Sub-pixel edge extraction and recognition method for pantograph pan

The invention discloses a sub-pixel edge extraction and recognition method for a pantograph pan. The method has the following steps: firstly, when a train reaches a fixed position, trigging a photoelectric sensor to enable a fixed camera to work; determining a region of interest of the pan in a pantograph image shot by the camera; and then adding an auxiliary line in the region, accurately positioning image edge points by using a sub-pixel edge extraction algorithm based on a partial area effect, and screening and updating points on a target edge line according to constraint relationships between the internal edge lines of the pan and between the internal edge lines and the external edge lines so as to determine the target edge line. According to the invention, the interference of externaledge lines is eliminated; compared with the prior art, the method is more suitable for more complex edge extraction conditions in actual conditions, increases the inspection constraints of edge points, further improves the e