An image display apparatus includes: an image signal processing unit which
adjusts an input grayscale values included in an input image signal
according to a predetermined grayscale characteristic; a display unit
which displays an image based on an image signal included in an output
grayscale value adjusted by the image signal processing unit; and a
grayscale characteristic changing unit which changes a correlation
between the input and output grayscale values defined based on the
grayscale characteristic.