Detecting license plate using texture and color information

Abstract

We consider the problem of detecting car license plate in 2D images. In the first stage of algorithm we enhance the car image at interest regions by estimating image edge density. The enhanced image is then processed using the proposed match filter to extract candidates for car plate. The simplicity of this process makes it suitable for real-time applications. In order to extract car plate among the candidate regions we consider two constraints: geometrical criterion and colour descriptors. The first criterion simply involves geometrical constraints to filter out many of false positives from candidate list. In the second stage of filtering we use colour information on plate to detect license plate among candidate regions. For this purpose we apply multimodal neighbourhood signature algorithm to model license plate. The result of experiments on car images in real complex scene confirms the robustness of the proposed method against severe imaging condition.