Patent ID: 7453490

Claim:
A method of compensating for non-uniformity in an image signal, the method comprising: performing a characterization operation on an endoscopic optical image portion of an input image signal from an image sensor that comprises a pixel array of imaging elements, the endoscopic optical image portion of the image signal originating from an endoscopic optical image that is incident on at least a portion of the optical image sensor, which portion is subject to non-uniform illumination and non-uniform optical characteristics, the portion of the input signal originated by the endoscopic optical image requiring compensation to render it suitable for output as a video signal; establishing, based at least in part on the characterization operation, one or more correction factors to compensate for the non-uniform illumination and non-uniform optical characteristics in the endoscopic optical image portion of the input image signal from the sensor; acquiring selected endoscopic image data from the endoscopic optical image portion of the input image signal; and applying, using at least one of the established correction factors, a compensation operation on the endoscopic optical image portion of the input image signal to address the non-uniform illumination and non-uniform optical characteristics in the signal before conversion to an output video signal; wherein the compensation operation is determined and provided using pixel-by-pixel correction factors to correct non-uniformities arising at individual pixel locations.