Abstract: Techniques described herein convert a plurality of digital images into an image or images more amenable to data compression. In one embodiment, an ordered collection of input digital images is provided. A first digital image from the ordered collection is identified as a base image, and an empty image strip is formed. For each second digital image from the ordered collection, and upon a condition in which the second image is the base image, the base image is appended to the image strip. Upon a condition in which the second image is not the base image, a difference image is computed from the base image and the second image and appended to the difference image to the image strip. Quantization and conventional image compression may be applied to the image strip to produce a compressed image strip.

Abstract: Techniques described herein convert digital images into images suitable for use as coloring book pages and the like. The techniques include applying a smoothing operator to at least one channel image of a digital input image to form at least one smoothed image. A scaling operator is then applied to the at least one smoothed image to form at least one scaled image. A tone equalization operator is then applied to the at least one scaled image to form at least one equalized image. An edge detection operator is then applied to the at least one scaled image to form at least one edge image. In addition, a threshold operator is applied to the at least one edge image to form at least one threshold image. A digital line drawing is then created based at least in part on the at least one threshold image.

Abstract: Techniques described herein convert a plurality of digital images into an image or images more amenable to data compression. In one embodiment, an ordered collection of input digital images is provided. A first digital image from the ordered collection is identified as a base image, and an empty image strip is formed. For each second digital image from the ordered collection, and upon a condition in which the second image is the base image, the base image is appended to the image strip. Upon a condition in which the second image is not the base image, a difference image is computed from the base image and the second image and appended to the difference image to the image strip. Quantization and conventional image compression may be applied to the image strip to produce a compressed image strip.

Abstract: Techniques described herein convert digital images into images suitable for use as coloring book pages and the like. The techniques include applying a smoothing operator to at least one channel image of a digital input image to form at least one smoothed image. A scaling operator is then applied to the at least one smoothed image to form at least one scaled image. A tone equalization operator is then applied to the at least one scaled image to form at least one equalized image. An edge detection operator is then applied to the at least one scaled image to form at least one edge image. In addition, a threshold operator is applied to the at least one edge image to form at least one threshold image. A digital line drawing is then created based at least in part on the at least one threshold image.

Abstract: A method for adjusting a color in a color space comprises adjusting the color along a gradient path to a point in or on a color gamut. The gradient path is determined from a potential field derived from the color gamut consisting of gamut points in the color space. The potential field can be derived from one or more points in the color gamut and different functions may be used to determine the potentials due to different points in the gamut. The potential at a point in the color space due to the gamut point can be a function, including an inverse power, of distance of the point in the color space from the gamut point. The gradient path can be determined from the gradient of the potential field by quadric error-based surface simplification of a surface mesh representing a surface of the gamut.

Abstract: An improved relief printing plate and method for producing said plate is disclosed. Substantially all sizes of relief features resolve a fixed pattern which improves print quality. The pattern is applied to image areas in halftone data used to produce an image mask that is subsequently used to convert a plate precursor into a relief plate. The accuracy, ink density and tonal response of printed images corresponding to relief features that include the pattern are comparable or better than relief features produced without the pattern.

Abstract: A method for adjusting a color in a color space comprises adjusting the color along a gradient path to a point in or on a color gamut. The gradient path is determined from a potential field derived from the color gamut consisting of gamut points in the color space. The potential field can be derived from one or more points in the color gamut and different functions may be used to determine the potentials due to different points in the gamut. The potential at a point in the color space due to the gamut point can be a function, including an inverse power, of distance of the point in the color space from the gamut point. The gradient path can be determined from the gradient of the potential field by quadric error-based surface simplification of a surface mesh representing a surface of the gamut.

Abstract: A method for adjusting a color in a color space comprises adjusting the color along a gradient path to a point in or on a color gamut. The gradient path is determined from a potential field derived from the color gamut consisting of gamut points in the color space. The potential field can be derived from one or more points in the color gamut and different functions may be used to determine the potentials due to different points in the gamut. The potential at a point in the color space due to the gamut point can be a function, including an inverse power, of distance of the point in the color space from the gamut point. The gradient path can be determined from the gradient of the potential field by quadric error-based surface simplification of a surface mesh representing a surface of the gamut.

Abstract: Modification of color values in a page description file can be carried out by converting implicit color commands within the page description file to explicit color commands. The color values specified by the explicit color commands within the page description file then are adjusted to calibrate an output device for enhanced color fidelity. Implicit color commands specify color values indirectly, for example, by defining color as a function of other graphic information and color reference values. Consequently, color modification prior to RIP conversion generally is difficult. Conversion and modification of explicit color values provides a higher degree of color conversion accuracy without the need for RIP conversion of the page description file.

