Abstract:

In the catenary power-off maintenance operation, the position of the hanging ground wire is determined by the pillar number on the work ticket. Therefore, the research on the identification of the pillar number plate of the catenary is of great significance for the automatic monitoring of the hanging ground wire. Therefore, a pillar number recognition method based on contrast limited adaptive histogram equalization (CLAHE) is proposed. The contrast constrained adaptive histogram equalization and median filter are used to preprocess the image, the minimum region method and morphological transformation are used to extract the number plate region, and then the connected domain and template matching are used to identify the pillar number characters on the number plate. In the recognition process, the distribution law of pillar numbers is considered to verify the recognition results of pillar numbers. Experiments are carried out on the recognition software platform jointly developed by Halcon and C#, and the mean square deviation and peak signal-to-noise ratio of CLAHE and histogram equalization are compared. The results show that this method greatly improves the accuracy of pillar number recognition.

Key words: Hanging ground wire, identification of catenary pillar number plate, contrast limited adaptive histogram equalization, morphological transformation, connected domain method