Patent ID: 8503025

Claim:
An image processing apparatus comprising: a processor; a color information generating unit that generates information of color values included in input image data; an Index table generating unit that generates an Index table in which a first identification information according to a hash value is associated with a first predetermined number of color values among the color values; a drawing unit that generates a second identification information according to the hash value for each color value included in the input image data and performs, when the second identification information is different from the first identification information associated with a color value included in the Index table having a same value as the color value, drawing according to the color value, and when the second identification information is the same as the first identification information, drawing according to the first identification information; and a converting unit that converts an image drawn by the identification information into a color value corresponding to the identification information; wherein the Index table generating unit further generates header information identifying which drawing of drawing according to the identification information and drawing according to the color value is performed for each pixel included in an image according to the input image data, the drawing unit generates first-format pixel data including the header information and the identification information by performing drawing according to the identification information and generates second-format pixel data including the header information and the color value by performing drawing according to the color value, and the image processing apparatus further includes a storage unit that stores image data including two pixel formats of the first format and the second format in one area.