Abstract: A method for determining lattice points to be referenced to prepare the correspondence defining data, said method including steps of prescribing a smoothness evaluation function which has a function form differing depending on each region in the color gamut to which the lattice point to be evaluated belongs and also contains a constraint condition that the closer the lattice point is to the boundary of the region of the color gamut, the more the evaluated value decreases as the result of its movement, optimizing the arrangement of lattice points in the device-independent color space by improving the rating of the smoothness evaluation function, with the lattice point position information in the low-dimensional color space varied, and determining lattice points to be referenced to prepare the correspondence defining data in the optimized state.

Abstract: A system is configured to calculate an evaluation index of sample ink amount data from a color difference evaluation index and an image quality evaluation index and create a profile on the basis of a sample with a high rating value. When the image quality evaluation index is predicted, the image quality evaluation index corresponding to any sample ink amount data is estimated based on a profile produced on the basis on actual evaluation. A printer driver is configured to create a plurality of profiles by using different indices in this system and to perform color conversion by using the plurality of profiles. The plurality of profiles are appropriately selected according to the user's needs, printing conditions, and type of printing object image.

Abstract: A color patch that was printed based on a plurality of test ink quantity sets prepared in advance is image inputted; a graininess index is calculated based on the inputted color patch image; the graininess index on a printing medium obtained when printing is performed according to an arbitrary ink quantity set is predicted based on a graininess profile produced based on the corresponding relationship between the test ink quantity set and the graininess index.

Abstract: A method for producing a profile specifying the correspondence relationship of values in different color spaces, includes a step of acquiring a first correspondence relationship that is a correspondence relationship of a plurality of ink amounts and color values, a step of acquiring a plurality of grid points that are a plurality of grid points in a predetermined color space and for which a relative relationship between the adjacent grid points is defined, a step of acquiring a second correspondence relationship that is a correspondence relationship of the plurality of grid points and color values, a step of acquiring a third correspondence relationship that is a correspondence relationship of the plurality of grid points and ink amounts based on the first correspondence relationship and the second correspondence relationship, and a step of producing a profile specifying the third correspondence relationship.

Abstract: A method and apparatus for producing a color conversion profile for use in a color inkjet printer, a color laser printer, or the like. In one embodiment, a spectral printing model converter is used to sample ink amount data to spectral reflectance Rsmp(?). Using this spectral reflectance Rsmp(?), colorimetric values CV1, CV2 under two different viewing conditions are calculated, and an evaluation index EI that includes an index of color difference between the colorimetric values CV1, CV2 is calculated. I another embodiment, an evaluation index EI that includes an index of color difference between sample color represented by sample ink amount data and reference color obtained from a reference color patch is calculated. Sample ink amount data having the best evaluation index EI is then selected as a representative sample. Profiles are created from the plurality of selected representative samples.

Abstract: For correlating the specified colors and ink amount, the specified color data showing the color values of the specified colors are acquired, the ink amount data showing optional ink amount are converted into color values, evaluation index including the first evaluation index for evaluating the color difference between the color value of the specified colors under the standard observation condition and the color value of the ink amount and the second evaluation index for evaluating the color difference among color values obtained under a plurality of observation conditions are acquired, the question of whether the evaluation by the evaluation index meets the predetermined evaluation standard or not is evaluated, the conversion of the ink amount data and the acquisition of the evaluation index are repeated by correcting the ink amount until the evaluation standard is met, and the ink amount data of the ink amount having met the evaluation standard and the specified color data are correlated.

Abstract: A profile is created for making correspondence between a lattice point in an ink color space composed of ink colors and a lattice point in a device-independent color space by: defining a virtual force acting on a focused lattice point in a device-independent color space and obtaining the focused lattice position in a stable state reached when the virtual force acts on the focused lattice point; and working based on a transform model for transforming a lattice point in the ink color space into a lattice point in the device-independent color space to obtain a lattice point in an ink color space corresponding to a focused lattice position in the stable state and creating the profile by making correspondence between both.

Abstract: A server receives simulation condition input from a client computer, and in accordance with the simulation condition input creates display-use data indicating the result of the simulation, and sends the display-use data to the client. The print simulator of the server first converts the image data to ink quantities, and then converts the ink quantities to spectral reflectance of the print. Then, using the spectral reflectance of the print together with the print observation condition and the display device observation condition, there is created display-use data for simulating the appearance of the print under the print observation condition, under the display device observation condition.

Abstract: In order to create a profile that associates lattice points defined in an equipment-dependent color space with lattice points defined in an equipment-independent color space, a reference profile that associates a plurality of lattice points in the equipment-dependent color space with lattice points in the equipment-independent color space is retrieved. A virtual force that acts on a focused lattice point in the equipment-independent color space is defined, and a position at which the focused lattice point is located in a steady-state in which the virtual force acts on the focused lattice point is calculated. The reference profile is referenced in order to retrieve a lattice point in the equipment-dependent color space associated with the position of the steady-state focused lattice point. A profile is created by associating the position of each steady-state focused lattice point with a lattice point in the equipment-dependent color space.

Abstract: A second printing control unit is provided. If the setting information is the information of setting for avoiding the use of Cl ink (uncolored ink), the second printing control unit refers to the same color conversion table as is used by a first printing control unit. Thereby the second printing control unit color-converts input image data into image data comprising gradation data corresponding to at least the amounts of colored inks in C, M, Y, R, V, and K consumed. The second printing control unit can carry out such control as to cause a printer (printing device) to use only the C, M, Y, R, V, and K colored ink and print a print image, using the image data.

