Abstract
JBIG or JBIG2 will be the highly efficient coding method for halftone images. However, the achieved compression ratios for error diffused images or blue dithered images are not satisfactory. In order to study the efficient coding scheme for such halftone images having pseudo-randomness, multi-level image coding, with halftoning after decoding, is proposed and examined. Here we analyzed the relation of information amount and its corresponding picture quality by controlling the image resolution and signal level precision under the assumption of lossy coding. The result shows that the similar compression ratio with JBIG2 can be achieved by the proposed method without affecting the image quality.