*DVD-Audio

[Edge]

I was wondering if anyone had any info on how to extract data-streams (I imagine AC3, but I'm not sure on even this issue) from *.AOB files contained in the AUDIO_TS directory on DVD-Audio discs. It appears that these files don't suffer from the same issue as files in the VIDEO_TS folder (eg: not CSS encrypted; I copied them off using just Explorer), but I've been unable to find any utilities/tools to work with them.

For the curious, here's the contents of the AUDIO_TS directory of Metallica's DVD-Audio disc--

Volume in drive R is METALLICA_BLACK
Volume Serial Number is 012E-45F4

Directory of R:\AUDIO_TS

03/07/2001 03:06a <DIR> .
03/07/2001 03:06a <DIR> ..
03/07/2001 03:06a 6,144 ATS_01_0.BUP
03/07/2001 03:06a 6,144 ATS_01_0.IFO
03/07/2001 03:06a 1,073,709,056 ATS_01_1.AOB
03/07/2001 03:06a 1,073,709,056 ATS_01_2.AOB
03/07/2001 03:06a 1,073,709,056 ATS_01_3.AOB
03/07/2001 03:06a 1,073,709,056 ATS_01_4.AOB
03/07/2001 03:06a 1,073,709,056 ATS_01_5.AOB
03/07/2001 03:06a 287,111,168 ATS_01_6.AOB
03/07/2001 03:06a 131,072 AUDIO_PP.IFO
03/07/2001 03:06a 4,096 AUDIO_SV.BUP
03/07/2001 03:06a 4,096 AUDIO_SV.IFO
03/07/2001 03:06a 8,130,560 AUDIO_SV.VOB
03/07/2001 03:06a 10,240 AUDIO_TS.BUP
03/07/2001 03:06a 10,240 AUDIO_TS.IFO
03/07/2001 03:06a 1,327,104 AUDIO_TS.VOB
03/07/2001 03:06a 3,145,728 DVDAUDIO.BUP
03/07/2001 03:06a 3,145,728 DVDAUDIO.MKB
17 File(s) 5,671,577,600 bytes
2 Dir(s) 0 bytes free

Again, I'm guessing the audio content is in all of the AOB files, I'm not sure what the MKB file is (that's a new one), but it has the same exact size as the BUP above it (and it has the exact same content according to "FC /b" at the command prompt).

Any help would be appreciated though, thanks! =)

[DSPguru]

as far as i remember, DVD-Audio holds music compressed in MLP format. that's not AC3...

MLP is a loseless compression, AC3 is lossy.
they are both multichannel, but MLP also support 24bits/96khz and other superior-sound-quality coding.

[Doom9]

hmm.. you can copy these? but I bet they're still encrypted. DVD Audio uses an encryption format superior to CSS (or so they say.. until it gets cracked ;)

[Edge]

Originally posted by Doom9
hmm.. you can copy these? but I bet they're still encrypted. DVD Audio uses an encryption format superior to CSS (or so they say.. until it gets cracked ;)
Yah, it just copied right off. Case in point--


Microsoft Windows 2000 [Version 5.00.2195]
(C) Copyright 1985-2000 Microsoft Corp.

C:\Documents and Settings\Administrator>r:

R:\>cd AUDIO_TS

R:\AUDIO_TS>f:

F:\>mkdir "DVD-Audio Test"

F:\>cd "DVD-Audio Test"

F:\DVD-Audio Test>copy r:*.*
r:ATS_01_0.BUP
r:ATS_01_0.IFO
r:ATS_01_1.AOB
r:ATS_01_2.AOB
r:ATS_01_3.AOB
r:ATS_01_4.AOB
r:ATS_01_5.AOB
r:ATS_01_6.AOB
r:AUDIO_PP.IFO
r:AUDIO_SV.BUP
r:AUDIO_SV.IFO
r:AUDIO_SV.VOB
r:AUDIO_TS.BUP
r:AUDIO_TS.IFO
r:AUDIO_TS.VOB
r:DVDAUDIO.BUP
r:DVDAUDIO.MKB
17 file(s) copied.

