Display device and method for expanding color space

A display device provided with a display panel for displaying an image, the display device comprising:

• a processor;
• an expanded video signal generation circuit configured to perform an expansion process for increasing a signal value of an input video signal, and output data obtained by the expansion process as an expanded video signal;
• an expansion coefficient decision circuit configured to decide an expansion coefficient to be used for the expansion process by the expanded video signal generation circuit;
• and
• an output video signal generation circuit configured to generate an output video signal to be outputted to the display panel based on the expanded video signal, wherein
• the expansion coefficient decision circuit decides an inverse of saturation, obtained based on the input video signal, as an expansion coefficient for each pixel,
• the expanded video signal generation circuit multiplies the expansion coefficient, decided by the expansion coefficient decision circuit, by a signal value of the input video signal for each pixel, to generate the expanded video signal, and
• when a pixel to be processed for obtaining the expansion coefficient is defined as a target pixel, the expansion coefficient decision circuit decides an expansion coefficient to be used for the expansion process on an input video signal of the target pixel based on input video signals of a plurality of pixels included in a predetermined range centered on the target pixel.