## 1 Introduction
It is basically determined that the factors affecting the accuracy of the edge method include edge angle, OSR, binning phase shift (PS), random noise, edge contrast, spatial resolution, etc. The practical research on the MTF measurement algorithm has great application significance. Dr. [PERSON] has made continuous and depth research on the edge method and its practical improvement [2,7,11,14,15,16] and has made some progress in multidirectional MTF measurement, coupling relationship between edge angle, OSR and binning PS, variable OSR model, etc. Moreover, the Infrared and Visible Optical Sensors (IVOS) team from various countries and professional entities has conducted comparative research on MTF measurement and provided open edge reference data sets to construct an exchange platform for effectively improving edge methods [1]. [PERSON] et al. studied the adaptive improved edge method for the MTF measurement of an infrared imaging system [17]. [PERSON] et al. used MTF measured by the edge method as a prior term for remote sensing image restoration [18]. MTF measurement technology using the edge method is also widely used to analyze the spatial resolution characteristics of optical systems in different fields such as medicine, aerospace, and so on [19,20]. However, the edge method is still restricted by the STAS edge requirement, the low robustness, and the non-uniqueness of the measurement results. When RS satellites image natural objects or targets, it is difficult to obtain images containing STAS edges. [PERSON] et al. made use of multi-angle edges to carry out MTF measurement research and pointed out in the prospect that it is necessary to deepen it [21]. The imaging capability of the RS imaging system in the whole field of view is anisotropic, so its MTF(_f_) is also multidirectional. In fact, the STAS condition in ISO 12233 is proposed for measuring MTF in two specific directions, horizontal or vertical. It should be noted that the projection of ROI to the horizontal direction or the direction perpendicular to the edge does not affect the binning process of oversampled ESF construction, nor the MTF result obtained by the Fast Fourier Transform (FFT), but the different projection directions will affect the actual sampling interval, thus affecting the accurate calculation of spatial frequencies (SF), and finally affecting the accurate matching of MTF measured values with SF. There are still some problems to be explored: Does the STAS edge suggested in ISO 12233 refer to a certain angle or a certain angle range? How do the size and location of ROI affect the accuracy of the edge method? Can the influence of low edge contrast and SNR on edge method accuracy be quantified? How to improve the robustness of the edge method and make it suitable for MTF measurement in various imaging fields? To overcome the aforementioned issues, in this paper, the influence of edge angle, OSR, ROI, edge contrast, and random noise on the edge method accuracy is quantitatively analyzed, and a practical multidirectional MTF measurement edge method is proposed based on the above analysis results. The main contribution of this work is summarized below. 1. The main factors that affect the accuracy of the edge method, such as edge angle, OSR, ROI, edge contrast, and random noise, are quantitatively simulated and analyzed so as to provide a universal parameter determination reference for edge method application in RS imaging fields. 2. To further solve the problem of stability, accuracy, and practicability of multidirectional MTF measurement by edge method, according to the quantitative analysis results of influencing factors, an adaptive determination model of optimal OSR and binning PS based on edge angle is proposed. An automatic ROI extraction model of multi-position & multi-size based on edge angle & image size is proposed. By coupling the measurement states of multi-ROI extraction and multi-PS binning, the robustness, accuracy, and practicability of the edge method are comprehensively improved. The rest of the paper is organized as follows.