F:\DVD-Audio Test>
I also did an "FC /b" (file compare) on all of the copied off files in case the data that got written to disk was different than the data off of the DVD and AFAIK it appears the same. It could still be encrypted like you said (I haven't heard of any PC DVD-Audio players as of yet), but I'm definately curious if it's at all possible nonetheless. =) And like you said, even if it is, it's only a matter of time. Incidentally, some of the files in the VIDEO_TS directory are CSS encrypted, so clearly they're using the tools they have available. (The video content is tiny in comparison though, just the bare minimum to play the music and have a few menus-- you'd think bands/musicians would want to utililize the format to its logical ends; music videos for all the tracks and so on.)

If anyone has any ideas or knows of any tools that would possibly help with this, drop me a line (**OR** if anyone even knows of any PC DVD-Audio disc players-- It seems nothing like this exists currently). Thanks. =)

[ChristianHJW]

If i remember correctly the MLP is only used for 6 channel 24 Bit 96 KHz surround sound on DVD-Audios.

Stereo is 24 Bits 192 KHz pure PCM, no compression ....

[mpucoder]

The fact that you can copy and verify the files doesn't mean they're not encrypted, just that you don't need to "authenticate" the drive. CPPM, which is used for DVD-Audio, is really nasty. The .mkb file is a "media key block" which indicates CPPM is being used (not surprising considering Metallica's stand against Napster)

edit: Audio formats allowed -
LPCM (1-6 channels, 44.1K, 48K, 88.2K, 96K, 176.4K, or 192K, 16/20/24 bits) mandatory
MLP (Meridian Lossless Packing) same options as LPCM, players are required to support
also allowed Dolby Digital (required if video accompanies), MPEG 1&2, and DTS.
video may appear in AOB's or VOB's - the difference is in restrictions, VOB is identical to DVD-video, and may be CSS encrypted (but not CPPM). AOB's can use both CPPM and CSS.

How nasty is CPPM? keys are changed every PACK (1920 bytes), keys are recorded in the sector header, which is not readable by DVD-Rom. Ecryption is much stronger than CSS (they learned) with 56-bit keys applied to 64-bit data chunks.

I'm glad I like movies better.

[kheops]

Originally posted by mpucoder

How nasty is CPPM? keys are changed every PACK (1920 bytes), keys are recorded in the sector header, which is not readable by DVD-Rom.

So I suppose that no win32 player exists yet to play these files...
Do you know if someone is studying the "cppm" format to make a decrypter ?
Lightning and the author of smartripper, what do you think ?

thanks.

[mpucoder]

Well, using a DVD-Rom drive you'll have to work without the keys. Have you ever watched how long it takes for SmartRipper to deduce the key? And those are EASY compared to CPPM. But, let's say you can crack each key in about 1 second, that gets you roughly 2K of the 4G disk. Total time would be 2,000,000 seconds, or 23 days, 3 hours, 33 minutes, and 20 seconds.

[kheops]

Originally posted by mpucoder
23 days, 3 hours, 33 minutes, and 20 seconds.
for sure it doesn't take so long in a standalone player :)

your previous post says
much stronger than CSS (they learned) with 56-bit keys applied to 64-bit data chunks

is the decrypting process of a standalone soooo powerful that even 1ghz computers we can easily find now would need so much time to decrypt a dvd audio ?

i feel lost...

[Rhaegar Targaryen]

Originally posted by kheops


is the decrypting process of a standalone soooo powerful that even 1ghz computers we can easily find now would need so much time to decrypt a dvd audio ?

i feel lost...

I dont think you quite understand how these things work. A standalone would not "crack" it using a brute-force method. The standalone maker would have a license from blahblahblah consortium to use some sort of Decryption chip which can read the file.

Only on computers we would need to do brute-force cracking since we don't know the details of the encryption method.

