Patent ID: 8610958
Filing Date: 2013-12-17
Classification: H04N

Abstract:
1. A computer-based method for producing a printed authenticable color multi-ink multi-halftone image, comprising the steps of (a) selecting two halftoning methods h (b) selecting a color input image and an input color gamut; (c) positioning a message and determining its foreground and background regions within said input image; (d) gamut mapping by computation said input color gamut onto a printable destination gamut yielding gamut mapped input colors; (e) under a selected reference illuminant, establishing with an accurate ink spreading enhanced color prediction model colorimetric to ink surface coverages mappings m (f) by relying on said colorimetric to ink surface coverage mappings m (g) halftoning said multi-valued ink separations s (h) merging said message foreground and background regions of the halftoned ink separation layers p (i) printing said merged ink color separation layers q, thereby obtaining said color multi-ink multi-halftone image; where under the selected reference illuminant the message incorporated into the color multi-halftone image is hidden since its foreground and background regions are indistinguishable.