Color model
AssigneeHewlett-Packard Development Company, L.P.
InventorsPeter Morovic, Jan MOROVIC, Xavier FARINA VARGAS, Juan Manuel GARCIA REYERO VIÑAS
Life of this patent
Estimating the term…
Abstract
Certain methods and systems are described to provide color modelling. This color modelling applies to halftone images. In one example, a correction parameter for a color model is determined by minimizing a distance metric between a set of estimated spectral reflectance values and a set of measured spectral reflectance values to generate a multi-dimensional correction parameter. This enables a color model to be used to map at least one Neugebauer Primary area coverage value to at least one spectral reflectance value.
Claims15
A computer-implemented method comprising:
- obtaining a plurality of measured spectral reflectance values,
- each value being representative of a measured spectral reflectance of a halftone portion of a printed output generated by a particular printing device,
- each halftone portion being printed with one or more printing fluids at a particular area coverage, one or more printing fluids at a particular area coverage being expressed as a Neugebauer Primary area coverage value for printing;
- deriving parameters for at least one color model,
- the color model mapping at least one Neugebauer Primary area coverage value to at least one spectral reflectance value;
- computing estimated spectral reflectance values by applying the color model to the Neugebauer Primary area coverage values for printing;
- minimizing a distance metric between the estimated spectral reflectance values and the measured spectral reflectance values to generate a multi-dimensional correction parameter;
- and
- updating the color model to include the multi-dimensional correction factor.
A system comprising:
- an interface for receiving a plurality of measured spectral reflectance values,
- each measured spectral value being associated with a Neugebauer Primary area coverage vector, each entry in the vector being representative of an area coverage for a Neugebauer Primary;
- a color model arranged to map a Neugebauer Primary area coverage vector to a reflectance spectrum;
- a configuration component communicatively coupled to the interface and arranged to derive one or more parameters for the color model,
- a mapping component arranged to use the color model to map a Neugebauer Primary area coverage vector to a reflectance spectrum;
- a correction component arranged to receive two sets of spectral reflectance values and to minimize a distance metric based on the received values to generate a multi-dimensional correction parameter;
- and
- a color processor arranged to:
- instruct the mapping component to generate one or more estimated spectral reflectance values based on the plurality of Neugebauer Primary area coverage vectors associated with the measured spectral reflectance values,
- instruct the correction component to generate a multi-dimensional correction parameter based on the estimated spectral reflectance values and the measured spectral reflectance values, and
- instruct the configuration component to update the color model based on a multi-dimensional correction parameter generated by the correction component.
A non-transitory computer-readable storage medium storing instructions that, when executed by one or more processors, cause the one or more processors to:
- derive parameters for at least one color model,
- the color model mapping at least one Neugebauer Primary area coverage value to a spectral reflectance value,
- the parameters being derived from a plurality of measured spectral reflectance values, each measured spectral value being associated with at least one Neugebauer Primary area coverage value;
- compute estimated spectral reflectance values by applying the color model to the Neugebauer Primary area coverage values associated with the measured spectral reflectance values;
- minimize distance metric between the estimated spectral reflectance values and the measured spectral reflectance values to generate a multi-dimensional correction parameter;
- and
- update the color model to include the multi-dimensional correction factor.
Dependencies are inferred from the claim text.