Patent ID: 8165391

Claim:
An image processing apparatus comprising: a processor which is programmed to control: an input unit adapted to input an image formed by attribute regions which are a non-background region and a background region including pixels each having a preset luminance value and color difference value; a read unit adapted to sequentially read a luminance value and color difference value of each pixel forming the image; a determination unit adapted to determine, based on a luminance value and color difference value of a pixel of interest read by the read unit, whether the pixel of interest belongs to the background region or the non-background region; a recording unit adapted to record the luminance value and color difference value of the pixel of interest as data of a group different from that to which a preceding pixel read by the read unit immediately before the pixel of interest belongs if an attribute region to which the pixel of interest belongs is different from that to which the preceding pixel belongs, and record the luminance value of the pixel of interest adjacent to data already recorded in the group to which the preceding pixel belongs if the attribute region to which the pixel of interest belongs is the same as that to which the preceding pixel belongs; and an output unit adapted to output the data recorded by the recording unit.