Method and apparatus for compressing binary data using pattern matching encoding

摘要

In a method and an apparatus for pattern matching encoding disclosed a font bit map library is provided separately from a temporary updating library, in which temporary bit map pattern data capable of being updated according to a character pattern cut out from input binary image data is stored. In the font bit map library is stored font bit map library pattern data of an input character pattern font or a font designated by the user. A pattern matching process on the character pattern, is executed by comparing the character pattern with temporary bit map pattern data and font bit map pattern data. The character pattern is newly registered in the temporary updating library, when it is judged as being matched with only the temporary bit map pattern or as being matched with neither of the temporary bit map pattern or the font bit map pattern. It is possible to improve data compressibility without sacrifice in image quality.