Multilayer white printing with white-balance
View Patent ↗White-balance is improved when printing on colored media, while minimizing the time and use of costly materials required by present approaches. In an embodiment, the typical solid white fill or background layer is altered by including in the white layer one or more of the other colors already available in the printer to shade this layer. Thus, a small amount of cyan, for example, helps balance a pink-ish (red) media; yellow is used for blue media; and magenta is used for green media; as well as combinations thereof. A combination of transparent process inks and opaque white helps to maintain brightness (luminosity).
1. A method for printing an image on a substrate with a printed having an inkset, wherein the inkset includes a plurality of inks for a printer having white ink and at least two inks having colors other than white, the substrate having a particular color other than white, the method comprising:
receiving from a user a media identifier that uniquely identifies a media type and the particular color of the substrate;
retrieving from a configuration file, based at least on the particular color of the media type identified by the media identifier, a first offset color value for a first offset color;
wherein the first offset color value indicates an amount of each of the at least two inks having colors other than white used by the printer;
in a first pass, printing on the substrate of the identified media type a first layer of the white ink mixed with the amount of each of the at least two inks having colors other than white indicated by the first offset color value;
wherein the printed first layer of mixed ink appears as a neutral color, so that the particular color of the substrate is not visible; and
in a second pass, printing the image on top of the printed first layer;
wherein the colors of the image are not modified based on the particular color of the substrate.
2. The method of claim 1 , further comprising adding an entry to the configuration file for the media type of the particular color, further comprising:
printing a layer of the white ink on a test piece of substrate of the media type;
determining that the layer of white appears as comprising a second color hue;
measuring the second color hue to determine a second color hue value;
determining a third offset color value of a third offset color based on the second color hue value, wherein the third offset color value indicates an amount of each of the at least two inks having colors other than white to mix with the white ink; and
storing in the entry of the configuration file the third offset color value in association with the media type.
3. The method of claim 2 , wherein the second color hue is measured by a spectrophotometer, a densitometer, or a camera to determine the second color hue value.
4. The method of claim 2 , wherein the second color hue value comprises a red, green, and blue (RGB) value.
5. The method of claim 2 , wherein determining the third offset color value comprises determining an inverse of the second color hue value.
6. The method of claim 2 , wherein the third offset color value is stored in the configuration file entry as an RGB value.
7. The method of claim 2 , wherein the third offset color value is stored in the configuration file entry as a cyan, magenta, and yellow (CMY) value.
8. The method of claim 1 , further comprising:
determining the amount of each of the at least two inks having colors other than white to mix with the white ink to form a neutral layer, further comprising:
looking up a second offset color value in a white balance profile based on the first offset color value, wherein the white balance profile was previously created for the type of ink being used by the printer; and
determining the amount of each of the at least two inks having colors other than white indicated by the second offset color value.