Small target detection using the bilateral filter based on target similarity index

This paper presents a new bilateral filter (BF) using the adaptive standard deviation based on the target similarity index (TSI) for small target detection. At first, the threshold value of pixel's TSI in window decides whether any pixel is a potential small target or not. The TSIs of the potential small target pixels are mapped to standard deviations of domain and range filters of the BF by linear mapping and the two standard deviations increase in proportion to the TSI for blurring the small targets. For the more blurred small targets, the filter size according to the TSI is increased. Experimental results demonstrate that the proposed method is more robust and efficient than the conventional methods.