Raindrops size from video and image processing

This paper describes a videosonde designed for providing shape and size of raindrops. It makes use of a single CCD camera and image processing to detect raindrops, to segment and measure shape and size of each detected particle. Depth is obtained by one fixed camera with 2 lights, which is a key feature of the video sonde. Raindrops are detected by their 2 shadows. As no model are accurate to represent raindrops, image processing uses a-contrario method for detection, and constraint filtering for matching. Results are evaluated on glass ball and real rain simulator.