A new moire smoothing method for color inverse halftoning

The color inverse halftoning technique was developed for the use of scanned color halftone images in digital applications, which is basically a smoothing method of halftone patterns. Smoothing of the moire phenomenon in color halftoning unfortunately leads to excessive blurring of the boundaries because moire patterns form very low-frequency peaks in the spectral domain. An adaptive method for smoothing the moire patterns in image space is proposed in this paper, which uses moire strength information that is determined off-line by analyzing interference between different color halftone patterns. The information is stored in tables and is looked up directly with color values of each pixel, so the proposed method works very fast. Through several experiments, we found that our experimental method smoothed moire patterns well without blurring the boundaries much.