Shenzhen Rakinda Technologies Co., Ltd.

License plate number recognition, also known as vehicle license plate recognition, vehicle license plate recognition, etc., it is the application of computer video image recognition technology to vehicle license plate recognition to extract and identify the license plate number in the image information.
The principle of license plate number recognition is roughly divided into four main modules of image acquisition, license plate positioning, character segmentation and character recognition, and then the software programming is used to realize each part and finally determine the license plate and output the license plate number and other related information.

All environmental cameras are installed at a location where the vehicle is 4-6 m away from the camera and the license plate width size is 120-160. Since the relative rotation angles of license plate and body are different, it will have an impact on the captured image and cause image distortion. To solve this problem, we designed an automatic correction system to eliminate this phenomenon. The license plate on the camera appears parallel.

1. The standard lane without bending angle, the determination range of license plate recognition area is 4-5 m interval section.
2. The bend angle is too big need to make angle judgment, the license plate parallelism judgment, the license plate recognition best distance 4-5 m after the license plate turns right.
3. The parallel angle is not more than 15°, and the slant angle is not more than 45°.
4. The individual width of the road surface is not more than 4.5 m.
5. The site environment pays attention to the rainwater well cover and the setting of the protection bar.
6. License plate recognition direction and location should try to avoid similar items.
Non-standard environment in the license plate recognition of the installation location judgment for.
1, to the left turn lane camera installed in the right side of the direction of travel.
2. To the right turn lane camera installed in the left side of the direction of travel.
3. To the left or right turn direction of travel lane need to set up the camera in the left or right respectively.
4. The camera needs to be set at the outer bend to ensure the parallelism of the license plate.
A standard license plate recognition system includes server, management computer, entrance/exit recognition camera, display all-in-one machine, entrance/exit gate, software dongle and so on. Among them, the computer vision system is the core part. This paper introduces an image processing technology based on DSP chip TMS320DM642, which uses digital image processing algorithm for image enhancement and edge detection. This utility model can realize image comparison, automatic toll collection and automatic access of fixed vehicles.