#2 ifo_types.h constants

[Peter Creath]

You don't have any constants for the following members of
audio_attr_t:

quantization
sample_frequency

I'm not sure whether the various enums you have in dvd_types.h
match the values used in IFO files (now that I look at
DVDAudioFormat_t closely -- LPCM should be 4), but I'm sure this
information will be useful somewhere in the code.

Most of these are fairly easily discernible from IfoEdit:

DVDAudioQuantization_t:
DVD_AUDIO_QUANT_16BIT = 0,
DVD_AUDIO_QUANT_20BIT = 1,
DVD_AUDIO_QUANT_24BIT = 2,
DVD_AUDIO_QUANT_DRC = 3, // dynamic range control

DVDAudioChannels_t:
DVD_AUDIO_CHANNELS_MONO = 0,
DVD_AUDIO_CHANNELS_STEREO = 1,
DVD_AUDIO_CHANNELS_1 = 0,
DVD_AUDIO_CHANNELS_2 = 1,
DVD_AUDIO_CHANNELS_3 = 2,
DVD_AUDIO_CHANNELS_4 = 3,
DVD_AUDIO_CHANNELS_5 = 4,
DVD_AUDIO_CHANNELS_6 = 5, // (Note: IfoEdit only thinks 6 are
allowed...other specs suggest 8)
DVD_AUDIO_CHANNELS_7 = 6,
DVD_AUDIO_CHANNELS_8 = 7,

DVDAudioSampleFrequency_t:
DVD_AUDIO_SAMPLE_FREQ_48KHZ = 0,

However, since IfoEdit doesn't know the constant for 96 kHz, I had
to do a bit of research (i.e. finding a DVD for sale which had 96
kHz LPCM audio). Not surprisingly, since it's the only other valid
sample frequency, the constant is:

DVD_AUDIO_SAMPLE_FREQ_96KHZ = 1

I confirmed this on Queen's "The Game", published by DTS
Entertainment (UPC 9286-01110-9). They use that constant to
encode their 96/24 LPCM track. (They also use the above
constant for 24-bit.) The first bit of the audio track data is
0x80 0x91. This is the one bit of information I couldn't find
documented in any project or software out there.

[Nobody/Anonymous]

Logged In: NO

This should be moved to patches, shouldn't it?