A bump-circuit-based motion detector using projected-activity histograms

An analog VLSI for real-time motion analysis has been developed using CMOS bump circuits for pixel-level activity detection and projected activity histograms for motion detection. The pixel-level time derivative operation is carried out on a video sequence of images by the bump circuit built in each pixel to generate so-called activity maps. The data in the activity map are then projected onto x- and y-axes, and motion analysis is conducted using the activity histograms produced by projection. Therefore, the core circuitries for motion analysis are laid out at the periphery of the image sensor array. The proposed hardware algorithm has been verified by computer simulation. A proof-of-concept chip was fabricated in a 0.35-μm CMOS double-poly triple-metal technology and the measurement results from the test chip are presented to demonstrate the operation.