Abstract: An improved relief printing plate and method for producing said plate is disclosed. Substantially all sizes of relief features resolve a fixed pattern which improves print quality. The pattern is applied to image areas in halftone data used to produce an image mask that is subsequently used to convert a plate precursor into a relief plate. The accuracy, ink density and tonal response of printed images corresponding to relief features that include the pattern are comparable or better than relief features produced without the pattern.

Abstract: A method for adjusting a color in a color space comprises adjusting the color along a gradient path to a point in or on a color gamut. The gradient path is determined from a potential field derived from the color gamut consisting of gamut points in the color space. The potential field can be derived from one or more points in the color gamut and different functions may be used to determine the potentials due to different points in the gamut. The potential at a point in the color space due to the gamut point can be a function, including an inverse power, of distance of the point in the color space from the gamut point. The gradient path can be determined from the gradient of the potential field by quadric error-based surface simplification of a surface mesh representing a surface of the gamut.

Abstract: A color imaging technique includes setting a target value in a device-independent first color space and mapping the target value to a substantially complete point set in a second color space. The point set may include a plurality of points, each of which define substantially the same calorimetric value via a unique combination of colorants. After mapping the target value to a substantially complete point set, a point may be chosen. Moreover, after choosing a point in the point set, device-dependent colorant values defined by the point may be determined. In this manner, the invention may provide control over the colorants that are used to image a particular color.

Abstract: A method for converting CMYK source device values to CMYK destination device values includes converting the CMYK source device values to a four-color device-independent color space using a source profile with a four-color device-independent color space. The four color device-independent color space is converted to the CMYK destination values using a destination profile with the four color device-independent color space, and three colors of the four color device-independent color space are used to define the color of a combined CMYK values and the remaining device-independent color space color is used to define the color of only a K colorant.

Abstract: A method of performing color conversion between profiles includes comparing two sets of measured and reference data for at least one device corresponding to one of the profiles used in the color conversion, the data from the two sets of measured and reference data correspond to the same device values and are indicative of differences in behavior between a current state of the device and a reference state of the device in which at least one member of the set includes more than one non-zero value of colorants. And performing one-dimensional corrections to one of the profiles in order to account for the differences between the measured and reference data sets prior to performing color conversion.

Abstract: A color mapping method is used in transforming colors between color imaging systems. The method includes using forward transformation profiles that characterize the color imaging systems to generate respective sets of device-independent color values for the color imaging systems. Color conversions are calculated by recursively reducing differences between the respective sets of device-independent color values. Based on these color conversions, a color map is constructed that describes a relationship between the color imaging systems.

Abstract: Techniques are described for preparing halftone bitmap images for printing on inkjet printers. The techniques may involve exclusive use of low-density inks to reproduce highlight colors and means for reducing the amount of ink applied to the page within “solid” areas while maintaining complete coverage of these areas. The techniques may rely on the high addressability and larger ink palette of recent inkjet printers. For example, some inkjet printers offer seven ink channels: low and high density inks for the cyan, magenta, and black channels, and a single high-density yellow ink. In one embodiment, halftone dots within a bitmap image are separated into perimeter data and core data. The perimeter data is then associated with a low-density ink channel and the core data is associated with a high-density ink channel.

Abstract: A color imaging technique includes setting a target value in a device-independent first color space and mapping the target value to a substantially complete point set in a second color space. The point set may include a plurality of points, each of which define substantially the same colorimetric value via a unique combination of colorants. After mapping the target value to a substantially complete point set, a point may be chosen. Moreover, after choosing a point in the point set, device-dependent colorant values defined by the point may be determined. In this manner, the invention may provide control over the colorants that are used to image a particular color.

Abstract: A method of characterizing a color imaging system is provided. The method comprises obtaining first data indicative of output of the color imaging system. The first data is processed, to yield second data, according to a color appearance model that varies in accordance with neutrality of colors indicated by the first data. Other methods are provided as well as systems and computer program products for characterizing color imaging systems and devices and for producing colors.

Abstract: A system and method for multi-dimensional color transformation apply constraints to the transformation function to preserve the presence or absence of particular color information while achieving high accuracy color match. With a constrained multi-dimensional color transformation (CMT), a destination device, such as a color proofer, can provide an accurate color match relative to a source or “target” device, such as a printing press, and preserve dot integrity. In particular, the constraints can preserve selected color information that is present in an image produced by the source device, and prevent addition of other selected color information that would not be present in the source device image. In a halftone imaging device, the constraints prevent the removal or addition of dots from and to the image produced by destination device.

Abstract: A color mapping method is used in transforming colors between color imaging systems. The method includes using forward transformation profiles that characterize the color imaging systems to generate respective sets of device-independent color values for the color imaging systems. Color conversions are calculated by reducing differences between the respective sets of device-independent color values. Based on these color conversions, a color map is constructed that describes a relationship between the color imaging systems.