Snowfall Noise Elimination Using a Time Median Filter

Abstract

In the surveillance of moving objects with TV cameras, snowfall prevents the clear surveillance. Therefore it would be desirable that snowflakes are eliminated from the surveillance images. In this paper, we tried to eliminate snowflakes by using time filtering. First we described time filter, then we estimated the performance of the filter theoretically by using a stochastic model that utilizes the size and velocity of a snowflake. Moreover, we considered the effect of the filter to the moving objects such as walking persons or running cars. Finally we applied the filter to the real images and obtained good results.