Patent ID: 6437825
Filing Date: 2002-08-20
Classification: H04N

Abstract:
An image scanner comprising:a photoelectric conversion element for outputting an image signal in each of a plurality of lines as a unit; A-D converter for converting the output of said photoelectric conversion element into a digital signal; a line memory; means for writing a shading reference signal input beforehand in said line memory at a predetermined bit arrangement; means for dividing the signal read out from said line memory into the shading reference signal and a reference signal for executing image filtering calculation based on the width of the data; means for merging the shading reference signal and the reference signal for executing image filtering calculation into a single unit of data having a width corresponding to a width of data input and output to and from said line memory; means for executing filtering processing by using shading correction processing based on the shading reference signal and by using the reference signal for image filtering calculation on the image signal output from said photoelectric element in each line as a single unit of data; and means for outputting the processed result in each line as a single unit of data.