A solid-state image sensor which includes a pixel section, AD converter, line memory, controller and synthesizer is disclosed. The line memory stores a digital signal output from the AD converter. The controller controls the pixel section and AD converter to subject analog signals of different exposure times to an AD converting process by use of the AD converter and transfer the thus AD-converted signals to the line memory in an accumulation period of charges of one frame. The synthesizer is supplied with digital signals of different exposure times from the line memory, compare a fist signal obtained by adding signals of short and long exposure times with a second signal obtained by amplifying the signal of short exposure time by the ratio of the signal of short exposure time to the signal of long exposure time, select a larger one of the compared signals and output the selected signal.
