--- /dev/null
+# AC-3 aka A/52 aka Dolby Digital <ashitaka@gmx.at>
+# corrections, additions, etc. are always welcome!
+#
+# syncword
+0 beshort 0x0b77 AC-3 aka A/52 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,
+# 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,
+# 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