Abstract: A method of producing a color conversion table capable of enhancing continuity in an image-data color conversion, an image processing device and a method using the color conversion table, a program and a recording medium. The image processing device performs an image processing by using a color conversion table produced by using functions for evaluating a smoothing level at each element of lattice point data after color conversion by a color conversion table. Functions for evaluating the above smoothing level include a function based on the twisted quantity of ink-quantity vector, a function based on a twisted quantity at a virtual CMY, a function based on a deviation from a target ink quantity, a function based on a deviation from a target virtual CMY, a function based on a failure to meet an ink quantity limitation, a function based on ink quantity reduced to minus, and a function based on ink generation.

Abstract: In one example, there is designed a system for calculating an evaluation index for sample ink amount data from a color difference evaluation index and an image quality evaluation index, and creating a profile based on a highly rated sample. In this system, the printer driver is designed to use different indexes to create plural profiles, and to perform color conversion using these plural profiles. These plural profiles may be selected appropriately according to user needs, printing conditions, type of image targeted for printing, and the like.

Abstract: A spectral printing model converter is used to convert ink amount data to spectral reflectance of a color patch to be printed according to the ink amount data. A plurality of sample ink amount data each representing a set of ink amounts of plural inks is provided, and each sample ink amount data is converted into spectral reflectance of a virtual sample patch to be printed with the ink amounts represented by the sample ink amount data using the spectral printing model converter. An evaluation index is calculated for each sample ink amount data, where the evaluation index includes a color difference index and an image quality index of the virtual sample patch to be printed according to the sample ink amount data. The color difference index represents a color difference between a sample color which is calculated from the spectral reflectance and a comparative color which is selected as a basis for comparison.

Abstract: The invention employs at least three chromatic colored inks as well as a chromatic colored ink that has a lower spectral reflectance at each wavelength region in which the spectral reflectance of these three colored inks is greater. The chromatic colored ink is added to the at least three colors to enable printing with minimal differences between colors seen under a certain standard light source and the same colors seen under another light source. It is thus possible to ensure printing with fewer changes in color as a result of changes in light source, such as the ability to produce colors having a generally constant spectral reflectance across all wavelengths by combining inks.

Abstract: When colored inks and a clear ink are recorded, the printing medium tends to undulate and blotting of ink can occur. Thus, it is difficult to obtain favorable picture quality under various printing conditions. To cope with this, a printing device is designed so that colored inks and a clear ink are recorded on a printing medium and an image thereby formed is controlled. The maximum recording rate for the colored inks is made lower than the maximum ink recording rate at which ink can be recorded per unit area of a printing medium. The quantities of inks are determined so that the clear ink and the colored inks are recorded on the printing medium with the maximum ink recording rate at which ink can be recorded per unit area of the printing medium taken as the limit. The image is formed with the thus determined ink quantities.

Abstract: Lattice points for correspondence defining data are determined by transmitting from a client to a server the original correspondence defining data which previously prescribes correspondence between the lattice points in the low-dimensional color space and the lattice points for ink amount for a printing apparatus, causing the server to acquire correspondence between lattice points in the low-dimensional color space and lattice points in the device-independent color space by referencing the original correspondence defining data, prescribing a smoothness evaluation function which evaluates smoothness of the arrangement of lattice points in the device-independent color space and has as a variable the information about the position of lattice points in the low-dimensional color space, and optimizing the arrangement of lattice points in the device-independent color-space by improving the rating of the smoothness evaluation function, with the information about the position of lattice points varied.

Abstract: A method for determining lattice points to be referenced to prepare the correspondence defining data, said method including steps of prescribing a smoothness evaluation function which evaluates smoothness of arrangement of lattice points in the device-independent color space and contains a constraint condition that the arrangement of lattice points becomes nonuniform at a certain position in the device-independent color space and which has as a variable the lattice point position information in the low-dimensional color space which is prescribed by less color components than the number of inks used by the printing apparatus, optimizing the arrangement of lattice points in the device-independent color space by improving the rating of the smoothness evaluation function, with the lattice point position information in the low-dimensional color space varied, and determining lattice points to be referenced to prepare the correspondence defining data in the optimized state.

Abstract: A method for determining lattice points to be referenced to prepare the correspondence defining data, said method including steps of prescribing a smoothness evaluation function which evaluates smoothness of arrangement of lattice points in the device-independent color space and which has as a variable the lattice point position information in the low-dimensional color space which is prescribed by less color components than the number of inks used by the printing apparatus, optimizing the arrangement of lattice points in the device-independent color-space by improving the rating of the smoothness evaluation function, with the lattice point position information in the low-dimensional color space varied, and associating the amount of each ink with the lattice points in the low-dimensional color space in the optimized state.

Abstract: A method for determining lattice points to be referenced to prepare the correspondence defining data, said method including steps of prescribing a smoothness evaluation function which has a function form differing depending on each region in the color gamut to which the lattice point to be evaluated belongs and also contains a constraint condition that the closer the lattice point is to the boundary of the region of the color gamut, the more the evaluated value decreases as the result of its movement, optimizing the arrangement of lattice points in the device-independent color space by improving the rating of the smoothness evaluation function, with the lattice point position information in the low-dimensional color space varied, and determining lattice points to be referenced to prepare the correspondence defining data in the optimized state.

Abstract: It used to be difficult to determine representative colors which allow color conversion with accuracy throughout color spaces without occurrences of local tone jump.