Display data processing device, image display system, and display data processing method

A display data processing method for performing color adjustment on gradation values of pixels of a frame image of an input video signal and outputting the adjusted gradation value to a display device, the method comprising:

• a first gamma correction process of setting, by a first gamma correction unit, based on first composite correction information according to a first gamma characteristic indicating a correspondence relationship between a first input gradation value and a first normalized brightness value and a first power function indicating a correspondence relationship between the first normalized brightness value and a first corrected gradation value, the gradation value as the first input gradation value and converting the first input gradation value into the first corrected gradation value;
• a video gain correction process of a video gain correction unit performing color adjustment on the first corrected gradation value according to video gain correction by a video gain correction unit and outputting the adjusted gradation value as a video gain corrected gradation value;
• and
• a second gamma correction process of setting, by a second gamma correction unit, based on second composite correction information according to a second power function having the same power as the first power function, which indicates a correspondence relationship between a second input gradation value and a second normalized brightness value, and a second gamma characteristic indicating a correspondence relationship between the second normalized brightness value and a second corrected gradation value, the video gradation value as the second input gradation value and converting the second input gradation value into the second corrected gradation value.