Lossless sliding-block compression of constrained systems

A method is presented for designing lossless sliding block compression schemes that map constrained sequences onto unconstrained ones The new compression scheme is incorporated into a coding technique for noisy constrained channels which has appli cations to magnetic and optical storage As suggested recently by Immink the use of a lossless compression code can improve the performance of a modi ed concate nation scheme where the positions of the error correcting code and constrained code are reversed primarily in order to eliminate error propagation due to the constrained code Examples are presented that demonstrate the advantage of using sliding block compression over block compression in a noisy constrained setting