A 26.5 nJ/px 2.64 Mpx/s CMOS vision sensor for Gaussian pyramid extraction

This paper introduces a CMOS vision sensor to extract the Gaussian pyramid with an energy cost of 26.5 nJ/px at 2.64 Mpx/s, thus outperforming conventional solutions employing an imager and a separate digital processor. The chip, manufactured in a 0.18 μm CMOS technology, consists of an arrangement of 88 × 60 processing elements (PEs) which captures images of 176 × 120 resolution and performs concurrent parallel processing right at pixel level. The Gaussian pyramid is generated by using a switched-capacitor network. Every PE includes four photodiodes, four MiM capacitors, one 8-bit single-slope ADC and one CDS circuit, occupying 44 × 44 μm². Suitability of the chip is assessed by using metrics pertaining to visual tracking.