In this article, we propose an infrared background clutter suppression technique using a similar method with the haze
removal algorithm based on dark channel prior. The proposed method introduce some modifications to make the original
haze removal algorithm can work in gray-scale infrared image in real-time. In addition, after the background suppression,
we address a efficient algorithm for small target detection, which incorporate Box-Filtering technique into traditional
small infrared target detecting based on LEA. This improved method reduces a large number of redundant calculations in
traditional Local Entropy algorithm by applying the iterative operations instead of using traditional approach. We
provide detailed analysis for time complexity and the results of simulation experiments with real world infrared images
in the final of this work.