Vehicle license plate location based on Harris corner detection

As the characters of license plate have enough corners, a license plate location algorithm of color plate based on Harris corner detection is proposed. The images are first converted from RGB color model to HSI color model and filtered. Detecting corners of saturation component is then carried out according to hue component. Thirdly, the region of license plate is searched by rough and accurate location based on the characteristic of license plate. Finally, the region is binarized and the plate is corrected based on the information of corners. This algorithm can locate license plate correctly in various conditions and the cost of the system is lower than traditional methods.