Display control device, image display device, display control method, and recording medium to control a light emission amount of a region based on a light source control value for the region

A display control device of an image display device that includes a display panel having a plurality of pixel positions and configured to display an image by changing a transmittance at each pixel position and a backlight including a plurality of regions, and generates and outputs an output image signal by performing color conversion and luminance conversion on an input image signal while sequentially taking, as a pixel of interest, a plurality of pixels constituting an image represented by the input image signal, the display control device comprising:

• processing circuitry
• to calculate, from the input image signal, a feature amount for each of the plurality of regions;
• to calculate, from the feature amount for each of the plurality of regions, a light source control value for each of the plurality of regions;
• to generate, for each of the regions, color shift information for the region on a basis of the light source control value for the region;
• to acquire, from the input image signal, pixel position information for the pixel of interest;
• to generate luminance conversion information for the pixel of interest, with a region to which the pixel of interest belongs and regions therearound as a plurality of reference regions, from the light source control value for each of the plurality of reference regions, and the pixel position information for the pixel of interest, and generate color conversion information for the pixel of interest from the color shift information for each of the plurality of reference regions and the pixel position information for the pixel of interest;
• and
• to convert, on a basis of the color conversion information and the luminance conversion information for the pixel of interest, a color and a luminance of the input image signal for the pixel of interest to generate the output image signal for the pixel of interest,
• wherein for each of the plurality of regions, the color shift information indicates a ratio, or its reciprocal, of a change in an intensity of color of illumination light from the region to a change in the light source control value for the region, and
• the color conversion information indicates a color conversion value, and
• the processing circuitry multiplies a color component of the input image signal by the color conversion value or its reciprocal to generate a color component of the output image signal, and
• wherein the display control device
• controls, for each of the plurality of regions, a light emission amount of the region on a basis of the light source control value for the region, and
• controls a transmittance at a position of the pixel of interest of the display panel by using the output image signal for the pixel of interest.