为有效地识别红外图像中的弱小目标，在分析传统识别方法的基础上，提出了一种利用十字窗口识别红外弱小目标的新方法.该方法在待识别点上、下、左、右四个方向以目标大小选取四个参考点构造十字形识别窗口，根据待识别点与参考点之间的灰度梯度识别该像素点是否为目标像素.该方法无需预测背景，可以在低信噪比、强度变化剧烈的图像中获得较高的识别率与较低的虚警率.实验结果表明了该算法的有效性.

To detect dim and small target in infrared image, a novel method based on cross window was presented through analyzing traditional methods. The method constructed cross detection window with up, down, left and right reference points around candidate detected point according to the size of target. Based on the grads gradient between candidate detected point and reference points, the points belong to target can be identified. The method does not need background prediction, and achieves higher detection probability and lower false alarm probability in infrared image with low signal noise ratio and strong background. Experimental results show the validity of the method.