摘要:
The present invention facilitates the calibration of printers and the color separation of input images into a set of inks by disclosing methods and systems for populating device-calibration lookup tables. The disclosed methods and systems rely on a comprehensive spectral prediction model predicting at a high accuracy the reflectance spectra of halftone ink patches. The spectral prediction model is composed of a first part predicting the reflection spectra as a function of physical (mechanical) surface coverages and of a second part comprising functions mapping nominal surface coverages to effective surface coverages for halftone patch wedges printed alone and halftone patch wedges printed in superposition with one or several solid inks. In addition, the disclosed methods and systems can be used to control printer actuation parameters in different types of printers e.g. liquid ink professional printers (offset, gravure, letterpress), electrophotographic printers, ink-jet printers, Thermal transfer printers and dye-sublimation printers.
摘要:
The present invention discloses methods and systems for printing by superposing a metallic ink and transparent inks. These methods and systems are useful for color separating images into superpositions of a metallic ink and transparent inks both for design purposes and for the creation and authentication of security documents, such as banknotes, checks, diploma, corporate documents, passports, identity cards, credit cards, product labels, optical disks, CDs, DVDs, packages of medical drugs, cosmetics, and alcoholic drink bottles. By combining a metallic ink and transparent inks, one may create printed images behaving dynamically: an image viewed under specular reflection may be considerably different from the same image viewed under non-specular reflection. Patterns which are either dark or hidden become highlighted under specular reflection, yielding interesting visual effects. Metallic inks allow therefore to create visually appealing dynamically changing color images. In addition, the inversion effect provided by metallic inks allows to enhance microstructures present in the image or to reveal hidden patterns. Since these effects are lost in photocopied documents, the disclosed methods, systems and security documents offer a high security against counterfeiting attempts.
摘要:
A method of generating an image incorporating a microstructure includes the steps of obtaining an original image, generating a microstructure, and rendering a region or the whole said original image with said microstructure. The operation of generating the microstructure includes an automatic synthesis of microstructure elements from original microstructure shapes.
摘要:
The present invention describes methods and apparatuses for creating superposition shape images by superposed base and revealing layers of lenslet gratings. The superposition shape images form a message recognizable by a human observer or by an image acquisition and computing device such as a smartphone. The superposition shape images may be created by different superposition techniques ranging from 1D moiré, 2D moiré and level-line moiré superposition techniques to lenticular image and phase shift superposition techniques. Moiré superposition techniques enable creating superposition shape images at different apparent depth levels. Applications comprise the protection of documents and valuable articles against counterfeits, the creation of eye-catching advertisements as well as the decoration of buildings and exhibitions.