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DVD Drives Defeat Cactus Data Shield

Posted by michael on from the trees-obscure-view-of-forest dept.

jsepeta sends in a story about Cactus Data Shield, one of the schemes to be used for copy-protecting compact discs. A reporter for TechTV notes that DVD drives see right through the disc corruption that Cactus uses to supposedly prevent those CDs from being ripped.

4 of 381 comments (clear)

  1. Difference between copying and reading? by hughk · · Score: 5, Informative
    Look, I know that there is supposed to be a big difference between the error correction on Audio-CD players and the normal CD-R drive, let alone a DVD drive, but in the end, it is a digital bit stream. Bits can be copied, end of story.

    Another point is that many drives have maingenance modes which allow the host computer to see exactly what is on the disk without correction. This is normally used for testing, but again would be very useful for breaking the DMCA. Just read track w/o correction and aply the correction at software level ignoring the bad bits.

    I guess that a DVD-rom drive is more sensitive to errors on conventional CD's as they have much finer bit resolutions for DVDs so they alreasy have the modified error recovery built in.

    Protection of CDs is pointless and it interferes with customers' own rights and annoys the customer. The original article mentions a class action against Universal about Unplayable CDs.

    --
    See my journal, I write things there
  2. Another way around it: by arbitrary+nickname · · Score: 5, Informative

    As described in a comment on FatChucks

    (Tested it on 'Natalie Imbruglia - White Lillies Island' with a Yamaha 6x4x16x SCSI CDRW drive)

    1) Get IsoBuster (A Win32 app)

    2) Rip the entire disc as raw data. May struggle/take a while. Tell it to ignore any read errors

    3) Open the raw file in CoolEdit (or any decent audio editor) as a 44.1Kz 16-bit stereo sample (with Intel byte ordering)

    4) There you have it! The entire CD as one big sample!

    5) In CoolEdit, you can use 'Edit->AutoCue->Find Phrases and Mark' to split the tracks up automatically

    6) Save 'em out, and convert to MP3/Ogg if neccesssary

  3. The people who wrote this article are idiots. by amitv · · Score: 5, Informative

    They keep saying that they couldn't play the first track. Of course they can't play the first track, that's what contains the filesystem with the CDS player.

    Correct me if I'm wrong (nobody's perfect), but this seems pretty simple to me.

    --
    Can you imagine a MOSIX cluster of these?
  4. Re:Soon to be illegal... by Anonymous Coward · · Score: 5, Informative
    But of course.

    There is an excellent review of CPRM, SSSCA and the coming "Secure PC" on The Register. Here's a short excerpt from this article:

    But the CPRM gambit was an early indication that the entertainment industry was deadly serious about removing the free movement of digital media on what has been, for fifteen years, on open platform. ... In August a draft bill called the Security Systems Standards and Certification Act (SSSCA) was proposed by Senator Hollings (D). It proposed mandatory inclusion of copy-protection schemes for domestic and imported PCs, anything in fact, capable of recording digital media.