Method of generating a multiplexed image for printing
AssigneesHID Global CID SAS, Centre National De La Recherche Scientifique, Universite Jean Monnet Saint Etienne
InventorsStéphane Ayala, Nathalie Destouches, Mathieu Hébert, Nicolas Dalloz
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Abstract
A method of generating a multiplexed image for printing that can be observed in a plurality of modes includes determining a finite shape of a multiplexed palette in a combined color space. The contrast of the multiplexed image in each mode can be optimized by determining a maximum volume hyperrectangle enclosed in the finite shape. Gamut mapping to this maximum volume hyperrectangle allows for generation of a multiplexed image that has a maximum contrast and is free from artifacts caused by an interdependency between the colors in each mode. Performing a dimensionality reduction using PCA allows for reducing the complexity of the optimization problem.
Claims18
A method of generating a multiplexed image for printing that can be observed in a plurality of modes and can be printed using a laser marking apparatus, the method comprising:
- receiving a plurality of input images;
- combining the plurality of input images to form a multiplexed input image;
- retrieving a multiplexed palette from a memory, the multiplexed palette including a plurality of images that can be printed on a substrate surface by varying one or more parameters of the laser marking apparatus, each image being observable in the plurality of modes and having a plurality of color values corresponding to the plurality of modes;
- determining a finite shape of the multiplexed palette in a combined color space based on the color values of the plurality of images;
- determining a maximum volume hyperrectangle enclosed in the finite shape of the multiplexed palette;
- performing gamut mapping to map color values of the multiplexed input image to color values inside the maximum volume hyperrectangle;
- and
- obtaining the multiplexed image for printing based on the gamut-mapped color values of the multiplexed input image.
Dependencies are inferred from the claim text.