Achieving ink cost saving for printing devices by taking visual appearance and real ink costs into account
A user defines the real costs for each of the individual inks used in printer and also defines a tolerance level for visual acceptance, defined in CIE units of DeltaE2000. Then, an algorithm performs a search through all nodes of the device link profile and for each node it tries to find an ink combination that creates less costs and is still within the given visual tolerance (<dE2000).
1. A method for generating a device ink profile for ink cost saving in a printing device, comprising:
receiving and taking into account a price for each of a plurality of individual inks used by said printing device;
receiving and taking into account a user defined tolerance level for visual acceptance in a print produced by said printing device, wherein said tolerance level is defined using the International Commission on Illumination (CIE) DeltaE2000 color difference metric; and
with a processor, performing a search through all nodes of a device link profile and, for each node, finding an ink combination that reduces ink costs while remaining within said tolerance level for said visual acceptance by:
creating a neutral 1:1 device link in an n color (nCLR), where n=a number of inks;
starting with a first node in the device link, using chart measurement data to calculate a resulting International Commission on Illumination (CIE) L*a*b* color space value;
modifying an ink recipe for this node ink-by-ink by reducing ink percentage and/or replacing large light percentages with smaller dark ink amounts to reduce total ink costs;
recalculating the L*a*b* while DeltaE2000 is still within a given tolerance; and
going to a next node in the device link and calculating a resulting L*a*b* value.
2. The method of claim 1 , further comprising:
providing an additional color management module (CMM) that modifies ink separations using said device link profile.
3. The method of claim 2 , wherein said CMM comprises a seven color (7CLR) CMYKlclmlk_to_CMYKlclmlk profile.
4. The method of claim 2 , wherein said device link comprises:
an nCLR-to-nCLR device link that is used to apply relative changes to the ink separations, where n is the number of colors (CLRs) of inks used for printing.
5. The method of claim 2 , further comprising:
embedding a set of measurements in an existing International Color Consortium (ICC) profile of output inks and overprint combinations.
6. The method of claim 1 , further comprising:
a user, via a user interface, defining the price for each individual ink of said plurality of and the tolerance level for visual acceptance.
7. The method of claim 1 , further comprising:
said processor implementing a user interface slider for use in connection with said device link, said user interface slider allowing a user to find a desired balance of print quality and ink usage wherein, in response to a user setting, the International Commission on Illumination (CIE) DeltaE2000 color difference metric value is adjusted by said processor between a better print quality setting that uses more of said ink and a reduced ink usage setting that compromises print quality.
8. An apparatus for generating a device ink profile for ink cost saving in a printing device, comprising:
a processor performing a search through all nodes of a device link profile and, for each node, finding an ink combination that reduces ink costs while remaining within a predetermined tolerance level for visual acceptance by:
creating a neutral 1:1 device link in an n color (nCLR), where n=a number of inks;
starting with a first node in the device link, using chart measurement data to calculate a resulting International Commission on Illumination (CIE) L*a*b* color space value;
modifying an ink recipe for this node ink-by-ink by reducing ink percentage and/or replacing large light percentages with smaller dark ink amounts to reduce total ink costs;
recalculating the L*a*b* while DeltaE2000 is still within a given tolerance; and
going to a next node in the device link and calculating a resulting L*a*b* value.
9. The apparatus of claim 8 , further comprising:
an additional color management module (CMM) that modifies ink separations using said device link profile.
10. The apparatus of claim 9 , wherein said CMM comprises a seven color (7CLR) CMYKlclmlk_to_CMYKlclmlk profile.
11. The apparatus of claim 9 , wherein said device link comprises:
an nCLR-to-nCLR device link that applies relative changes to the ink separations, where n is the number of colors (CLRs) of inks used for printing.
12. The apparatus of claim 9 , further comprising:
a set of measurements embedded in an existing International Color Consortium (ICC) profile of output inks and overprint combinations.
13. The apparatus of claim 8 , further comprising:
a user interface for defining the price for each individual ink of said plurality of inks and the tolerance level for visual acceptance.
14. The apparatus of claim 8 , further comprising:
said processor providing a user interface slider for use in connection with said device link, said user interface slider allowing a user to find a desired balance of print quality and ink usage wherein, in response to a user setting, the International Commission on Illumination (CIE) DeltaE2000 color difference metric value is adjusted by said processor between a better print quality setting that uses more of said ink and a reduced ink usage setting that compromises print quality.
15. A method for achieving ink cost savings in a printer, comprising:
a processor iteratively reducing a value that determines how much ink is to be used in each separate layer of a print job by a predetermined amount, wherein print data is received after the print job is separated into each of a plurality of different inks that together the comprise the ink that is used to print said print job; and
said processor checking a resulting color that is to be printed after the ink to be used in each separate layer is reduced to determine if a resulting color is within a given user-defined tolerance, wherein the resulting color is not exactly identical to an original color, and wherein the resulting color falls within said user-defined tolerance.
16. The method of claim 15 , further comprising:
said processor accessing a database of prices of the plurality of different inks;
said processor reducing a value that determines an amount of ink for a most expensive ink first to reduce the overall ink cost per page;
said processor comparing a color that results from said reducing of a value that determines an amount of ink for said most expensive ink with the original color to determine if the color that results falls within said user-defined tolerance;
when the color that results falls within said user-defined tolerance, the processor reducing the value that determines the amount of ink further until it finds that a distance in color space is bigger than the user-defined tolerance;
thereafter, the processor reducing a value that determines the amount of a second most expensive ink; and
the processor continuing accordingly until no more reduction in ink is possible within the user-defined tolerance.
17. An apparatus for achieving ink cost savings in a printer, comprising:
a processor configured for iteratively reducing a value that determines how much ink is to be used in each separate layer of a print job by a predetermined amount, wherein print data is received after the print job is separated into each of a plurality of different inks that together the comprise the ink that is used to print said print job; and
said processor configured for checking a resulting color that is to be printed after the amount of ink to be used in each separate layer is reduced to determine if a resulting color is within a given user-defined tolerance, wherein the resulting color is not exactly identical to an original color, and wherein the resulting color falls within the user-defined tolerance.
18. The apparatus of claim 17 , further comprising:
said processor configured for accessing a database of prices of the plurality of different inks;
said processor configured for reducing a value that determines an amount of ink for a most expensive ink first to reduce overall ink cost per page;
said processor configured for comparing a color that results from said reducing of a value that determines an amount of ink for said most expensive ink with the original color to determine if the color that results falls within said user-defined tolerance;
when the color that results falls within said user-defined tolerance, the processor configured for reducing the value that determines the amount of ink further until it finds that a distance in color space is bigger than the user-defined tolerance;
thereafter, the processor configured for reducing a value that determines the amount of a second most expensive ink; and
the processor configured for continuing accordingly until no more reduction in ink is possible within the user-defined tolerance.