Patent ID: 7876241

Claim:
An apparatus for processing data recorded on a recording layer in an information storage medium, the apparatus comprising: a data modulator configured to perform a modulation operation of source data into a modulated code stream of code words where a minimum run length limit is confined to “d” and a maximum run length limit is confined to “k”, “d” and “k” being positive integers; and a optical pickup configured to emit a light to the information storage medium to transfer data with respect to the information storage medium, wherein the modulation operation comprises changing at least one of a code word A and a code word B into another code word such that a sum of an endzero of the code word A and a leadzero of a code word B is greater than or equal to the minimum run length limit and is less than or equal to the maximum run length limit when the code word B is connected to a code word A, the code word A being a preceding code word, wherein the endzero is a number of successive zeros from least significant bits (LSBs) of the code word A to most significant bits (MSBs), and wherein the leadzero is a number of successive zeros from most significant bits (MSBs) of the code word B to least significant bits (LSBs).