Abstract
A resolution conversion method becomes necessary when images are exchanged between devices of different resolution, if devices are binary devices. However, because there are more high frequency patterns in dithered images than in facsimile images, many resolution conversion methods can not obtain satisfactory image quality when applied to dithered images. In this paper, we proposed a shrinking method for dithered images by Bayer mask. In our method, to compensate the difference of luminances between an original dithered image and the converted image, the similar technique as the Δ-Σ modulation method is introduced. Simulation results show that our method can obtain higher image quality than PRES or conversion method based on Hadamard transform.
