Design and recognition of a circular coded marking point

In this paper, an innovative ring-coded marker point design and its recognition method are proposed to effectively solve the difficulties in localization and detection due to wear and tear or occlusion in complex environments. By adding solid circles as starting characters above and below the marker points, the localization accuracy and recognition stability are significantly improved. Experiments prove that the recognition accuracy of the method is 98.9% even when the occlusion rate is not more than 50%, which meets the requirements of high-precision measurement. The method achieves effective image processing through global binarization and adaptive determination of threshold by Otsu algorithm, and accurately locates the coded marker points through boundary extraction, parameter fitting and other techniques. In addition, this paper discusses the application of coded marker points in photogrammetry, emphasizing the important role of coded marker points in fast and accurate measurement of 3D close-up photography as well as the conversion of images from 2D to 3D. This research not only improves the accuracy and automation of visual measurement techniques, but also provides a new solution for precise positioning and accurate identification in complex environments, which has a wide range of application prospects.