This paper addresses to provide some of the new image processing techniques for color hardcopy. The first requirement for high quality color imaging, is how to reproduce a continuous tone. In the actual printing systems, we often encounter the false contours caused by a lack of gray levels or a jump of dot density. Here, we present a tone smoothing method using an improved pseudo-noise modulation as a countermeasure for such a printer with discontinuities in gray scale reproduction. The second requirement is to get the correct color rendition. We discuss two models on color correction and show the practical applications for full color printing. As the third requirement, a function to adjust color-tone as you like, will be needed for the future hardcopies and we shortly discuss the color adjusting problem based on human color perception. Lastly, we report our latest works on the new color coding technique, which can reconstruct a full color image from a single color image by utilizing the strong correlation characteristics among RGB signals.
"The New Color Image Processing Techniques for Hardcopy", Proc. SPIE 1075, Digital Image Processing Applications, (5 April 1989); doi: 10.1117/12.952653; https://doi.org/10.1117/12.952653