Patent ID: 7262885
Filing Date: 2007-08-28
Classification: H04N

Abstract:
1. A halftone processor for converting a gray scale image comprising a plurality of in-bit pixels to a halftoned image comprising a plurality of n-bit pixel images, where m>n, the processor comprising: a memory storing a stochastic screen, the stochastic mask being a stochastic screen constrained by a checkerboard pattern, the checkerboard pattern constrained stochastic screen comprising a set of threshold values, each threshold value in the checkerboard pattern constrained stochastic screen corresponding to a gray level, each threshold value corresponding to a gray level between a first gray level (g a comparator receiving the gray scale image and the set of threshold values corresponding to the checkerboard pattern constrained stochastic screen, the comparator comparing, on a pixel-by-pixel basis, a value of each pixel in the gray scale image to a corresponding threshold value in the checkerboard pattern constrained stochastic screen to produce the halftoned image.