METHOD FOR IMAGE DATA COMPRESSION FOR TWO-COLOR IMAGES

A method for compressing digital image data present as matrix of M×N pixels, to a reduced data set, includes dividing the matrix of M×N pixels into blocks of u×v pixels, classifying the blocks of u×v pixels into blocks containing only pixels of one block color or single-color blocks, blocks containing pixels of a foreground color and pixels of a background color or two-color blocks, and blocks containing pixels with more than two colors or multicolor blocks, and coding, in the image data of the single-color blocks and the two-color blocks, by command code words and data words, pixel patterns which are repeated in at least one manner selected from the group consisting of from block to block and within a block, respectively.