Character region extraction of wheel water meter based on object detection

Abstract

Currently, research on automatic meter reading mainly focuses on meter reading recognition, while neglecting the fundamental role of counter detection in the entire automatic meter reading system. In fact, only by accurately locating the counter area can the influence of dial factors be completely eliminated, thus ensuring the accuracy and reliability of subsequent water meter reading recognition. In view of this phenomenon, the focus of this study is on the counter detection stage. Firstly, a target detection-based image skew correction method is proposed to solve the problem of image skew caused by shooting angle and other reasons. This method ensures the accuracy of subsequent counter area positioning and the neatness of cutting effect. Secondly, a semi-supervised target detection training method is proposed to solve the problem of time and manpower costs required in large-scale data situations. In addition, we have made publicly available a dataset containing 1070 water meter images for non-commercial purposes, which can be obtained from the Github¹. Finally, we evaluated our model on three completely different datasets and compared it with the best positioning results of other models. The experimental results show that compared with other models, the proposed model in this paper has improved the positioning accuracy by 5.82%, 5.96%, and 9.20% on three datasets respectively. Furthermore, in the final visualization comparison, the model accurately identifies the counter region even when faced with complex real-world environments.