#8 DVD-Audio/DVD-A 16/20/24 bit support
DVD-Audio (16/20/24 bit) playback/decoder support:
General request for full "DVD-Audio" support on behalf of
all your users ;-) (Note! "DVD-Audio" is aka: "DVD-A").
LPCM != PCM, so should not be that hard to code, or?
PPCM != PCM, too (don't know)?
VideoLAN VLC plays them but don't think MPlayer do yet?
http://mplayerhq.hu/pipermail/mplayer-dev-eng/2004-
October/thread.html#30054
More on the "DVD-Audio" standard ("DVD-A"):
Short description: DVD-A standard as decived by "The
Working Group (WG-4)" supports up to six channel
surround sound, and yes it is designed for music, not
video. The surround sound on standard DVD-Video's is in
a compressed format: either Dolby Digital or DTS. These
are both 'lossy' forms of compression in which some of
the musical signal (thought to be inaudible, however
audiophiles disagree) is dispensed with in order to realise
huge space savings; but DVD-A use a different encoding
technique for its high quality sound: DVD-A used MLP
(Meridian Lossless Packing) which is sometimes also
refered to as PPCM. Note that almost all DVD-A discs are
also released with standard DVD-Video content as well
so they'll work in regular DVD players, this content is a
straight copy of the main DVD-A program (which,
remember, usually only has sound and still pictures), the
DVD-Video portion usually has its sound recorded in
Dolby Digital or DTS 5.1, this makes most DVD-A discs
and be played on standard DVDs with lower audio
quality, although still in surround sound (as a standard
DVD-player will only play the duplicate AC3 or DTS
tracks that is also on the disk, and not the full quality
PCM tracks).
MLP Meridian Lossless Packing; the digital encoding
technique used for DVD Audio. This is based on the PCM
system used for CDs, but uses a higher sampling
frequency (typically 88.2kHz or 96kHz for six channel
signals and up to 192kHz for stereo signals, compared
with CDs 44.1kHz) and greater resolution (up to 24 bits,
compared with CDs 16, yielding 256 times CDs
resolution). It also employs a special compression
technique developed by the British company Meridian
which, unlike Dolby Digital and DTS, preserves the
original signal perfectly.
PCM Pulse Code Modulation, the oldest and most
commonly employed digital encoding technique. A sample
of the analogue signal is taken many thousands of times
each second, and its level is mapped onto a digital
number.
PPCM Packed Pulse Code Modulation, another term for
MLP.
PS! Not directly related indirectly FYI know this:
A few DVDA are protected by The Verance Watermark
Secure Digital Music Initiative (SDMI), SDMI hack:
http://cryptome.org/sdmi-attack.htm
http://www.nanocrew.net/software/SDMI/
Logged In: NO
Free open sourced DVD-Audio Tools + samples available:
http://dvd-audio.sourceforge.net/
PS! Check out DVDA - The DVD Association: www.dvda.org