Image processing apparatus, image forming apparatus, image processing method, and computer readable medium storing program

摘要

An image processing apparatus includes: a coefficient calculation unit that calculates a coefficient for converting image data having a predetermined number of pixels to image data having a smaller number of pixels than the predetermined number of pixels, including a coefficient multiplied by an integer power of 2, as a conversion coefficient; a calculation unit that multiplies each pixel value of image data prior to image reduction processing by the conversion coefficient previously calculated by the coefficient calculation unit thereby to calculate each pixel value of the image data subjected to the image reduction processing; and a shift unit that shifts each of the pixel values calculated by the calculation unit by a number of bits to counteract the integer power of 2-multiplied coefficient included in the conversion coefficient.