Abstract: Certain examples relate to a method of printing management. An image is received for printing and printing parameters to print the image are determined. The image is printed onto a substrate using the printing parameters, and the image is printed with an embedded code corresponding to the printing parameters. The printing parameters are associated with the embedded code such that the printing parameters are retrievable from the embedded code.

Abstract: In some examples, in a component space defined by a plurality of edges, a system defines a first point on a first edge of the plurality of edges, the first point dividing the first edge into a first portion in which a first component is to be used in producing an output by an output device, and a second portion in which the first component is not used in producing an output by the output device, where a first space inside the component space corresponding to the first portion is to use the first component in producing an output by the output device, and a second space inside the component space corresponding to the second portion is to not use the first component in producing an output by the output device.

Abstract: Disclosed is a non-transitory computer readable storage medium, a computer-implemented method and an imaging color profile of an imaging apparatus. A processor retrieves the color profile of the imaging apparatus from data storage, the color profile comprising a first plurality of associations between a first plurality of color values in a first color space and a second plurality of color values in a second color space. The processor receives input data indicating a determined association, the determined association being an association between a first determined color value in the first color space and a second determined color value in the second color space. The processor performs an update process to update the first plurality of associations, the update process comprising performing an interpolation process using the determined association and an association of the first plurality of associations.

Abstract: Methods of image compression are described. A stream of color image data is filtered with a prediction routine using a pixel neighborhood. The filtered stream of color image data is sorted with a block sorting routing. A version of the color image data is compressed based on the sorted and filtered stream of color image data.

Abstract: In an example, a method includes acquiring data representing an article to be printed, the data comprising an element set associated with a print addressable location, the element set comprising a first element subset and a second element subset, wherein the first element subset and the second element subset comprise an element identifying a print material selection which is associated with a probability that the print material selection is to be applied to the associated print addressable location. The method further includes determining a first set of cumulative probability values associated with the elements of the first element subset and determining a second set of cumulative probability values associated with the elements of the second element subset. The first set of cumulative probability values may span a first predetermined value range and the second set of cumulative probability values may span a second predetermined value range.

Abstract: In examples, a method includes receiving print image data representing an image to be printed and selectively modifying at least one of an initial background print agent color plane and an initial image print agent color plane to determine a modified color plane.

Abstract: Certain examples relate to a method of color matching by confirming a color-rendering device. Color reproduction parameters are determined for a reference and target color-rendering device. A color matching parameter is determined for the target color-rendering device based on a comparison of the color reproduction parameter for the target color-rendering device with the corresponding color reproduction parameter of the reference color-rendering device. The color-rendering device is confirmed dependent on the color matching parameter. Color resources of the target color-rendering device are configured such that a rendering of a color image on the target color-rendering device replicates a rendering of the color image on the reference color-rendering device.

Abstract: Certain examples relate to a method of printing management. An image is received for printing and printing parameters to print the image are determined. The image is printed onto a substrate using the printing parameters, and the image is printed with an embedded code corresponding to the printing parameters. The printing parameters are associated with the embedded code such that the printing parameters are retrievable from the embedded code.

Abstract: A method comprises obtaining at a processor a first color gamut and a second gamut represented in a first color space. The first and second gamuts are represented as first and second objects in a second color space, with each object comprising a plurality of nodes. For each node, an index is provided indicating a position in the first color space to which that node corresponds. A further index is provided indicating a position, in the first color space, of the node relative to at least one other node of the object to which the node belongs. Each node of the first object corresponds with a node of the second object providing a mapping between the objects, using the further index. The index of at least one of the first object nodes is adjusted based on the corresponding node of the second object producing a mapping between the gamuts.

Abstract: In examples, a method includes receiving print image data representing an image to be printed and selectively modifying at least one of an initial background print agent color plane and an initial image print agent color plane to determine a modified color plane.

Abstract: In an example, a method includes acquiring data representing an article to be printed, the data comprising an element set associated with a print addressable location, the element set comprising a first element subset and a second element subset, wherein the first element subset and the second element subset comprise an element identifying a print material selection which is associated en with a probability that the print material selection is to be applied to the associated print addressable location. The method further includes determining a first set of cumulative probability values associated with the elements of the first element subset and determining a second set of cumulative probability values associated with the elements of the second element subset. The first set of cumulative probability values may span a first predetermined value range and the second set of cumulative probability values may span a second predetermined value range.

Abstract: Methods of image compression are described. A stream of color image data is filtered with a prediction routine using a pixel neighborhood. The filtered stream of color image data is sorted with a block sorting routing. A version of the color image data is compressed based on the sorted and filtered stream of color image data.