[mpucoder]

That's close, but not exactly true. We do know the details of the encryption method. What a computer using a DVD-Rom reader cannot get is the decryption keys. These are recorded on the disk in an area that no current DVD-Rom can access, making brute force the only means of decrypting.
There are 2 possible futures, and neither will make everybody happy. 1) The legislation that we all oppose forcing copy protection into all removable-media and recordable devices passes, in which case you will see DVD-Audio players for Windows (but it will require a new DVD drive, and possibly new HD as well). 2) You will never see a DVD-Audio player for Windows, Linux, or any other OS.

Personally, I like freedom, and if that means never ripping a DVD-Audio disk, so be it.

[Edge]

Originally posted by mpucoder
That's close, but not exactly true. We do know the details of the encryption method. What a computer using a DVD-Rom reader cannot get is the decryption keys. These are recorded on the disk in an area that no current DVD-Rom can access, making brute force the only means of decrypting.
There are 2 possible futures, and neither will make everybody happy. 1) The legislation that we all oppose forcing copy protection into all removable-media and recordable devices passes, in which case you will see DVD-Audio players for Windows (but it will require a new DVD drive, and possibly new HD as well). 2) You will never see a DVD-Audio player for Windows, Linux, or any other OS.

Personally, I like freedom, and if that means never ripping a DVD-Audio disk, so be it.
I find it hard to believe that it can't be read though.. sure, there's no players in existance for PC's, but then the demand probably doesn't even exist yet. I haven't seen anything that leads me to believe that there's any special unreadable blocks of data that are needed to decode DVD-Audio; the answer to me seems to be that nobody has simply written one yet (again, due to (lack of) demand).

Do you have any concrete evidence that these encoded blocks exist? A website with details on the specification, or perhaps some of your own research? I'm genuinely curious about what type of roadblocks exist, but I'd like some details. =)

[mpucoder]

Yes, the book DVD Demystified, 2nd edition, pp 193-195, 488.

[Edge]

Originally posted by mpucoder
Yes, the book DVD Demystified, 2nd edition, pp 193-195, 488.
Awesome, didn't have that book (or even know it existed)-- good bn.com though, just ordered it, should be here sometime next week. Is there any other material worth reading, be it online or off, that you could suggest?

[mpucoder]

Well, there is Jim Taylor's website DVD Demystified (http://www.dvddemystified.com) which contains the dvdfaq, but that is mostly a tease to get you to buy his book. Also, the book doesn't tell everything, that would put Mr. Taylor in violation of the NDA he must have signed to get his info.
And for DVD-Video stuff that has been gleaned from many sources on the web, may I humbly suggest MPUCoder's DVD Info (http://members.aol.com/mpucoder/DVD/index.html)

[Edge]

I asked the author of DVD Demystified (and the DVD-FAQ) about DVD-Audio on home PC's and this was his response--

DVD-Audio could be played using current DVD-ROM drives, but no one has
released any software to do so.

--
Jim Taylor
Author of DVD Demystified and the DVD FAQ <http://dvddemystified.com>

----

This was in answer to the basic question "Can current DVD-ROMs in PCs play DVD-Audio, or is new firmware and/or hardware required to play such discs - and if so, is there software out now or in development to meet this need?".

Just a follow-up for anyone curious about DVD-Audio and the possibility of ripping it (afterall, if it can be played, it most likely can be ripped).

[michaelvv]

Hello everybody...

Is it possibly to make a copy/backup of a DVD-AUDIO disc
I had heard it isn't possible ???????

Had tried but without any success.....

Sincerely

michael , denmark.

[ultrabrutal]

I have backed up the dvd video part of the disc (Metallica black album). However the dvd audio part is over 6 gb, and as far as I know the encryption has not been broken.
Anyways, since it's over 4.7 you have nowhere to burn it. You can store it on your HD or reencode it, but then you could just rip the ac3 from the dvd video part.

