Abstract:
A method for providing a user access to an extended color gamut digital image and for obtaining payment therefor, comprising the steps of representing the extended color gamut digital image with a limited color gamut digital image and one or more associated residual image(s) representing a difference between the extended color gamut digital image and the limited color gamut digital image; storing the limited color gamut digital image and the associated residual images(s) in an electronic memory; providing the user or user's designee access to the limited color gamut digital image in the electronic memory to provide a preview image; obtaining a payment identifier from the user and making payment using such payment identifier to permit the user or user's designee access to the associated residual image(s); and providing the user or user's designee access to the associated residual image(s) in the electronic memory.
Abstract:
A method of generating a reduced color gamut boundary for a color output device using three or more colorants, wherein the amount of each colorant is controlled by a colorant control signal vector, including determining a forward device model for the color output device relating the colorant control signal vector to the corresponding output color; determining a complete color gamut boundary for the color output device, comprising a set of color gamut boundary points; and determining a set of candidate colorant control signal vectors for each point in the complete color gamut boundary. The method also includes selecting a preferred colorant control signal vector.
Abstract:
A method for representing a digital image having color values with an extended color gamut in a storage color space having a limited color gamut comprising the steps of: adjusting the color values of the extended color gamut digital image to fit within the limited color gamut to form a limited color gamut digital image; representing the limited color gamut digital image in the storage color space; determining a clipped limited color gamut digital image in which highly quantized regions in the limited color gamut digital image have been clipped; determining a residual image representing a difference between the extended color gamut digital image and the clipped limited color gamut digital image; and associating the residual image with the limited color gamut digital image in the storage color space such that the associated residual image and the limited color gamut digital image in the storage color space are adapted to be used to form a reconstructed extended color gamut digital image.
Abstract:
A method for correcting the color balance of an input digital color image in an input color space captured under a capture illuminant to produce a balanced digital color image includes transforming the input digital color image to a balancing color space, wherein the balancing color space has three color channels corresponding to three color space primaries, the color space primaries being chosen so that minimal color errors can be produced when correcting the color balance for a set of one or more capture illuminants relative to aim colors that would be produced if the digital color image were captured under reference conditions; and correcting the color balance of the input digital color image in the balancing color space to produce a balanced digital color image having minimal color errors relative to aim colors that would be produced if the digital color image were captured under reference conditions.
Abstract:
A method of selecting a preferred colorant control signal vector for a color output device for reproducing a desired output color, the color output device producing output colors using four or more colorants, wherein the amount of each colorant is controlled by the colorant control signal vector, includes determining a device model for the color output device relating the colorant control signal vector to the corresponding output color; using the device model to determine a set of valid colorant control signal vectors whose corresponding output color substantially matches the desired output color; and selecting the preferred colorant control signal vector from the set of valid colorant control signal vectors using a cost function responsive to one or more cost attribute(s) that vary as a function of the colorant control signal vector.
Abstract:
A method for determining information parameter(s) useful in processing a digital image having color values with an extended color gamut, includes the steps of: adjusting the color values of the extended color gamut digital image to fit within a limited color gamut to form a limited color gamut digital image; determining a residual image representing a difference between the extended color gamut digital image and the limited color gamut digital image; and analyzing the residual image to determine one or more image information parameter(s) related to the information contained in the residual image such parameter(s) being useful in processing the digital image.
Abstract:
A method for multi-toning an input digital image having input pixels with two or more color channels to form an output digital image having modified output levels. The method includes determining modified output levels using a combined error signal formed from intermediate error signals for each color channel together with an error signal offset value, and adjusting the input levels for the nearby pixels responsive to weighted error signals.
Abstract:
A method for determining a sharpness predictor for an input digital image includes determining one or more image metrics by analyzing the input digital image; and determining the sharpness predictor from the one or more image metrics.
Abstract:
A method for printing an input digital image using a digital printer having a set of colorants with substantially the same color but different densities, including a sequence of node points where each of the two or more colorants are either at their maximum or minimum values, setting colorant concentrations such that the color channel output responses corresponding to the sequence of node points are substantially equally spaced in a visually uniform color space; forming colorant control look-up tables to provide smooth transitions in the color channel output response between the sequence of node points; addressing the colorant control look-up tables with the printer code value for each pixel of the input digital image to determine the colorant control signals for each of the two or more colorants; and controlling the digital printer using the colorant control signals to produce a print of the input digital image.
Abstract:
A method for determining colorant control values for a color imaging device having four or more colorants is disclosed. The method includes defining a color mapping for a set of paths through a three-channel color space, defining a color mapping function for the three-channel color space relating the three-channel color space values to colorant control values for the four or more colorants of the color imaging device by interpolating between the color mapping defined for the set of paths, forming a forward three-channel color model relating the three-channel color space values to device-independent color values, inverting the forward three-channel color model to determine an inverse three-channel color model relating the device-independent color values to the three-channel color space values, and combining the inverse three-channel color model and the color mapping function to determine an inverse device color model.