Patent attributes
An image forming apparatus and method for performing appropriate attribute determination on a wide area of image data with a simple configuration of the apparatus and performing high-quality image forming are provided. A luminance signal of each pixel of a multi-valued image is inputted to the original document reading unit, and a color attribute of a pixel of interest is determined by the pixel attribute determination unit based on the luminance signal. In the main controller, the array attribute number determined in accordance with an array of the color attribute is counted with respect to 32 lines of a block, which is obtained by dividing a band having 64 lines of the multi-valued image into 8 blocks in the main scanning direction, and the determined color attribute is counted. Based on the counted value, a parameter indicative of an image characteristic of the block is calculated. Based on the counted value and the calculated parameter, an image attribute of the block is determined. Based on the determination result, an image attribute of the band is determined.
