Patent ID: 8422819

Claim:
An image processing apparatus comprising: a noise removal circuit which removes noise from a pixel signal read out from an image sensor on which pixels are arranged in matrix when a level of the pixel signal readout falls outside a range defined by a first threshold level and a second threshold level with respect to a signal on an identical row; a cyclic calculation circuit which makes a cyclic calculation between signals on the same column with respect to the pixel signal readout in which the noise is removed by said noise removal circuit; and a column offset detection circuit which detects a column offset component for each column based on a calculation result of said cyclic calculation circuit, wherein when a difference between a previously calculated cyclic calculation value and a current pixel signal value falls outside a range defined by a third threshold level and a fourth threshold level upon making the cyclic calculation by said cyclic calculation circuit, said column offset detection circuit detects the column offset component using a previously calculated cyclic calculation result without making the cyclic calculation using the current pixel signal value.