Just curious.
Per this linked MSNBC article it sounds powerful but there are no technical details as to how the anti-copy mechanism works and I’m not sure how a CD would, or could know if it was being copied once, twice or a million times. Anyone have more complete info as to how this technology is being implemented?
The article I read said that the scheme introduces random noise at regular intervals. The noise is of such short duration that the error-correcting software built into audio CD players could handle it with out you hearing it. A CD-ROM drive, however, would read it cold, adding the imperfections into any .wma or .mp3 file you create from the CD, making them worthless.
Syzygy’s explanation is backed up by this article:
http://www.newscientist.com/news/news.jsp?id=ns9999998
But it also says “Macrovision is reluctant to discuss how SafeAudio works.”
This isn’t consistent with what I’ve heard about the CDs… everything I’ve read says that they won’t play at all in a CD-ROM drive, and in fact that’s why this woman is suing over them.
OTOH, this may be an entirely different system from Universal’s.
That explanation seems quite poor and doesn’t make much sense. If the boomboox can do it, so can the computer. I cannot see why not.
Other protection schemes rely on requiring the reader (drive) to participate in the scheme. This would work but it means you could not read the CD with old equipment.
We are talking digital extraction because you can always just copy from the analog signal.
Also, from what I understand of how CDs work, the same error correction is used whether reading the CD to play it or to digitally extract it. Audio sectors don’t have error correction checksums like data sectors do (which saves a lot of space, letting you fit 74 minutes of audio - 740MB - on a disc that only holds 650MB of data).
Hmm, I wonder what audio CDR’s will do, after all I am paying royalties to be able to copy discs.
Don’t know if you were being sarcastic or not, but so-called ‘audio CDRs’ are absolutely no different physically from any other CDRs. Other than, like you said, costing more for the royalties.
And I predict this will be cracked within about…3 weeks after the CDs become widely distributed.
I dont have technical information, but what people have said is pretty much the same way I have heard that its done. At least as far as game CDs go, the company will put “faults” on the CD (irregualar code) that when playing(or installing) the game, the game knows not to pay any attention to those bad spots. But when your burner see’s the bad spots the software assumes a fault on the cd and stops the burn. On the other hand, along the lines of what Anthracite said, there will be a “fix” soon after this is released. There are allready programs you can get (cloneCD is the one I use) that will copy a CD “faults” and all.
dead0man
i have a feeling the added noise may affect sound quality even on a normal CD player. may be subtle but it will more than likely be a bad thing.
There’s a story here with a little more info:
It’s a fluffy news piece, so no more technical detail than the other link I posted, but it does have more information on the companies involved as well as a brief discussion of cracks.
Does anybody know of any bands with protected cd’s that don’t suck (e.g. I know Michael Jackson’s new CD will be protected, but…)? I really want to give cracking 'em a shot.
Some cd copy programs stop on error but others you can tell them to keep copying.
I know that, but if I am paying royalties I am legally entitled to make copies. I hope that the Audio CDR’s just copy the disc – warts and all – without trying to decode things.
I guess, if they get the errors just right, then the interpolation will be the exact same value as the original data and be inaudible. But, do all CD players have the same interpolation algorithm?
There used to be a CD player (Harmon Kardon?) that had an LED to indicate that the ECC was operating and another LED to indicate that interpolation was operating. The idea being that if the ECC signal flashed occasionally, no big deal. If the Interpolation light flashed the CD was hosed.
Aren’t these CD’s going to be pretty susceptible to scratches without ECC?
There’s nothing to prevent you from running a connector cord from your CD player into the ‘Line In’ on your computer and recording that way. This ‘protection scheme’ is just going to piss off people who play audio CDs in their CD-ROM drives.
Not true. There’s something (and I’ve never gotten a clear answer as to what) different, as my stand-alone Stereo CD burner (like this one) detects if the CD is an Audio CD and won’t work if it’s not.
So, whether it’s a formatting issue, a media issue ,or what, something’s different or the burner wouldn’t be able to detect the difference.
Fenris
The stand alone audio CD burners do that to seperate you from your money. There is no quality or formatting difference on audio CDRs except junk they add to force you to buy them.
My point exactly, mblackwell, I have paid for the right to make copies and now they are taking that away from me.
AFAIK, Fenris, the CD’s have a hard-coded serial number or ID of somekind that the Audio CDR’s look for. If you put in a “data” recordable CD it will refuse to burn it.