METHOD AND APPARATUS FOR TRANSFORMING BIT-PLANE IMAGE, AND METHOD AND APPARATUS FOR INVERSE-TRANSFORMING BIT-PLANE IMAGE

摘要

PURPOSE: A method and an apparatus for converting a bit plane image, and a method and an apparatus for inversely converting a bit plane image are provided to increase correlation between adjacent pixels of a lower bit plane image during an image compressing process, thereby improving compression efficiency of the image. CONSTITUTION: A method for converting a bit plane image comprises the following steps. An input image is divided into n bit plane images(1010). n is a positive integer. a adjacent pixels in one direction between a column direction and a row direction are grouped to generate conversion processing units(1020). a is an integer larger than 1. Respective pixel values from a starting pixel to the bth pixel among a pixels in the conversion processing unit about each conversion processing unit are accumulated in the first direction selected between a plus direction and a minus direction. b is an integer smaller than a. Respective pixel values from the (b+1)th pixel to the final pixel in the conversion processing unit are accumulated in the second direction reverse to the first direction to convert pixel values of respective pixels in the conversion processing unit(1030).