Automatic recognition algorithm of a car license plate (CLP) is proposed.First the image with a car must be preprocessed.Then based on the steady of the characters on the CLP,a new method to locate CLP in a complex background is presented accurately and rapidly.Finally,the project changing method is used to extract vectors of different dimension for Chinese character, English and Arab alphabet.The recognition result by BP network shows that owing to the high speed and strong recognition ability of BP netw...