Methods of a coarse-scan/fine-print character reproduction with compression

摘要

A coarse scanning device produces analog signals that are encoded and compressed to distinguish between and represent the white background and potentially the all black elements of the character by run length codes and at least the edge of the black character by grey level values. The grey level information is decoded to activate a fine print device where the numer of print dots in a matrix is equal to the grey level values. The placement of the print dots are biased according to pattern matrices designed to bias the dots toward the character. The pattern matrices are acquired by determining the sums of the grey level values of various groups of picture elements peripheral to the picture element being decoded.