Samsung Electronics Co., Ltd.

Iqbal Mahboob

Jae-seong Shim

Hyun-Soo Park

Kiu-hae Jung

Ki-hyun Kim

Ki-Hyun Kim

A method of generating and allocating codewords includes allocating one of two selectable codewords band bas codeword 'b' when a preceding codeword 'a' and a following codeword &#x201c;b&#x201d; form a code stream X, in which the codewords band bhave opposite INV values which are parameters indicating whether the number of '1s' contained in a codeword is an odd number or an even number. When the code stream of the preceding codeword &#x201c;a&#x201d; and the following codeword bis X, and when the code stream of the preceding codeword &#x201c;a&#x201d; and the following codeword bis X, the codewords are allocated such that the INV values of Xand Xare maintained to be opposite when the preceding codeword &#x201c;a&#x201d; or the following codeword b(b) (bor b) should be replaced by another codeword in compliance with a predetermined boundary condition given between codewords. The codewords are allocated so that a DC suppression capability of the code stream can be maintained.

Code generation and allocation apparatus

Code generation and allocation method

A method of generating and allocating codewords includes allocating one of two selectable codewords band bas codeword 'b' when a preceding codeword 'a' and a following codeword &#x201c;b&#x201d; form a code stream X, in which the codewords band bhave opposite INV values which are parameters indicating whether the number of '1s' contained in a codeword is an odd number or an even number. When the code stream of the preceding codeword &#x201c;a&#x201d; and the following codeword bis X, and when the code stream of the preceding codeword &#x201c;a&#x201d; and the following codeword bis X, the codewords are allocated such that the INV values of Xand Xare maintained to be opposite when the preceding codeword &#x201c;a&#x201d; or the following codeword b(b)(bor b) should be replaced by another codeword in compliance with a predetermined boundary condition given between codewords. The codewords are allocated so that a DC suppression capability of the code stream can be maintained.

A method of generating and allocating codewords includes allocating one of two selectable codewords b and b as codeword &ldquo;b&rdquo; when a preceding codeword &ldquo;a&rdquo; and a following codeword &ldquo;b&rdquo; form a code stream X, in which the codewords b and b have opposite INV values which are parameters indicating whether the number of '1s' contained in a codeword is an odd number or an even number. When the code stream of the preceding codeword &ldquo;a&rdquo; and the following codeword b is X , and when the code stream of the preceding codeword &ldquo;a&rdquo; and the following codeword b is X , the codewords are allocated such that the INV values of X and X are maintained to be opposite when the preceding codeword &ldquo;a&rdquo; or the following codeword b (b ) (b or b ) should be replaced by another codeword in compliance with a predetermined boundary condition given between codewords. The codewords are allocated so that a DC suppression capability of the code stream can be maintained.

A code modulation and demodulation method includes removing a DC component of a code stream to be modulated when source data is recorded on an optical information storage medium and controlling a suppression of the DC component contained in the code stream when the source data is converted into a codeword to be recorded on an optical information storage medium. The method includes determining a control timing to suppress the DC component of the code stream to which the source data are converted, performing a code conversion at each control time for the DC component so that the code stream branches into a pair of branch code streams one of which extends in a direction where a running digital sum (RDS) of the code stream increases, and another one of which extends in the direction where the RDS of the code stream decreases, and selecting the path of the code stream that has a most bounded path around RDS '0' from the paths of the branch code streams each control time. By performing a regular DC suppression control when the source data is converted, and by selecting one of the branch code streams when the DC suppression control is performed, more DC components in the code stream can be effectively removed.

Growing community of inventors

Gujranwala, Pakistan

Iqbal Mahboob