| 摘要 |
PROBLEM TO BE SOLVED: To efficiently a decompress LZW code by suppressing the number of times of registration processing in a character string table used as a dictionary. SOLUTION: A temporary buffer controller 502 stores a codeword in a temporary buffer 503 until the LZW codeword is a clear code or an end code, specifies a character string reference codeword referring an LZW code character string table 506 among a group of codewords stored in the temporary buffer 503, and then generates identification information to specify a codeword as a subject of registration in the character string table 506 from among the group of codewords in the temporary buffer 503. A character string table controller 504 determines whether or not a codeword read from the temporary buffer 503 is a subject of registration in the character string table 506, and when it is determined that the codeword is the subject of registration, the character string table controller 504 registers a new character string data, which is obtained by adding a head character of a currently decoded character string to a previously decoded character string, in an entry address position which is indicated by the codeword read from the temporary buffer and is present in the character string table 506. COPYRIGHT: (C)2011,JPO&INPIT
|
