Abstract: In order to solve the problem that the situation of single license plate localization algorithm in
complex background is not ideal. A license plate location algorithm based on mathematical morphology
and color characteristics is proposed. Firstly, the new method uses Ostu algorithm to select an optimal
threshold, and according to the threshold carries on binary processing, then by using a new method of
mathematical morphology for image edge detection. Finally combined mathematical morphology with
color characteristic to locate license plate. Experiments show that this new method with higher accuracy
and fewer restrictions on background is superior to traditional or a single method and can be widely used.

Key words: license plate location, Ostu algorithm, image binarization, mathematical morphology;
color characteristics