【摘要】 针对多重差分航空相机图像检焦精度的问题，提出了一种多重差分空间滤波器参数选取方法。首先，介绍了空间滤波法以及基于空间滤波效应的自动检焦。然后阐述了多重差分滤波检焦法的具体实施过程，并从滤波器输出信号功率谱角度分析了滤波器参数的选取与检焦精度、灵敏度的关系。最后设计动态成像实验，在典型导轨移速53.2 mm/s下采集外景图像，选取不同的滤波器参数分别进行20次像面检测，并将其结果与传统图像检焦算子的检焦效果进行比较。结果表明，本文方法选取的参数使得检焦精度比Brenner算法提高了18%,且检焦系统的最大误差为33.92μm,小于光学系统允许误差(76.8μm),满足实际工作需求。更多还原

【Abstract】 Aiming at the problem of multi-difference aerial camera image detection accuracy, a multi-difference spatial filter parameter selection method is proposed. Firstly, the spatial filtering method and the automatic focusing based on the spatial filtering effect are introduced. Secondly, the implementation process of multi-difference filter focusing method is introduced, and the relationship between the selection of filter parameters and the focusing accuracy as well as the sensitivity is analyzed from the view of the power spectrum of filter output signal. Finally, the dynamic imaging experiment is designed, and the location images are collected under the typical guide speed of 53.2mm/s. Different filter parameters are selected to detect the image plane for 20 times, and the focusing effect is compared with that of the traditional image-focusing operator. The results show that the parameters selected by the multi-difference filtering method in this paper improve the focusing accuracy by 18% compared with the Brenner algorithm. And the maximum error of the focusing system is 33.92 μm, less than the allowable error of the optical system(76.8 μm), which meets the practical requirements.更多还原