Abstract: Certain examples described herein relate to generating a color mapping between a source color gamut within a source color space and a target color gamut within a target color space. Gamuts may be set based on a color rendering device. In examples, a sequence of forward color transformations that transform the source color gamut is defined, along with a sequence of inverse color transformations that transform the target color gamut. A gamut mapping is applied between the output of the forward color transformations and the output of the inverse color transformations, wherein the color mapping is usable by a computing device to map between the source and target color spaces.

Abstract: Certain examples described herein relate to printer calibration. In certain cases, measurement data is received, the measurement data indicative of an adjustment to be applied to a given colorant in a set of colorants printable by a printing system. In certain examples, a Neugebauer primary area coverage (NPac) vector comprising an area coverage of a first Neugebauer primary (NP) is obtained. Based on the received measurement data, the NPac vector is adjusted by decreasing the area coverage in the NPac vector of the first NP and increasing an area coverage in the NPac vector of a second NP. The first NP and the second NP correspond to colorant combinations that differ by a predetermined amount of the given colorant.

Abstract: A method is described in which printing instructions representing printing content to be printed by a printing system are received, the printing system comprising a dispenser to dispense printing material. Whether to perform a first mapping process or a second mapping process is then selected. The first mapping process comprises mapping an indicator to a first dispensing process to dispense printing material from the dispenser to produce content according to a content characteristic of the printing content at a given location, and the second mapping process comprises mapping the indicator to a second dispensing process to dispense printing material to produce content according to the content characteristic at the given location. The first dispensing process is different than the second dispensing process. The indicator represents the content characteristic. The method also comprises performing the selected mapping process.

Abstract: A method is described. The method comprises determining a lightness coordinate value corresponding to a first color value along a black-white axis in an input device color space. A set of color values corresponding to the lightness coordinate value, in the input device color space is determined. A subset of the set, based on the respective angular positions of the color values in the set and an angular position of the first color value is determined. The method comprises deriving a set of print color space values of a target printing system comprising print color space values corresponding to the subset and a color value corresponding to the position of the lightness coordinate value, based on a predetermined association between input device color space values and print color space values. The method comprises determining a given print color space value corresponding to the first color value based on the derived set of print color space values.

Abstract: Methods for printer color calibration are disclosed. A nominal Neugebauer Primary area coverage (NPac) vector from an NPac space is then determined from a color mapping, the nominal NPac vector corresponding to a given color value in a color space. One or more colorant calibration factors each associated with a color of colorant are received; the calibration factors representing operational characteristics of the printer. One or more optimization metrics for constraining desired properties of an objective calibrated NPac vector to be generated are also received. The calibrated NPac vector is generated based on the nominal NPac vector such that: the generated calibrated NPac vector is convex; and for each given color of colorant the usage of colorant associated with the generated calibrated NPac vector is equal to the product of usage of colorant associated with the nominal NPac vector; and the calibration factor for the given color of colorant.

Abstract: Certain examples described herein relate to printer calibration. In certain cases, measurement data is received, the measurement data indicative of an adjustment to be applied to a given colorant in a set of colorants printable by a printing system. In certain examples, a Neugebauer primary area coverage (NPac) vector comprising an area coverage of a first Neugebauer primary (NP) is obtained. Based on the received measurement data, the NPac vector is adjusted by decreasing the area coverage in the NPac vector of the first NP and increasing an area coverage in the NPac vector of a second NP. The first NP and the second NP correspond to colorant combinations that differ by a predetermined amount of the given colorant.

Abstract: Methods for printer color calibration are disclosed. A nominal Neugebauer Primary area coverage (NPac) vector from an NPac space is then determined from a color mapping, the nominal NPac vector corresponding to a given color value in a color space. One or more colorant calibration factors each associated with a color of colorant are received; the calibration factors representing operational characteristics of the printer. One or more optimization metrics for constraining desired properties of an objective calibrated NPac vector to be generated are also received. The calibrated NPac vector is generated based on the nominal NPac vector such that: the generated calibrated NPac vector is convex; and for each given color of colorant the usage of colorant associated with the generated calibrated NPac vector is equal to the product of usage of colorant associated with the nominal NPac vector; and the calibration factor for the given color of colorant.

Abstract: A method is described. The method comprises determining a lightness coordinate value corresponding to a first color value along a black-white axis in an input device color space. A set of color values corresponding to the lightness coordinate value, in the input device color space is determined. A subset of the set, based on the respective angular positions of the color values in the set and an angular position of the first color value is determined. The method comprises deriving a set of print color space values of a target printing system comprising print color space values corresponding to the subset and a color value corresponding to the position of the lightness coordinate value, based on a predetermined association between input device color space values and print color space values. The method comprises determining a given print color space value corresponding to the first color value based on the derived set of print color space values.