BMG Backs Down Over Copy-Protected CD

An anonymous submitter sends in: "As reported by The Register, on the 5th of November, BMG released the UK's first copy-protected CD (more information on Eurorights and Fat Chuck's). It uses Cactus Data Shield by Midbar Tech, which aims to prevent CD to CD or digital CD to Minidisc copying, along with converting to MP3, but may have other bad side effects." The submitter continues: "There were complaints from fans and many took their CDs back or wrote to the record company and record shops. Their hard work seems to have paid off since Virgin Megastores has responded to a complaint from one of their customers and said that BMG has set up a helpline to allow people who bought the corrupt version, to exchange it for a real one. Virgin and HMV will also be bringing in new stock of uncorrupted CDs. The message was originally posted to the Official Natalie Imbruglia Bulletin Board (free registration required) in the "White Lies" and "Lillies vs Cactus" threads, but several threads containing complaints against Cactus Data Shield have been deleted so the email has been mirrored on the Free-sklyarov-uk mailing list. This is very good news, but more work needs to be done. Hopefully with pressure from the public other retailers will follow Virgin's example. Also record companies need to be made clear that selling copy protected CDs, that infringe on the public's rights, is not acceptable. The battle isn't over until no new CDs are shipped in these formats so if you find a CD that is copy-protected then report it on Eurorights for the UK, or Fat Chucks for elsewhere, take it back to the shop, and let them, and the record company know your feelings on the issue."

Comments

Re:Midbars patent application for Cactus Data Shie

[Chris Johnson]

I don't think they can guarantee the same method of interpolation is in use in all CD players. Some might interpolate between surrounding good samples, others might just hold the last good sample until the next good one comes along. You can't guarantee what sort of error correction is in use.

For that reason, the name 'Cactus Data Shield' is very appropriate: when ripped it is full of 'spikes' ruining the music, when perfectly interpolated it may possibly be sample-for-sample identical (assuming the substituted samples are ONLY those where surrounding samples interpolated will return the exact, precise amount- I'm not at all sure this is a safe assumption), but when imperfectly interpolated the _best_ output still has traces of the 'cactus spines'- like stubs :)

On a CD player with inferior interpolation it is probably slightly more sonic degradation than you get from DVD-A watermarking because watermarking is bandlimited to avoid the more sensitive areas of hearing, and this 'residual cactus spikes' effect will reach into the highs and spit out artifacts on steep wave slopes.

I know that in debugging azumith-correction algorithms I could hear high-frequency artifacts of just one sample duration when they were of this nature- a departure from the even slope of a waveform. I would respectfully suggest that the dangers of inadequate error correction are more severe and audible than the CDS guys are ready to admit, and that on many CD players traces of high frequency crackling and grunge will still be audible even after 'interpolation'...

As an indie music maven and audio tool coder I have to say I am just tickled by all this. How nice of the music industry cartel to ruin the quality of their products FOR me, thus making it easier for people in basements and dorm rooms to produce music that's actually better than the cartel makes. A few more years of that and they'll have done serious damage to the former popular opinion that industry music is more professional than unsigned music :)