&0x3e = 0x10        \b, 128 kbit/s
>4	byte&0x3e = 0x12        \b, 160 kbit/s
>4	byte&0x3e = 0x14        \b, 192 kbit/s
>4	byte&0x3e = 0x16        \b, 224 kbit/s
>4	byte&0x3e = 0x18        \b, 256 kbit/s
>4	byte&0x3e = 0x1a        \b, 320 kbit/s
>4	byte&0x3e = 0x1c        \b, 384 kbit/s
>4	byte&0x3e = 0x1e        \b, 448 kbit/s
>4	byte&0x3e = 0x20        \b, 512 kbit/s
>4	byte&0x3e = 0x22        \b, 576 kbit/s
>4	byte&0x3e = 0x24        \b, 640 kbit/s
# dsurmod (these may be incorrect)
>6      beshort&0x0180  0x0000  Dolby Surround not indicated
>6      beshort&0x0180  0x0080  not Dolby Surround encoded
>6      beshort&0x0180  0x0100  Dolby Surround encoded
>6      beshort&0x0180  0x0180  reserved Dolby Surround mode