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Macrovision CD Protection Bypassed

Posted by timothy on from the as-if-it-wouldn't-be dept.

LoPan writes: "The defective CDs that have recently arrived on the market have already had their copy protection broken according to The Register. What I'd like to know is if the discs do not conform to the Red Book standard, and if so, can they actually be sold as audio CD's, with the logo? Are they marked, warning consumers that they're buying a defective product?" The cdfreaks article referenced by the Register article tells you all you need to know. It's Windows-centric, but give it a few weeks and I bet cross-platform answers will show up.

3 of 301 comments (clear)

  1. Re:Question about the DMCA by _xeno_ · · Score: 4, Informative
    How does one define a copyright protecting system?

    Well, they'll have to decide exactly what it means, but the DMCA itself (from the EFF) says in Section 1201, subsection (a)(3):

    `(3) As used in this subsection--
    `(A) to `circumvent a technological measure' means to descramble a scrambled work, to decrypt an encrypted work, or otherwise to avoid, bypass, remove, deactivate, or impair a technological measure, without the authority of the copyright owner; and

    `(B) a technological measure `effectively controls access to a work' if the measure, in the ordinary course of its operation, requires the application of information, or a process or a treatment, with the authority of the copyright owner, to gain access to the work.

    You'll notice that even "impairing" a technical measure is illegal - if you do anything to "avoid" the measure, that is still illegal. It would seem to me that this device would fall under this terms, as it "impares" or "avoids" the measure designed to protect copyright...

    As for whether or not what Macrovision is doing is a "measure" to protect copyright, it would seem that it is, as a "process or treatment" (namely error correction) is required to "access" the work. Which means that most likely, those of us in the United States, the land of the Free*, cannot legally use this system.

    * Does not include tax, title or license. Some restrictions may apply.

    --
    You are in a maze of twisty little relative jumps, all alike.
  2. Mode 1 sectors vs. Red Book sectors by yerricde · · Score: 4, Informative

    when you read in raw mode, you also get the correction data. So it's a simple matter of taking the data you got and correcting it in software

    CD-ROM stores 75 sectors per second. Red Book sectors contain 2,352 bytes, or (44100 samples/chn/sec) * (2 channels) * (2 bytes/sample) / (75 sectors/sec). CD-ROM sectors recorded in mode 1 (the vast majority of computer CD-ROMs) contain 2048 bytes of data and about 300 bytes of error correction data. For more information, read http://www.eaglevisiontv.com/General_Information/C DROM_Formats/body_cdrom_formats.html.

    --
    Will I retire or break 10K?
  3. What about CD players with digital output? by Karpe · · Score: 4, Informative

    It is very common now to buy CD players with digital outputs. How does this anti-copying mechanisms work with these outputs? Isn't it just the case to connect these outputs to a soundcard with a digital input? I know the SB Live! has such a connector, altough it "upsamples" every input to 48kHZ PCM. I know the Santa Cruz by Turtle Beach also has such an input, but am not sure if it also does this "upsample". Well, you wouldn' lose quality by transforming the 44.1 to 48 sampling rate, but if you would then downsample the 48 back to 44.1 I don't know what the algorithms would do. Would they just take the original 44.1k samples or get some of the "generated" samples?