Sliding-block decodable encoders between (d,k) runlength-limited constraints of equal capacity

We determine the pairs of (d,k)-constrained systems, S(d,k) and S(d/spl circ/,k/spl circ/), of equal capacity, for which there exists a rate 1:1 sliding-block-decodable encoder from S(d,k) to S(d/spl circ/,k/spl circ/). In all cases where there exists such an encoder, we explicitly describe the encoder and its corresponding sliding-block decoder.