Original address: https://blog.csdn.net/chenghaibing2008/article/details/52909226
License plate recognition technology is an application of computer video image recognition technology in vehicle license plate recognition, so what is the implementation method of license plate recognition technology?
1. Implementation method of license plate recognition technology
The recognition of vehicle license plate is based on image segmentation and image recognition theory, and the image containing the license plate is analyzed and processed to determine the position of the license plate in the image, and further extract and recognize text characters.
The recognition steps are summarized as: license plate location, license plate extraction, character recognition. The three-step recognition work complements each other, and each has a high efficiency, and the overall recognition rate will increase. The speed of recognition depends on character recognition. The current main application technology of character recognition is the comparison and recognition sample database, that is, all the characters are established as a sample database. After the characters are extracted, the character judgment is realized by comparing the sample database. The intermediate result values such as reliability and inclination; the other is the character recognition technology based on the knowledge of character structure, which more effectively improves the recognition rate and accuracy, and has strong adaptability.
There are two main ways to realize the license plate recognition system: one is the recognition of static images, and the other is real-time recognition of dynamic video streams. The recognition efficiency of static image recognition technology is largely limited by the quality of image capture. It is a single-frame image recognition. At present, the average recognition speed of products in the market is 200 milliseconds; while the recognition technology of dynamic video streams has strong adaptability and recognition speed. Fast, it realizes the recognition of each frame of the video, increases the number of recognition and comparison, and selects the license plate number.
2. Application of license plate recognition technology
License plate recognition is widely used in expressway vehicle management. In electronic toll collection (ETC) system, it is also the main means to identify vehicle identity combined with DSRC technology.
In parking lot management, license plate recognition technology is also the main means of identifying vehicle identity. In the "Technical Requirements for the Collection and Transmission System of Vehicle Image and License Plate Information in Parking Garages (Yards)" constructed by Shenzhen Public Security Bureau, license plate recognition technology has become the main means of vehicle identification.
The license plate recognition technology is combined with the electronic non-stop toll collection system (ETC) to identify the vehicle, and the passing vehicles do not need to stop when passing through the crossing, that is, it can realize the automatic identification of the vehicle identity and automatic toll collection. In the parking lot management, in order to improve the efficiency of vehicle traffic at the entrance and exit, license plate recognition is aimed at vehicles that do not need to charge parking fees (such as monthly trucks and free internal vehicles), and builds unattended fast lanes. Change the management mode of entering and leaving the parking lot.
