Image pickup system for reducing noise attributable to an image pickup device

A method for reducing noise in an image produced by an image pickup system having an image pickup device configured to convert an optical image into a signal, comprising the steps of:

• a) extracting a block area of a predetermined size from the signal provided by the image pickup device;
• b) transforming the signal in the block area extracted in step (a) into a signal in a frequency space;
• c) obtaining a temperature of the image pickup device;
• d) obtaining a gain of the signal:
• e) estimating an amount of noise in a frequency component except for a zero-order component based on a combination of the zero-order component in the signal in the frequency space transformed at step (b), and the temperature and signal gain respectively obtained at steps (c) and (d);
• f) reducing noise in the frequency component except for the zero-order component based on the amount of noise estimated at step (e);
• and
• g) compressing the zero-order component and the frequency component except for the zero-order component from which the noise is reduced, to thereby obtain a high quality image.