I made a miniDVD from my dvd audio Metallica disc. Works great in my Afreey. I did this before I bought a DVD Audio player. Wow what a difference in sound. DVD Audio kicks CD and DVD Video to hell :)

[machine70]

i just bought a dvd audio player the sound is good but is downsampled if you go through the digital output .
the only way to listen to 96khz 24bit sound is to to go through the analog output so i asked my self is it possible to copy the dvd-audio and to remove all this protections?
thx

[sebus]

I believe that the latest Creative Audigy 2 software includes the player for DVD-Audio.
Software itself was available on fileconnect and later on some sites. File was named sb_install_eng.zip

sebus

[Sven Bent]

I made a miniDVD from my dvd audio Metallica disc. Works great in my Afreey. I did this before I bought a DVD Audio player. Wow what a difference in sound. DVD Audio kicks CD and DVD Video to hell :)

probaly more a mastering thing then an actuall technical thing.
unlees you have som bad cd-player.

there is no REAL reason that dvd audio is supperior then cd audio. only in theory.

the noiselevel of a cd is lower then the nosie in a soundproof studie.
that is that the "resoultiosn" of cd audio can pick up the noise from a soundproof studio.

[Wilbert]

Any news?

DVD-Audio could be played using current DVD-ROM drives, but no one has released any software to do so.

I got my first audio dvd yesterday (the one of the Corrs with AC3 tracks AFAICT). To my surprise I could play them with PowerDVD (using the digital out of my soundcard --> external receiver). Since I heard audio through my six boxes, I guess that AC3 tracks were played.

However when I rendered an AOB file through graphedit it only connected the LPCM tracks (which were also present on the disc).

[Edge]

Originally posted by Sven Bent
there is no REAL reason that dvd audio is supperior then cd audio. only in theory.Pardon? DVDA has a much higher quality potential than CD Audio. It also uses lossless compression (unlike Dolby Digital or DTS) that can encode to extremely high frequencies and at varying bitrates (up to 24-bit). It supports 2 channel to 6 channel audio.

DVD Audio is far superior to CD Audio, and in a few good ways, superior to DVD Video's audio capabilities.

[Edge]

Originally posted by Wilbert
Any news?Well, given that Creative has released software that can supposedly play DVD Audio discs on a PC, I have to assume that any copy protection is either already supported by existing DVD-ROM drives, or the protection is done via software somehow. I'm curious again about the possibilities for backing up DVD Audio discs, and am wondering if there's any new news on work being done towards that end. =)

[puzio]

Hello All.

DVD-AUDIO disk can be played on PC with WinDVD Platinum and InterVideo DVD-AUDIO Pack (39USD).

[Andrey]

>>Pardon? DVDA has a much higher quality potential than CD Audio.
>>It also uses lossless compression (unlike Dolby Digital or DTS)
>>that can encode to extremely high frequencies and at varying
>>bitrates (up to 24-bit). It supports 2 channel to 6 channel audio.

Not so simple. Yes, the dynamic range is better (24 vs 16 bits, count Db by yourself). But when listening to the music, your ear need time to swith, so this is not important. You can simply compress the range, btw.
Yes, the frequences are better, but is is not important also, because, for example I can not hear above 16KHz, my former mysic teacher - above 20KHz. If you feel uncomfortable, you can add a white noise or something above :):)
6 Channels is a plus, of course. But you need recording to be done for 6 channels (not creating them as usual by phase shift from 2) and this is hard to be done.

>>superior to DVD Video's audio capabilities.
BTW, DTS sound for cinema is lossless too... (some sort of PCM).

P.S. Just my 2 cents :)
And about that Metallica disk :)
There are a rumors :), that it is created from regular record...

[SomeJoe]

Originally posted by Andrey
>>superior to DVD Video's audio capabilities.
BTW, DTS sound for cinema is lossless too... (some sort of PCM).

Not true. DTS is lossy, however, the codec uses less psychoacoustic modeling/masking and more ADPCM/prediction when compared to AC3 and MPEG-2 codecs. Listen and be the judge of whether you think that's a good thing or not. ;)

The only lossless audio codec is MLP.

Originally posted by Andrey
And about that Metallica disk :)
There are a rumors :), that it is created from regular record...

Figures. :rolleyes:

[Andrey]

>> Not true. DTS is lossy, however, the...
Ohh... I've had a terrible headache and could be wrong, but as
I remeber, there are two DTS codecs - lossy and lossless (or it is lossy too ? Something about it was at dtsonline.com). One is used in DVD, other is used for theatrical releases.
May be somebody will correct me, if I'm wrong... Sorry.
That was a good celebration :)
Happy New Year to All !!!

