Patent ID: 8553111

Claim:
A noise reduction system for performing noise reduction processing for an image signal taken in from an image pickup system, comprising: a local area extracting unit which sequentially extracts, from the image signal, a local area including a target pixel for which the noise reduction processing is performed; a first noise reducing unit which reduces random noise for the local area; a second noise reducing unit which reduces impulsive noise for the local area and includes an index coefficient calculating unit which is configured to calculate an index coefficient indicating a degree of impulsiveness concerning at least one pixel of the local area; and a combining unit which combines an image signal obtained by the first noise reducing unit and an image signal obtained by the second noise reducing unit., wherein the combining unit has a selecting unit which is configured to select the image signal obtained by the second noise reducing unit from the image signal obtained by the first noise reducing unit and the image signal obtained by the second noise reducing unit if the index coefficient is not less than a predetermined threshold value.