METHODS FOR GENERATING BLUE-NOISE DITHER MATRICES FOR DIGITAL HALF-TONING

Blue-noise dither halftoning methods have been found to produce images with pleasing visual characteristics. Results similar to those genera ted with error-diffusion algorithms can be obtained using an image pro cessing algorithm that is computationally much simpler to implement. T he various techniques that have been used to design blue-noise dither matrices are reviewed and compared. In particular, a series of visual cost function based methods and several techniques that involve design ing the dither matrices by analyzing the spatial dof distribution are discussed. Ways to extend the basic blue-noise dither techniques to mu ltilevel and color output devices are also described, including recent advances in the design of jointly optimized color blue-noise dither m atrices. (C) 1997 SPIE and IS&T. [S1017-9909(97)00602-8].