Color Imaging and Pattern Hiding on a Metallic Substrate

摘要

We present a new approach for the reproduction of color imagesrnon a metallic substrate that look bright and colorful under specularrnreflection observation conditions and also look good under nonspecularrnreflection observation conditions. We fit amounts of bothrnthe white ink and the classical cyan, magenta and yellow inksrnaccording to a formula optimizing the reproduction of colorsrnsimultaneously under specular and non-specular observationrnconditions. In addition, we can hide patterns such as text orrngraphical symbols in one viewing mode, specular or non-specular,rnand reveal them in the other viewing mode. We rely on the tradeoffrnbetween amounts of white diffuse ink and amounts of cyan,rnmagenta and yellow inks to control lightness in specular and inrnnon-specular observation conditions. Further effects are grayscalernimages that alternate from a first image to a second independentrnimage when tilting the print from specular to non-specular reflectionrnobservation conditions. Applications comprise art and entertainment,rnpublicity, posters, as well as document security.