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DeCSS

DeCSS is a program for descrambling the encryption on DVDs.

The MPAA is trying to make the source code for this program illegal.

But the source code is free speech: writing a program is another way of expressing yourself, just like writing a novel or a poem.

Therefore, we bring you a small bit of free speech right here for your viewing enjoyment:

DeCSS source code

#!/usr/bin/perl
# 472-byte qrpff, Keith Winstein and Marc Horowitz 
# MPEG 2 PS VOB file -> descrambled output on stdout.
# usage: perl -I :::: qrpff
# where k1..k5 are the title key bytes in least to most-significant order

s''$/=\2048;while(<>){G=29;R=142;if((@a=unqT="C*",_)[20]&48){D=89;_=unqb24,qT,@
b=map{ord qB8,unqb8,qT,_^$a[--D]}@INC;s/...$/1$&/;Q=unqV,qb25,_;H=73;O=$b[4]<<9
|256|$b[3];Q=Q>>8^(P=(E=255)&(Q>>12^Q>>4^Q/8^Q))<<17,O=O>>8^(E&(F=(S=O>>14&7^O)
^S*8^S<<6))<<9,_=(map{U=_%16orE^=R^=110&(S=(unqT,"\xb\ntd\xbz\x14d")[_/16%8]);E
^=(72,@z=(64,72,G^=12*(U-2?0:S&17)),H^=_%64?12:0,@z)[_%8]}(16..271))[_]^((D>>=8
)+=P+(~F&E))for@a[128..$#a]}print+qT,@a}';s/[D-HO-U_]/\$$&/g;s/q/pack+/g;eval

Gallery of DeCSS Descramblers

Dr. David S. Touretzky, (of the Computer Science Department, Carnegie Mellon University), has created a website that is a gallery of DeCSS descramblers.

His website asks that it be quoted as follows (it's a scholarly publication):

Touretzky, D. S. (2000)
Gallery of CSS Descramblers.
Available: http://www.cs.cmu.edu/~dst/DeCSS/Gallery, (17 Oct 2002).

The gallery has a number of different implementations of programs that decrypt CSS-encrypted material, available in a number of different formats (including C, Perl, spoken, in music, and verilog). I got the code above from his site.

http://www-2.cs.cmu.edu/~dst/DeCSS/Gallery/

DeCSS (no. I mean the other DeCSS... :)

So basically there was this guy, and he didn't like what the MPAA was doing, but he didn't want to go to jail.

But he was really smart and knew that the MPAA was taking everyone to court who either had a copy of DeCSS up on their webpage or who linked to a copy of DeCSS.

So he went and invented DeCSS. or rather, a different DeCSS, one that takes CSS formatting out of webpages. You see, his version is unquestionably legal (at least to the MPAA), and has nothing to do with the ContentScramblingSystem that is used on DVDs.

Do you see where we're going with this?

Anyhow, so basically he was (still is?) encouraging people to download copies of his DeCSS and put them up online. that way the MPAA will try to take thousands of people to court who have a copy of the webpage-modifying program :)

And that guy? his webpage is here: http://www.pigdog.org/decss/

you can even get a few lines of html from his page that will put a button on your webpage like this:

RobinsonTryon - 17 Oct 2002