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DVD-Audio's CPPM Circumvented
Bodysurf writes "After DVD-Video's CSS encryption was broken in 1999, the music industry chose a much more secure copy-protection method for DVD-Audio called Copy Protection for PreRecorded Media (CPPM). This protection scheme has remained publicly uncracked, but it was circumvented recently, providing the ability to save the unencrypted digital audio data. CDFreaks has the details."
DVD-Audio's CPPM can be got around with a WinDVD patch
.WAV files.
Posted by Seán Byrne on 06 July 2005 - 09:50 - Source: Rarewares
When DVD-Video's encryption had been broken about 6 years back, the next generation of the Audio CD, DVD-Audio had been delayed for several months. It was originally to use the CSS2 encryption scheme, but the breaking of CSS meant the music industry no longer wanted anything to do with CSS in the new upcoming DVD-Audio format at the time. As a result, DVD-Audio took on Content Protection for Pre-recorded Media (CPPM), a much more advanced copy-protection system, which includes Key Blocks and watermarking and allows revocation (for compromised devices).
It was not long ago that DVD-Audio playback software came to the PC. For example Creative's SoundBlaster Audigy 2 comes with a DVD-Audio as well as WinDVD's DVD-Audio add-on. So, rather than try to compromise the DVD-Audio's encryption itself, someone has succeeded in making a patch that uses WinDVD to perform the decryption and playback, but instead pipes the decrypted audio output to the hard drive instead of the sound card. The patch which includes several tools requires WinDVD 5, 6 or 7 to work.
Several tools to work with DVD-Audio (read: ripping)
They require WinDVD 5, 6 or 7 installed, as they don't do the decryption themselves, and instead patch WinDVD to output the decrypted stream to disk instead of the sound card.
The tools are:
* DVD-A ripper: Intended to decrypt CPPM protected AOB and VOB files on DVD-Audio discs.
* PPCM ripper: Intended to capture Packed PCM (MLP) stream (stereo or multichannel) to
* DVD-A Explorer: Intended to peep&grab on DVD-Audio tracks (PCM and Packed PCM).
This tool is available at Rarewares here.
While InterVideo is likely to update its software to block the use of this patch, it appears that DVD-Audio's CPPM has been compromised at least in DVD-Audio discs up until this time or until the keys used in the current versions of WinDVD that this tool works on are revoked in upcoming DVD-Audio disc releases. However, this would also mean that WinDVD users would be forced to update their software to play future DVD-Audio discs.
We deserve our free use. And we will take it by any and all means.
That should read: We deserve our fair use and we will take it back by any and all means.
CDfreaks has nothing to do with this release. The guys from RareWares are the ones taking risks to bring these tools to the community.
http://www.rarewares.org/
http://www.hydrogenaudio.org/forums/index.php?show topic=34368&st=0&p=310943&#entry310943/
Good old coral cache
http://www.cdfreaks.com.nyud.net:8090/news/12061
Considering the site already seems to be slashdotted...
.WAV files.
---
DVD-Audio's CPPM can be got around with a WinDVD patch
Posted by Sean Byrne on 06 July 2005 - 09:50 - Source: Rarewares
When DVD-Video's encryption had been broken about 6 years back, the next generation of the Audio CD, DVD-Audio had been delayed for several months. It was originally to use the CSS2 encryption scheme, but the breaking of CSS meant the music industry no longer wanted anything to do with CSS in the new upcoming DVD-Audio format at the time. As a result, DVD-Audio took on Content Protection for Pre-recorded Media (CPPM), a much more advanced copy-protection system, which includes Key Blocks and watermarking and allows revocation (for compromised devices).
It was not long ago that DVD-Audio playback software came to the PC. For example Creative's SoundBlaster Audigy 2 comes with a DVD-Audio as well as WinDVD's DVD-Audio add-on. So, rather than try to compromise the DVD-Audio's encryption itself, someone has succeeded in making a patch that uses WinDVD to perform the decryption and playback, but instead pipes the decrypted audio output to the hard drive instead of the sound card. The patch which includes several tools requires WinDVD 5, 6 or 7 to work.
Several tools to work with DVD-Audio (read: ripping)
They require WinDVD 5, 6 or 7 installed, as they don't do the decryption themselves, and instead patch WinDVD to output the decrypted stream to disk instead of the sound card.
The tools are:
- DVD-A ripper: Intended to decrypt CPPM protected AOB and VOB files on DVD-Audio discs.
- PPCM ripper: Intended to capture Packed PCM (MLP) stream (stereo or multichannel) to
- DVD-A Explorer: Intended to peep&grab on DVD-Audio tracks (PCM and Packed PCM).
This tool is available at Rarewares here [http://www.rarewares.org/others.html%5D.
