An Event Based Dynamic Vision System

Event Based Dynamic Vision System

Conventional vision sensors see the world as a series of frames. Successive frames contain enormous amounts of redundant information, wasting memory access, RAM, disk space, energy, computational power and time. In addition, each frame imposes the same exposure time on every pixel, making it difficult to deal with scenes containing very dark and very bright regions.

The Dynamic Vision Sensor (DVS, http://siliconretina.ini.uzh.ch) solves these problems by using patented technology that works like your own retina. Instead of wastefully sending entire images at fixed frame rates, only the local pixel-level changes caused by movement in a scene are transmitted – at the time they occur. The result is a stream of events at microsecond time resolution, equivalent to or better than conventional high-speed vision sensors running at thousands of frames per second. Power, data storage and computational requirements are also drastically reduced, and sensor dynamic range is increased by orders of magnitude due to the local processing.

We have developed a small embedded system consisting of an ARM7 microcontroller with a DVS sensor, that outperforms conventional vision sensors with PCs in many tasks requiring computer vision. Examples of these are computation of optic flow or high-speed tracking of simple objects in cluttered backgrounds. Example projects include the "Pencil Balancer" and the soon to be started "Swarm of Autonomous Indoor Quadrocopters".


Contact

Jörg Conradt