[Edge]

Originally posted by Andrey
Not so simple. Yes, the dynamic range is better (24 vs 16 bits, count Db by yourself). But when listening to the music, your ear need time to swith, so this is not important. You can simply compress the range, btw.
Yes, the frequences are better, but is is not important also, because, for example I can not hear above 16KHz, my former mysic teacher - above 20KHz. If you feel uncomfortable, you can add a white noise or something above :):)
I agree that it's not going to be very perceptible, but the issue for me is that it's pretty much a 1:1 copy of the original source material. I've always been annoyed with CD Audio and the various DVD-Video audio formats because they either sacrifice dynamic range (CDA is 44.1 KHz / 16-bit, while most studio sources are 96 KHz / 24-bit or better), or you potentially sacrifice quality (Dolby Digital and DTS are lossy).

6 Channels is a plus, of course. But you need recording to be done for 6 channels (not creating them as usual by phase shift from 2) and this is hard to be done.
6 channel sources are not difficult. Depending on the performance being recorded multiple mics are usually in use, each creating their own high quality source that can be designated for one of the 6 channels. It's a mixing process to be sure, but if you were recording an orchestra you'd likely have many more than 6 sources to play with, and would in fact likely merge some of the sources to create composites for a specific channel.

I think the ideal audio format would allow for hundreds of channels and do the mixing in the consumer device (e.g. - in the A/V Receiver or in the media player that plays the format). Again, going back to an orchestra (like the London Symphony), each "channel" would represent each individual orchestra members instrument, allowing the end user to turn each instrument on or off during playback. Naturally I'm not saying you'd have hundreds of speakers in your living room-- the format would likely also include a "sitting composition" that told the playing device which instruments were to be played by which of the available 6 physical speakers (or however many speakers are available and their position with respect to the listener). End users would also be able to create their own "sitting" compositions that placed the instruments where they wanted them to be. Mixing would be done on the fly, and for the novice the default sitting composition included would be the one they'd listen to (likely the same one used for the audio CD or in the movie if a soundtrack), but for people wanting to customize the experience they would have that option. Such customizations would either be stored on the media (perhaps in a partially re-writable portion of the disc) or in some internal memory of the playing device, or on a portable memory device (similar in form factor to the memory cards used in gaming consoles).

A format such as described above would require a huge medium to store the data on (well, for an orchestra it would anyways, at least if you gave each instrument it's own channel-- for a performance by say, Metallica again, there's less than a dozen possible sources/channels to deal with).. but such a medium would provide the listener with multiple ways to enjoy the music being listened to. (Apologies for the long rant on my dream audio format, heh).

And about that Metallica disk :)
There are a rumors :), that it is created from regular record...
Well, not sure on this, it's entirely possible. I'd think they'd use the original studio sources though, because again, there were likely multiple mics present to record from different perspectives. The audio on the Metallica disk is definitely multi-channel, but I imagine that's more an attribute of the mixing that was done rather than the way the band was positioned during recording. :P But yeah, it's possible about the actual sources that were used that you are correct. =)

[Andrey]

>>but the issue for me is that it's pretty much a 1:1 copy

In this case truth is on your side :)
It can give additional "sharpness/truliness" to the record. Yep. But I'm sure personally I'll not hear a differense :(

BTW, as I understand, additional bits/sample (24) will not improve quality much, but the errors done during ADC-DAC will be lesser.

But as for multichannel audio - I've never seen even stereo recording in my country :) It is mostly recorded at mono and then they add some instruments later with differences in channels. :)
So, about your multichannel format vision - it is far future for me :)
But you know - dreams are supposed to come true :) :P

About that Mettallica disk - yep, I'm NOT telling "it IS NOT recorded in multichanel", but as small Metallica fan, I read some threads about it long ago, where "specialists" doubts it is multichannel record.
But this is only rumors... No proven facts...