David Scott occupies a unique niche in the world of data compression. He is very interested in how one can adapt existing compression technologies to be bijective, a term you can find defined on his web page. The stated motivation for this is to increase the difficulty of breaking an encrypted version of the file. On this page, David makes a first pass at modifying BWT to be bijective. He doesn’t quite get there, but feels that he has taken some good steps towards his goal.

http://bijective.dogma.net/compres9.htm