摘要 |
The present invention provides a lossless coding scheme that maps unconstrained binary sequences into sequences that obey the (d,k)-RLL constraint while offering a degree of DC control. In the preferred embodiment, the channel encoder is a state machine which uses a single "overlapping" table for all states rather than using multiple tables. Recognizing that a subset of codewords in a first state xi are identical to a subset of codewords in the second state xj, the overlapping encoding table uses identical addresses for the subset of identical codewords in the first and second state. Thus addresses for more than one state may point to a single codeword. A number of input bytes can be encoded into two different codewords which have different parity of ones, thus allowing for DC control. Decoding is carried out in a state-independent manner.
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