The present principles relate to a method and device for gamut mapping from a first color gamut towards a second color gamut. The method comprises, in a plane of constant hue, obtaining a target lightness for a color on the boundary of first gamut with maximum chroma, called first cusp color; and lightness mapping of the color from the first color gamut towards the second color gamut wherein the lightness mapped color is calculated from a parabolic function applied to the color, the parabolic function mapping the first cusp color to a color having the target lightness. According to a particular characteristic, a preserved chroma is also obtained; and in case the chroma of the color is lower than or equal to the preserved chroma, the lightness mapped color is the color, and in case the chroma of the color is higher than the preserved chroma, the lightness mapped color is calculated from the parabolic function applied to the color.

The present principles relate to a method and device for gamut mapping from a first color gamut towards a second color gamut. The method comprises, in a plane of constant hue, obtaining a target lightness for a color on the boundary of first gamut with maximum chroma, called first cusp color; and lightness mapping of the color from the first color gamut towards the second color gamut wherein the lightness mapped color is calculated from a parabolic function applied to the color, the parabolic function mapping the first cusp color to a color having the target lightness. According to a particular characteristic, a preserved chroma is also obtained; and in case the chroma of the color is lower than or equal to the preserved chroma, the lightness mapped color is the color, and in case the chroma of the color is higher than the preserved chroma, the lightness mapped color is calculated from the parabolic function applied to the color.

Disclosed is an apparatus and method for combating light sensitivity, or photophobia, for people with low vision. Both the apparatus and method filter particular wavelengths of light associated with photophobia. This filtering is achieved while maintaining a luminance that is acceptable to the user and that maintains contrast. The apparatus of the disclosure is a mechanical filter that can be applied over an electronic screen. The method utilizes software and a filtering module associated with either the CPU or GPU of a computer. The filtering module processes a video signal by eliminating certain targeted wavelengths of light.

A technique for image processing, comprising: receiving input image data, wherein the image data is companded into a first bit depth, wherein the image data includes incomplete color values for pixels of the image data, and wherein the image data is associated with a first color space, interpolating the image data to generate color values for the incomplete color values for pixels of the image data, expanding the image data from the first bit depth to a second bit depth, wherein the color values of the expanded image data have a linear dynamic range, and wherein the second bit depth is higher than the first bit depth, converting the color values for pixels of the expanded image data from the first color space to a second color space, and compressing the color values for pixels of the image data to a third bit depth, the third bit depth lower than the second bit depth, and wherein the compressed color values have a nonlinear dynamic range.

A technique for image processing, comprising: receiving input image data, wherein the image data is companded into a first bit depth, wherein the image data includes incomplete color values for pixels of the image data, and wherein the image data is associated with a first color space, interpolating the image data to generate color values for the incomplete color values for pixels of the image data, expanding the image data from the first bit depth to a second bit depth, wherein the color values of the expanded image data have a linear dynamic range, and wherein the second bit depth is higher than the first bit depth, converting the color values for pixels of the expanded image data from the first color space to a second color space, and compressing the color values for pixels of the image data to a third bit depth, the third bit depth lower than the second bit depth, and wherein the compressed color values have a nonlinear dynamic range.

A code reader includes a color imager and a processor operably coupled to the color imager. The processor is configured to: set an RGB imager pixel color gain; capture at least one image with active or ambient illumination using the color imager with a calibration target in view; calculate a mean value of R, G, B pixels for the at least one image; use a color plane as a reference, determining a color gain to set calibration parameters; capture at least one additional image using the calibration parameters; and save the calibration parameters if mean values of the R, G, B, pixels for the at least one additional image are within a predetermined range to be used by the camera for subsequent image capture, and apply to each pixel of the image a corresponding color correction matrix from among a plurality of stored color correction matrices.

A code reader includes a color imager and a processor operably coupled to the color imager. The processor is configured to: set an RGB imager pixel color gain; capture at least one image with active or ambient illumination using the color imager with a calibration target in view; calculate a mean value of R, G, B pixels for the at least one image; use a color plane as a reference, determining a color gain to set calibration parameters; capture at least one additional image using the calibration parameters; and save the calibration parameters if mean values of the R, G, B, pixels for the at least one additional image are within a predetermined range to be used by the camera for subsequent image capture, and apply to each pixel of the image a corresponding color correction matrix from among a plurality of stored color correction matrices.

An apparatus configured to correct a captured image using a gloss component based on a virtual light source sets a light-source color of the virtual light source. The apparatus generates the gloss component on a subject in the captured image using the light-source color corrected according to a color tone of the captured image. The apparatus corrects the captured image by adding the generated gloss component to the captured image.

An apparatus configured to correct a captured image using a gloss component based on a virtual light source sets a light-source color of the virtual light source. The apparatus generates the gloss component on a subject in the captured image using the light-source color corrected according to a color tone of the captured image. The apparatus corrects the captured image by adding the generated gloss component to the captured image.

Based on a histogram of saturation of an input video, a saturation conversion function is determined, and, referring to the determined saturation conversion function, the saturation of each pixel of the input video is converted. Alternatively, a saturation conversion coefficient determination function is generated from the histogram, a saturation conversion coefficient is determined from the saturation conversion coefficient determination function and the saturation, and color differences are multiplied by the determined saturation conversion coefficient. Regardless of what saturation distribution the input video has, the saturation can be properly enhanced, and at the same time a high gradation expression can be obtained.