While InterVideo is likely to update its software to block the use of this patch, it appears that DVD-Audio's CPPM has been compromised at least in DVD-Audio discs up until this time or until the keys used in the current versions of WinDVD that this tool works on are revoked in upcoming DVD-Audio disc releases. However, this would also mean that WinDVD users would be forced to update their software to play future DVD-Audio discs.
Link to software
"DVD Audio Tools", second from bottom.
He is still around; he only focuses on Apple-related hacks AFAIK.
Now accepting PayPal donations!
It doesn't matter what kind of "copy protection" a disc has, I can always get around it. How? Simple. My sound card supports "What U Hear", so basically, it can record sound streams from your computer (ie, if you're playing a flash movie in your browser, and hit record "What U Hear", the sounds from the flash movie, and any other sounds on your computer will be recorded in the exact quality as you hear it).
So yeah, it's just a waste of money.
So which is it?
Both. It just depends on who you are.
The CD format is hopelessly unprotected, but it's also got a huge installed base. If you want people to change you're going to have to convince them that it's an upgrade: higher bit rate, better sepration, liner notes and titles. Then they can slip in what they really want: copy protection. That's the primary goal; the other features are the spoonful of sugar to make the bitter pill go down.
So both properties (features and copy protection) are the "real" reason. The former are the reason for consumers to upgrade; the latter is why the industry makes the upgrade available.
Try searching for DualDisc. Those are hybrid DVD-A/CDs and they are becomming quite popular.
Good point. Thank-you.
Since this is being tried in both the courts of law and of public opinion it is important to keep the argument sane, salient and factual. We are only wanting to keep that to which we are already entitled by law.
Those who fight against fair use are behaving unethically.
>distribution just to show it can be done
>without the RIAA.
It's called http://cdbaby.com/
Enjoy !
----- In Your Cubicle No One Can Hear You Scream...
What was that saying?
"To view it, we have to decrypt them. If we can decrypt them, we can rip them."
That wise man was Bruce Schneier. Check out his book for a very readable yet detailed overview of crypto...
As usual, too many people lose sight of the goal of encryption. It's not to be "foolproof" where no one can make copies, it's to make it hard enough that the casual music fan decides it's easier just to buy the music than go through the hassle of installing software.
Sometimes it's best to just let stupid people be stupid.
It's not stealing though. The term for what's going on is copyright infringement. AND IT IS NOT THE SAME THING AS THEFT!! How many times must it be said? Copyright violation != theft. They're two different crimes. The RIAA wants people to believe that pirates are directly stealing from them and the artists they supposedly represent. This is a false analogy, and frankly, one that the suits at the record labels would love for people like you to keep propagating.
This sig intentionally left blank...
It's the sample rate, moreso to me than the bits per sample. 44.1KHz's nyqust freq (22.05Khz) is close enough into the range of human hearing that artifacting can easily occur. You need VERY good filtering on A/D inputs to have sounds above say 18KHz still present, and the filter level be inaudible at 22Khz (greather than 60dB of attenuation in about a 1/4 octave, so 240dB of attentuation per octave. That's not a simple filter).
By upping the sample rate to 96Khz, the nyquist frequency is so high (48Khz), that the filter requirements aren't nearly so high, and that any artificats that do creep in do so at frequencies well beyond our hearing.
Even on modest gear, it makes a difference.
And by modest, I'm putting the system price at say $2000 (receiver, dvd player, speakers).
Granted, the D/A stage doesn't need these expensive filters that the recording stage does, but it gives the recorders a lot more lattitude to make GOOD recordings. But mass-market CDs sound like crap. The compress (dynamic compression) the hell out of the audio. A well done recording with a bit of dynamic range sounds so much better than most pop recordings do.
16 bits gets you about 96dB of dynamic range possible. 24 bits gets you 145dB of range. Again, the 16 bit version is on the edge of hearable. The 24 bit version isn't. But 96dB is definitely not bad for most systems.
But that's where the dynamic compression comes in, as most CDs I hear have very little dynamic range, and they push it out far enough close to the max volume that the disc can record to cover up any noise in the playback system at low signal levels.
CD-Audio is adequate, but not capable of really replacing high quality analog. DVD-Audio's rates are (the audiophiles mostly agree that the data-rate is higher than they can distingusih, although they'll probably complain about warmth/veiled highs, etc, their perogative, I guess).
Most modern recordings are aimed at playback on low-grade consumer hardware, both home/mobile. The noise floor in mobile audio is enough that very dynamic recordings tend to become half unintelligible, and half earsplitting. When the same CD, in a quiet room in a house, is wonderful (drums have massive impact, but quite passages are, well, quiet). Unfortunately, this is performed at the recording studio, instead of being performed in the car stereo (compressors can be cheaply implemented in the DSP that's dealing with all the rest of the sound-shaping that low-end gear does).
So, unless the recordings really try to take advantage of the format, we'll have the audio equivalent of ball-park hotdogs served on china with silver and crystal.