Idea of ripping an SACD/DVD-A feasible or not?
Apr 1, 2004 at 10:12 AM Thread Starter Post #1 of 23

pennylane

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Obviously you can't right now. But if you had the right optical drive and the right software, would it be possible? If it's possible, is it inevitable? If it's not, why not?
 
Apr 2, 2004 at 3:09 AM Post #4 of 23
Formula for file size for any format is samples per second * bits per sample * number of channels / 8 (for bytes) * song length in seconds.

So, for SACD, it'd be 2,820,000 * 1 * 2-6 (let's call it 2 for now) / 8 * 360. (Let's say it's a 6 minute song) 253,800,000 KB, or about 254MB.

Anyway, the main problem now is that no drives can read SACD or DVD-A. Also, there's the copy protection that you'd have to bypass, which, of course, is a violation of the DMCA. Naughty, naughty
wink.gif


(-:Stephonovich:)
 
Apr 2, 2004 at 3:52 AM Post #6 of 23
DVD-A uses a different format; if you were discussing that. 192 KHz/24 bit. Using the same formula, with those values plugged in, you get a file 414,720,000 KB, or about 415MB. Or were you talking about ripping SACD to a non-standard WAV (if WAV can even handle those bitrates...), and burning them to a DVD? In that case, nothing except a computer could read them. In the end, you'd be forced to downsample to 44.1/16 to allow CDs to read them, or whatever-sample (dunno if it'd be up or down) to 192/24 for DVD-A.

(-:Stephonovich:)
 
Apr 2, 2004 at 4:40 AM Post #7 of 23
It can be done... it will be common eventually. The only question is when and for how much. The Soundblaster Audigy 2 can handle 24 bit / 192 kHz sound... so
very_evil_smiley.gif
 
Apr 2, 2004 at 4:46 AM Post #8 of 23
Many cards can handle 192/24. That's not the issue. Currently, no drives can read them. The only way I can see is hacking together something involving a standalone player that CAN play the required format, and capturing the data on it's way out. IIRC, SACD and DVD-A players don't have a digital out for this very reason, da? However, if you could get the signal after it goes through the decoder, (they're encrypted, remember) but before it goes through the DAC, that might work. Be a ton of work, though.

Or, of course, wait until computers can read the format, and inevitably, someone will find a way. Illegal, perhaps, but they will find a way.

(-:Stephonovich:)
 
Apr 2, 2004 at 4:13 PM Post #9 of 23
Quote:

Originally posted by Stephonovich
Formula for file size for any format is samples per second * bits per sample * number of channels / 8 (for bytes) * song length in seconds.


I understand the point you're making but this formula is misleading. This will only calculate the number of *audio* bits associated with a format. For example, in the AES stream there are 32 bits associated with every sample even though only 20 of them are dedicated to audio. When the audio is actually stored on the disc there is a lot of redundancy, etc added for error correction.
 
Apr 2, 2004 at 5:47 PM Post #10 of 23
Quote:

Many cards can handle 192/24. That's not the issue. Currently, no drives can read them.


Most computer DVD drives can read DVD-Audio discs and Audigy 2 comes with software to play DVD-Audio, I know, I have it and DVD-Audio discs, and yes it's playing the DVD-A stream, not DD5.1, check out Creative's webpage for more info.

Quote:

IIRC, SACD and DVD-A players don't have a digital out for this very reason, da?


Sony XA-9000ES, Pioneer Elite DV-47ai, 59avi, and the new 45ai, Denon DVD-5900, DVD-9000, and some other high end players like dCS have digital out for SACD and DVD-A in the form of Firewire, Denon-Link, and other proprietary interfaces...it's just still encrypted, you can't rip it.


You can't play/capture *native* DSD (SACD) on computers without a very expensive solution (>$40,000, I believe).

Here is the SACD copy protection system:
(I copied from here)

1. SACD Mark, which hides certain disc parameters in the lead-in area by scrambling the data. Drives need this information before they can start reading the disc. A non-compliant drive will, therefore, not be able to get data from any SACD disc.

2. PSP-PDM, which is an invisible watermark that is very difficult to write on a recordable disc and can only be mastered with SACD licensed equipment. It involves using Pit Signal Processing (PSP), which modulates the width of pits on the disc. PSP-PDM is used for Playback Control and for content access control as it contains part of the descrambling key.

3. Scrambled content, using the SACD synchronous stream cipher, which is optimised to achieve high performance in hardware. It needs a key that is partly hidden in the PSP-PDM on the disc and partly hidden in the player hardware.

4. Descrambling algorithm is available in hardware only. The license contract does not allow the algorithm to be made available in software, which would make it too vulnerable for reverse engineering by PC-hackers.

There can also be an optional Visible Watermark, which is a ‘hologram-like’ image that can optionally be placed on the signal side of an SACD disc, using pit signal processing, but with the pit width modulation synchronised so that a pattern can be written. As in the case of bank notes, this mark can be used to indicate to the consumer that the disc is an official product.


So, #4 would make it really hard for an average consumer to rip an SACD because you have to have a hardware DSD card for descrambling. I think it will be much easier for DVD-A when the time does come, since it's PCM and the Audigy and other 24/192 cards can obviously play that.

You could always get a nice soundcard, record at 24/96 or whatever from analog and then burn a DVD of it. That's the easiest way now. You'd lose a little quality but it would still be excellent.
 
Apr 2, 2004 at 6:38 PM Post #11 of 23
I want to do this as well, but can't understand why/how it can be illegal?

If I buy a peice of media, I have legal rights to make as many backups and copies as I want for my own use...it's rights given to the end-user. I make copies of my CDs, why would a SACD (when technology makes it easier) be different?
 
Apr 2, 2004 at 10:53 PM Post #12 of 23
Quote:

Originally posted by SouthPaW1227
If I buy a peice of media, I have legal rights to make as many backups and copies as I want for my own use...


Uhm, sorry, but no - not anymore. You might still have or have not the right to make private backup copies, depending on your location, but breaking copy protections has been legally forbidden pretty much everywhere in the western world in the recent past... For the content creation industry, who is behind those new laws, this ensures that even if private copies are still allowed, these won't be bit for bit equal copies. But if you don't insist on digital copies, you can still go the analogue way in between - at least for now...

Greetings from Hannover!

Manfred / lini
 
Apr 2, 2004 at 11:14 PM Post #13 of 23
This is crazy, there are people who acctually need to make legit copies. I`ve lost/ scratched soo many cds i wish i could have made copies.
 
Apr 2, 2004 at 11:48 PM Post #14 of 23
Quote:

Originally posted by lini
You might still have or have not the right to make private backup copies, depending on your location, but breaking copy protections has been legally forbidden pretty much everywhere in the western world in the recent past...



A huge problem here is that the Digital Millenium Copyright Act and the Home Recording Act are slightly at odds. The DMCA says that it is illegal to bypass copy protetion schemes while the home recording act permits copies for personal use. I am not sure if the DCMA takes precedence over the HRA due to the fact that it was most recently passed into law.
 
Apr 3, 2004 at 12:27 AM Post #15 of 23
I talked to a german hacker about ripping the new audio formats and he told me that it's a extreme complex task.
That's good news since the succeeding team will get lots of reputation, and reputation is what these guys are living for.
An easy task wouldn't be of any interest for them.
Sooner or later we will see these flawed concepts of controlling us floating down the river.
 

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