关键词: 红外图像, 弱小目标, 方向离散性, 融合, 检测

Abstract: Dim small targets detection in infrared image is one of the key techniques of infrared search and track system.To obtain more perfect detection result，some features of small targets in space and frequency domain are fused to detect those targets.In general，the infrared image can be divided into three categories：background，edges and targets.In space domain，the gray-scale feature is employed.The direction discreteness in frequency domain are extracted as a novel feature of target.Moreover，aiming to improve detection accuracy，it shows how to jointly make decision from gray-scale characteristics and direction discreteness.The targets are separated from background by exploiting the evaluation of Renyi’s information entropy at multi-feature values.A weighted variance growing method is proposed to filter suspicious targets and achieve accurate position by exploiting continuity and consistency of moving target in the image sequences and the variety growth of target.The proposed algorithm is flexible and background-insensitive.A series of evaluations on real battle-plan infrared video also show that the proposed method can effectively detect the small and weak targets.

Key words: infrared image, small and weak targets, direction discreteness, fusion, detection