Patent ID: 8970910
Filing Date: 2015-03-03
Classification: G06T,H04N

Abstract:
1. A computer-implemented method for generating a watermarked halftone image using 2 nd generation stochastic halftoning to binarize pixels, comprising: receiving a contone input image and watermark image data; determining seed locations based on a gray level of the input image at given locations within the image and based on a presence or absence of a watermark at those locations, where watermark regions have a first FM-to-AM transition threshold and non-watermark regions have a second FM-to-AM transition threshold; determining a tessellation based on the seed locations; calculating a halftone spot function to determine a spot function value for each pixel in the input image based on the tessellation determined by the seed locations; comparing an input pixel value to a co-located spot function value for each pixel in the input image to generate the watermarked halftone image; and outputting the watermarked halftone image.