Patent ID: 7583295

Claim:
An image signal processing unit, comprising: an image signal receiver that receives an image signal generated by an imaging device that has a plurality of pixels generating pixel signal according to the amount of received light, and whose receiving surface is divided into a plurality of pixel blocks where a plurality of said pixels are arranged; a first addition block that generates high-sensitivity signal by adding up said pixel signals generated by a plurality of said pixels arranged at a predetermined position in said pixel block; a compression block that generates low-sensitivity signal, whose signal level is larger than a first threshold level and that increases in proportion to increasing said high-sensitivity signal, by compressing said high-sensitivity signal for each of said pixel blocks so that said low-sensitivity signal is smaller than a maximum signal level of said pixel signal; and a determination block that determines whether a signal level of said high-sensitivity signal is over said first threshold level; said low-sensitivity signal being output if a signal level of said high-sensitivity signal is over said first threshold level, or said high-sensitivity signal being output if a signal level of said high-sensitivity signal is under said first threshold level.