通过对Hu不变矩和仿射不变矩原理的分析，得知不变距特征在图像平移、伸缩、旋转时均保持不变.分析了舰船红外图像的特点，结合Hu不变矩和仿射不变距原理，以大量外场试验数据为基础，对转向的舰船进行了识别研究.从仿真实验得到的大量数据中，发现舰船在转向过程中仍然能很好的识别.

Through analyzing the principles of Hu variant moment and affine variant moment，it has been known that the character of invariant moment would be unchanged when the image is moving，flexing or turning.Combining this principle，and based on a great deal of field experimental data，the characteristics of ship infrared image were analyzed.Then the turning ship has been recognizably studied according to Hu and affine invariant moments.From the quantity of data got in the test，it was found that the turning ship can be recognized finely.