| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which can guarantee a high compression rate in the worst case. <P>SOLUTION: The image forming apparatus comprises: a basic dictionary memory means, an extended dictionary memory means; a first comparison means for comparing the data size of encoded data converted by a basic dictionary conversion means with a prestored threshold; an extended dictionary conversion means for converting a corresponding code group into an alternative code using an extended dictionary when it is determined that the data size is larger than the threshold; a data size determining means for determining whether the extended dictionary has reached the maximum data size when it is determined that the alternative code is not included in the extended dictionary; a dictionary extension means for adding a postscript of new alternative code in correspondence with a code group not included in the extended dictionary to the extended dictionary; and a postscript extended dictionary conversion means for converting a corresponding code group into an alternative code to which a postscript is added. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
