Research on Monocular Vision Positioning Technology Used in Water Meter Verification

This paper mainly studies the method of water meter plum pin precise positioning, and proposes a positioning method of water meter plum blossom needle with high positioning accuracy, anti-jamming performance and versatility. The method firstly uses the three-frame difference method to obtain the contour area of the plum blossom needle dynamically, secondly the convex hull algorithm to extract the boundary information of the plum blossom needle, and then uses the minimum encircling circle algorithm to create the circumscribed circle of the plum blossom needle. By traversing the distance between each vertex and the circumcircle pixel, we find the exact coordinate position and achieve the precise positioning of the plum blossom needle. The test results show that the precision of the water meter can reach 97.46%-99.133% by accurately positioning the plum blossom needle. On the one hand we can accurately locate the plum blossom needle with the bubble inside the dial, on the other hand, this method covers the shortage of the traditional photoelectric pulse verification method which can only detect the water meter of the plum blossom needle at the same position.