IMAGE PROCESSING APPARATUS AND METHOD

摘要

An image processing apparatus includes an amplifying unit for, during a main scanning line period, amplifying an analog image signal input from a photoelectric conversion element and outputting the signal; an A/D converting unit for analog/digital- converting the signal to digital image data and outputting the data; and a digital offset correcting unit for performing a low-pass filter calculation based on the data to obtain an average value, calculating, based on the average value, a digital correction value used for correcting the data to obtain a desired black offset level, and performing correction on the data using the value. The digital offset correcting unit compares the value to a threshold, reduces the value to be equal to or less than the threshold if the value is equal to or greater than the threshold and updates the value to the reduced value, and performs the low-pass filter calculation and calculates the value.