Monday, July 25, 2005

A Brief History of DVD Copying (Part 1)

The source code for a program called DeCSS was anonymously posted to the Internet in late October 1999. While it was a very small program, and totally unusable in the form it was presented, it did spell out the trade secret used to encrypt data on movie DVDs. This algorithm supposedly had been obtained by "reverse-engineering" a popular PC DVD player. The purpose of the DeCSS program was to remove the encryption on a DVD so that it could be watched using a free player on the Linux operating system*. At the time no such player existed because the association that controlled the secret DVD decryption algorithm (the DVD CCA) would only license it to companies that paid thousands of dollars a year for a licence -- and the authors of the Linux DVD player not only didn't want to pay, they wanted to publish the source code for the algorithm for everyone to see. This didn't bode well with the industry.

Figure 1: Part of the DeCSS source code

Both the DVD Copy Control Association and the Motion Picture Association (MPAA) tried to stop the spread of the DeCSS source code in the weeks following its release. First they claimed the algorithm was a trade secret. After receiving little success with this argument they changed gears and said the code was a violation of a new American law called the Digital Millennium Copyright Act (DMCA). This act made it illegal to create something which circumvents an access control device, in the case of DVDs, the movie's encryption. As the DMCA was very new, the DVD DeCSS lawsuits would be the first of many to challenge this seemingly unbalanced law. The most famous of the lawsuits made a celebrity of a 16 year old Norwegian named boy named Jon Johansen, who has became synonymous with DeCSS.

The Brief History of DVD Copying (Part 2) is now available...

* It should be pointed out as soon as possible that the encryption used on DVD movies does not prevent them from being copied. Think of it this way.. If I wrote this entire posting in Latin, then you could, even though you don't understand Latin, copy it to your own web site. What you couldn't do however is understand it. So while you can copy an encrypted DVD movie, you wouldn't be able to play it without using a licensed DVD player which could decrypt the movie (translate the Latin back to English in our analogy). The DVD CCA simply didn't like the idea that anyone would be able to create their DVD player (especially one that would bypass region codes, allow you to fast forward through warnings, etc.).


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