“…Preprocessing is an indispensable stage, because it can reduce false-alarm rate and increase detection rate through suppressing background clutter and enhancing target signature. So far, a lot of preprocessing algorithms have been brought up, some focus on space domain and some care about frequency domain [1][2][3][4][5], such as two-dimensional least mean square (TDLMS) filter [6], morphological filter [7], high-pass filter [8], median filter [9], nonlinear filter [10,11], local variance weighted information entropy (WIE) filter [12]. It is well known that performance evaluation is an essential part for an effective algorithm, so we focus on evaluating the performance of preprocessing algorithms for IR small target images.…”