Imaging system and reproducing system

A replay system for processing a signal compressed after transformation to a signal in a frequency space, comprising:

• decompressing means for decompressing the signal to the signal in the frequency space;
• noise estimating means for estimating the amount of noises of a frequency component except for a zero-order component based on the zero-order component in the signal in the frequency space decompressed by the decompressing means;
• noise reducing means for reducing noises of the frequency component except for the zero-order component based on the amount of noises estimated by the noise estimating means;
• and
• inverting transforming means for transforming the zero-order component and the frequency component except for the zero-order component from which the noises are reduced into a signal in a real space.

An image pickup program executed by a computer, comprising:

• a block extracting step of extracting a block area with a predetermined size from a signal of an image pickup device;
• a transforming step of transforming the signal in the block area extracted by the block extracting step into a signal in a frequency space;
• a noise estimating step of estimating the amount of noises of a frequency component except for a zero-order component based on the zero-order component in the signal in the frequency space transformed by the transforming step;
• a noise reducing step of reducing noises of the frequency component except for the zero-order component based on the amount of noises estimated by the noise estimating step;
• and
• a compressing step of compressing the zero-order component and the frequency component except for the zero-order component from which the noises are reduced.

A replay program comprising:

• a decompressing step of decompressing, into a signal in a frequency space, a signal compressed after the transformation as the signal in the frequency space;
• a noise estimating step of estimating the amount of noises of the frequency component except for the zero-order component based on the zero-order component of the signal in the frequency space decompressed by the decompressing step;
• a noise reducing step of reducing the noises of the frequency component except for the zero-order component based on the amount of noises estimated by the noise estimating step;
• and
• an inverting-transforming step of transforming the zero-order component and the frequency component except for the zero-order component from which the noises are reduced into a signal in a real space.