DeCSS

DeCSS was one of the first free computer programs capable of decrypting content on a commercially produced DVD video disc. Before the release of DeCSS, Linux-based computing systems could not play video DVDs.

DeCSS was developed without a license from the DVD Copy Control Association (CCA), the organization responsible for DVD copy protection—namely, the Content Scramble System (CSS) used by commercial DVD publishers. The release of DeCSS resulted in a Norway criminal trial and subsequent acquittal of one of the authors of DeCSS. The DVD CCA launched numerous lawsuits in the United States in an effort to stop the distribution of the software.

DeCSS was devised by three people, two of whom remain anonymous. It was released on the Internet mailing list LiViD in October 1999. The one known author of the trio is Norwegian programmer Jon Lech Johansen, whose home was raided in 2000 by Norwegian police. Still a teenager at the time, he was put on trial in a Norwegian court for violating Norwegian Criminal Code section 145, and faced a possible jail sentence of two years and large fines, but was acquitted of all charges in early 2003. However, on 5 March 2003, a Norwegian appeals court ruled that Johansen would have to be retried. The court said that arguments filed by the prosecutor and additional evidence merited another trial. On 22 December 2003, the appeals court agreed with the acquittal, and on 5 January 2004, Norway's Økokrim (Economic Crime Unit) decided not to pursue the case further.

The program was first released on 6 October 1999 when Johansen posted an announcement of DeCSS 1.1b, a closed source Windows-only application for DVD ripping, on the livid-dev mailing list. The source code was leaked before the end of the month. The first release of DeCSS was preceded by a few weeks by a program called DoD DVD Speed Ripper from a group called DrinkOrDie, which didn't include source code and which apparently did not work with all DVDs. Drink or Die reportedly disassembled the object code of the Xing DVD player to obtain a player key. The group that wrote DeCSS, including Johansen, came to call themselves Masters of Reverse Engineering and may have obtained information from Drink or Die.

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