WORKSHOP PAPER
Optimal biasing and physical limits of DVS event noise
Abstract
Under dim lighting conditions, the output of Dynamic Vision Sensor (DVS) event cameras is strongly affected by noise. Photon and electron shot-noise cause a high rate of non-informative events that reduce Signal to Noise ratio. DVS noise performance depends not only on the scene illumination, but also on the user-controllable biasing of the camera. This paper explores the physical limits of DVS noise, showing that the DVS photoreceptor is limited to a theoretical minimum of 2x photon shot noise, and discusses how biasing the DVS with high photoreceptor bias and adequate source-follower bias approaches optimal noise performance. Conclusions are supported with pixel-level measurements of a DA VIS346 and analysis of a theoretical pixel model.Keywords
Dynamic Vision Sensor, DVS event noise, noise performance,References
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