An image processing apparatus includes a first image processing unit having a fixed image processing function to perform image processing of image data. A second image processing unit has a fixed image processing function to perform image processing of image area data. A reconfigurable image processing unit is capable of having selectively, by reconfiguration of an architecture of the reconfigurable image processing unit, one of least a first image processing function for image processing of image data and a second image processing function for image processing of image area data. A control unite reconfigures the architecture of the reconfigurable image processing unit to have one of at least the first image processing function and a second image processing function on a basis of whether the image processing apparatus processes a color image or a monochrome image.