A CMOS image sensor with on-chip motion detection and object localization

This paper presents a 64×64 CMOS image sensor with on-chip moving objects detection and localization capability. The sensor is able to operate at triple modes: temporal difference mode, normal full frame intensity mode and region of interest (ROI) intensity mode. Each pixel is equipped with an analog memory (capacitor) and the whole array is hence capable of storing the previous frame. The rows are sequentially selected for readout and frame difference is digitalized into binary events using a global differentiator. An on-chip hardware-implemented clustering-based algorithm processes the events on the fly and localizes moving objects in the scene. The sensor can switch to ROI mode and shoot a zoomed picture of the object. The proposed image sensor has been implemented using UMC 0.18 μm CMOS technology with a die area of 1.5×1.5 mm². The power consumption was measured to only 0.4 mW at 100 FPS.