Retrieving Gray-Level Information from a Binary Sensor and its Application to Gesture Detection

We report on the use of a CMOS Contrast-based Binary Vision Sensor (CBVS), with embedded contrast extraction, for gesture detection applications.
The first advantage of using this sensor over commercial imagers is a dynamic range of 120dB, made possible by a pixel design that effectively performs auto-exposure control. Another benefit is that, by only delivering the pixels detecting a contrast, the sensor requires a very limited bandwidth.

We leverage the sensor's fast 150us readout speed, to perform multiple reads during a single exposure; this allows us to estimate gray-level information from the otherwise binary pixels.
As a use case for this novel readout strategy, we selected in-car gesture detection, for which we carried out preliminary tests showing encouraging results.