Study Of Image Calibration Technology Based On Scanner Controller GL847

Scanner is mainly consist of optical imaging part, transimission machinery partsand transform circuit components, which cooperate each other and convert opticalsignals reflecting image characteristics to acceptable signals by computer. Photoelectricconversion parts are the core of the scanner. Most scanners use charge-coupled devicecalled CCD, which can convert the optical to the corresponding electric signals.However, because of the dark current in CCD, quantum effects, material structureof local difference and various noise, each pixel doesn’t produce the same gray value forsame irradiance. Therefore, in order to reflect the color information accurately in highquality image acquisition system, we must make gray value of every pixel in allowableerror range in the same intensity under irradiance, which can reflect the actual imageobjectively.Scanner controller, GL847, provides hardware circuitry with calibration, but wemust design steps for gaining correction data according to image acquisition process.After correction, correction data will be preserved. In the later scanning, we can gethigh quality images only send the preserved correction data to the scanner.This paper mainly disscusses the design on reasonable calibration algorithm to getthe best calibration data,and finally verify the calibration datas whether meet therequirements through the image gained by scanner.