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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."
We deserve our free use.
And we will take it by any and all means.
RTFA again for the best results.
What was that saying?
"To view it, we have to decrypt them. If we can decrypt them, we can rip them."
The only "secure" media format is a CD laminated between two plates of steel.
Hilary Rosen's speech was about her love of money and her desire to roll around naked in a pile of money.
"For every lock there is a key"
Gotta love fair use!
Visualize Whirled P.'s
Probably nobody uses DVD-Audio. The effort spent cracking the copy protection will be proportional to the popularity of the medium. When the DVD Audio section at your local record store is as large as the CD section, we may see some more time being spent on such things.
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.
> I'm a little surprised--why did it take so long for someone to do this?
because it wasn't until last week that someone actually bought a DVD-Audio disk
Anyhoo, this is good news.
;)
Now I can rip this stuff off to 64K MP3, then convert it over to Real, and finally through to it's final form as a DRM'ed WMA.
Chas - The one, the only.
THANK GOD!!!
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/
I would buy their product immediately.
Cool... would you burn me a copy or throw up a torrent?
The constitutional right to be entertained must remain in force
:)
That's what the Right to Arm Bears is all about
"99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
I know this fight against the Man is so very romantic, but the companies can opt out of this arms race in which the hackers have the advantage. The more and more this encryption breaking is done, the industry will spend less and less money on developing new encryption schemes, and instead spend more and more on buying Senators and Representatives to pass draconian measures to prevent you from legally trying (thinking about how) to break the schemes.
Link to software
"DVD Audio Tools", second from bottom.
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.
You are being somewhat selective in your civic values.
I do not think so. As someone who worked as a Customs Inspector for almost a decade and seized many many hardware and software components under the DMCA, I have a keen understanding of the intention and use of the DMCA. It was implemented with the intention of curbing the flow of violative software and the hardware that enabled use of illegal software. It also enabled businesses to better control their marketing districts.
Preventing consumers from fair use activities was never part of the stated reason for the legislation nor were we ever instructed during our briefings to look for articles that would prevent consumers from manipulating legitimate (legally obtained and distributed) software and hardware.
My background stated, I will also assert that I have no problem putting copyright violators in jail or with the seizure of illegally produced and distributed works. I am not advocating any type of free-for-all. I believe people should be fairly compensated for their efforts.
However, /. dislike: My favorite was the court decision that third-party garage door openers are NOT a violation of the DMCA because Congress never intended the DMCA to limit consumer options. Good ruling but this is why I have become cynical about the current usage of the DMCA. It is no longer being applied to the "bad guys" but instead is being increasingly used by corporations to lock consumers out of their rights and choices.
since my time as an Inspector, I have observe many businesses try to warp the usage of the DMCA to their own ends. And not just the usual targets of
The manipulation of the DMCA in effort to extort more money out of the consumer or monopolistically control the consumer is unacceptable and unethical.
I stand by my previous statement.