Abstract
Error diffusion method is a major stream in digital halftoning, but unpleasant textures of output images, called “worms” and “fingerprints”, have been prevention of higher halftoning process. In particular, the worms are so noticeable in highlight area that they are major causes of graininess of output image. This paper proposes easy ways to reduce those unpleasant textures and blend advantages of error diffusion and conventional screen. The proposed modified algorithm's main intention is to employ a sine-wave whose amplitude and frequency change suitably according to input pixels. The worms are forced to be arranged by adding the sine-wave's amplitude before thresholding. In this paper, experimental results are reported and the image qualities are discussed as compared with previous methods.
