Patent ID: 6871928

Claim:
A method of printing comprising: partitioning a half-toned black bit map into a plurality of N-pixel tiles, each N-pixel tile having a marked pixel count M, and wherein the half-toned black bit map is produced pursuant to a predetermined half-toning procedure; for each N-pixel tile, determining whether an N-pixel tile comprises a portion of a half-toned uniform region; generating a candidate pixel array comprising a plurality of N-pixel candidate tiles respectively associated with the N-pixel image tiles, wherein an N-pixel candidate tile includes marked pixels only if the associated N-pixel image tile comprises a portion of a half-toned uniform region and the number of marked pixels in the associated N-pixel image tile is at least a predetermined percentage of N, and wherein the number of marked pixels in some of N-pixel candidate tiles having marked pixels is less than the marked pixels of the associated N-pixel image tile; printing black at pixel locations identified by the black bit-map; and printing a non-black color at selected ones of pixel locations identified by the candidate pixel array.