Detection and Recognition of License Plates Using Color Image Processing

As the number of vehicles is increasing, it is getting difficult to control all the issues related to traffic. So, traffic rules violations related to vehicles are also gradually increasing. Some of the researchers have proposed methods of solving this kind of issues related to vehicles. One of such research area is to identify the vehicles by detecting and recognizing license plates from entire vehicle images. In this paper, different Color image processing techniques were analysed in the context of license plate detection and recognition. In addition, the license plate detection and recognition using various publicly and privately available image datasets, pre-processing techniques, feature extraction techniques, comparison between different color image processing techniques were discussed in detail. It also correlates the parameters and attributes impact in case of different methods applied. Advantages and the limitations of the color image processing were highlighted based on the discussion and analysis. A total of 26 research publications were considered for the time period of 2003–2023. The different types of approaches employed, datasets, metrics, difficulties, and accuracy rates of the license plate detection, tracking, recognition, and localization (LPDTRL) system employing color image processing are also discussed in this work.