The disclosure relates to a color gamut mapping device that allows a gamma characteristic for each color to be tuned to match a target gamma curve through color gamut mapping, a tuning method thereof, and an image processor including the same. The color gamut mapping device controls a hue and saturation of an image signal to match a target color gamut using a hue parameter assigned to each of a plurality of hue axes and a saturation parameter assigned to correspond to each of a plurality of saturation control areas of each hue axis, and the color gamut mapping device changes the saturation of the image signal by changing the saturation parameter which is assigned to each hue axis and corresponds to the uppermost saturation control area so that a gamma characteristic for each color of the image signal is changed to match a target gamma curve for each color.

The disclosure relates to a color gamut mapping device that allows a gamma characteristic for each color to be tuned to match a target gamma curve through color gamut mapping, a tuning method thereof, and an image processor including the same. The color gamut mapping device controls a hue and saturation of an image signal to match a target color gamut using a hue parameter assigned to each of a plurality of hue axes and a saturation parameter assigned to correspond to each of a plurality of saturation control areas of each hue axis, and the color gamut mapping device changes the saturation of the image signal by changing the saturation parameter which is assigned to each hue axis and corresponds to the uppermost saturation control area so that a gamma characteristic for each color of the image signal is changed to match a target gamma curve for each color.

Tone mapping is performed by digital image processing circuitry on a macro-pixel basis. A luminance value of a macro-pixel of a digital image in a color space is determined. The macro-pixel includes a plurality of individual pixels. Respective tone-mapping gain values of each pixel of the macro-pixel are determined based on the determined luminance value of the macro-pixel. The determined tone-mapping gains are applied to the respective pixels of the macro-pixel. The color space may be a CFA color space, such as a Bayer color space.

A non-transitory machine readable medium that has a computer program for adjusting color values of an image represented in a color space is described. The image includes a set of pixels. Each pixel includes a set of color values. The computer program displays a composite bump on a tonal adjustment graph that is defined along a particular color component of the color space. The composite bump is generated by blending several bumps on the tonal adjustment graph. In response to receiving an input on a location on the tonal adjustment graph, the computer program creates a new bump based on the input and blending the new bump with the composite bump to create a modified composite bump. The computer program adjusts the color values of the image based on the modified composite bump.

A non-transitory machine readable medium that has a computer program for adjusting color values of an image represented in a color space is described. The image includes a set of pixels. Each pixel includes a set of color values. The computer program displays a composite bump on a tonal adjustment graph that is defined along a particular color component of the color space. The composite bump is generated by blending several bumps on the tonal adjustment graph. In response to receiving an input on a location on the tonal adjustment graph, the computer program creates a new bump based on the input and blending the new bump with the composite bump to create a modified composite bump. The computer program adjusts the color values of the image based on the modified composite bump.

Flare compensation includes receiving a first image and a second image; converting the first and the second images from an RGB domain to a YUV domain; obtaining an intensity differences profile along a stitch line between the first and the second images, where the intensity differences profile is obtained for the Y component; obtaining a dark corner intensity differences profile between the first and the second images based on a relative illumination of an area outside a first image circle of the first image and a second image circle of the second image, where the dark corner intensity differences profile is obtained for the Y component; obtaining a flare profile using the intensity differences profile and the dark corner intensity differences profile; converting the flare profile of the Y component to an RGB flare profile; and modifying one of the first or second images based on the RGB flare profile.

Flare compensation includes receiving a first image and a second image; converting the first and the second images from an RGB domain to a YUV domain; obtaining an intensity differences profile along a stitch line between the first and the second images, where the intensity differences profile is obtained for the Y component; obtaining a dark corner intensity differences profile between the first and the second images based on a relative illumination of an area outside a first image circle of the first image and a second image circle of the second image, where the dark corner intensity differences profile is obtained for the Y component; obtaining a flare profile using the intensity differences profile and the dark corner intensity differences profile; converting the flare profile of the Y component to an RGB flare profile; and modifying one of the first or second images based on the RGB flare profile.

Compared to traditional gamma-coded video, perceptually quantized video provides greater flexibility for the transmission and display management of high-dynamic range video, but it does not compresses as efficiently using existing standard codecs. Techniques are described to improve the coding efficiency of perceptually coded video by applying a color cross-talk transformation after the RGB/XYZ to LMS transformation. Such a transform increases luma and chroma correlation for color appearance models, but improves perceptual uniformity and overall coding efficiency for wide color gamut, HDR, signals.

Compared to traditional gamma-coded video, perceptually quantized video provides greater flexibility for the transmission and display management of high-dynamic range video, but it does not compresses as efficiently using existing standard codecs. Techniques are described to improve the coding efficiency of perceptually coded video by applying a color cross-talk transformation after the RGB/XYZ to LMS transformation. Such a transform increases luma and chroma correlation for color appearance models, but improves perceptual uniformity and overall coding efficiency for wide color gamut, HDR, signals.

Disclosed is a color gamut matching method. The method includes: obtaining image data to be matched of a source terminal; establishing a preliminary matching relationship between the image data to be matched and image data to be output of a display terminal according to color gamut data coordinates of the source terminal and color gamut data coordinates of the display terminal; obtaining preliminary image data to be output of the display terminal according to the preliminary matching relationship; and accurately matching the preliminary image data to be output of the display terminal according to a 3D look-up table to obtain accurate image data to be displayed of the display terminal. Further disclosed are a color gamut matching device, a display terminal and a readable storage medium. The present disclosure can solve the color distortion of the display color gamut and improve the display effect of the display.