Coding device and decoding device

Abstract

Embodiments of the invention allow relatively simple circuits to provide a coding device capable of coding longer bit-length data suitably for disk apparatus and a decoding device capable of decoding the data coded by the coding device. In one embodiment, a coding device comprises: a coder which, based on an M bits code string, produces an (M+1) bits coded string where each of the plural bits which may appear in the M bits code string is limited in run length; a preprocessor which produces an M bits code string by removing (N-M) bits respectively from predefined (N-M) positions of an incoming N bits code string and outputs the M bits code string to the coder; and a postprocessor which produces and outputs an (N+1) bits code string by inserting the (N-M) bits, which are removed by the preprocessor, into predefined (N-M) respective insertion positions of the (M+1) bits coded string output from the coder.

Dependencies are inferred from the claim text.