Edge processing method for aerial video image superposition

The invention discloses an edge processing method for aerial video image superposition. The method is implemented on an FPGA and comprises the following steps of converting an RGB color image of a foreground video into a grey-scale image; taking a 3*3 gray value matrix by taking each pixel point in the gray-scale map as a center in sequence, judging whether the nine gray values are equal or not, judging that the pixel point is a non-edge point if the nine gray values are equal, judging that the pixel point is a suspected edge point if the nine gray values are not equal, and marking the suspected edge point in the gray-scale map to form a reference edge map; and taking a 9*9 gray value matrix by taking the suspected edge points as centers in sequence, if any one of 81 gray values is zero, determining that the suspected edge points are true edge points, otherwise, determining that the suspected edge points are false edge points, and removing the false edge points in the reference edge graph to obtain a true edg