Automatic extracting method for characters on license plate

An automatic extraction and license plate technology, applied in the field of image processing, can solve problems such as poor adaptability, poor character segmentation and recognition effects, etc., and achieve the effects of strong adaptability, integrity assurance, and small amount of calculation

CN101877050AActive Publication Date: 2010-11-03QINGDAO HISENSE TRANS TECH
0 Cites 38 Cited by

Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
Publication Date
2010-11-03

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention discloses an automatic extracting method for characters on a license plate, which is used for processing a license plate image by a combined global and local binarization method, wherein the global binarization processing is carried out for the license plate image by an Ostu method, the characters and background on the license plate can be accurately separated; and each split single character image is processed by the self-adaptive secondary local binarization method, and the integrity of the character details can be ensured. The method has small operand, high realizability and strong adaptability, can adapt to the license plate images under different environments and illumination conditions, and highlighting the character characteristic can improve the identification accuracy rate of the subsequent characters. The method can be used in an automatic identification system of new vehicle license plates based on digital video / image processing, and for realizing the automatic identification of vehicle license plates in the system.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention belongs to the technical field of image processing, and in particular relates to a method for automatically extracting characters in a vehicle license plate image. Background technique

[0002] With the rapid development of my country's national economy, more and more domestic highways, urban roads, and parking lots are being built, and the requirements for traffic control and safety management are also increasing. Intelligent transportation systems have become an important direction for the development of current traffic management. As a part of the intelligent transportation system, the vehicle license plate recognition system plays a pivotal role. It occupies an irreplaceable important position in the project management of expressways, urban roads and parking lots. Its wide application will definitely help my country's traffic Manage automated processes.

[0003] As a comprehensive real-time computer vision system, the vehicle license ...

Examples

Embodiment 1

[0046] Embodiment one, this embodiment mainly takes the Chinese license plate as an example to elaborate the automatic extraction method of the license plate characters, see figure 1 As shown, it specifically includes the following steps:

[0047] S101. Read the original license plate image.

[0048] The license plate image here can be the license plate image retrieved from the library, or the license plate image actually captured by the road camera from the traffic monitoring system. figure 2 Listed are two license plate images that are captured by a camera and processed for license plate location.

[0049] S102. Perform certain preprocessing on the original license plate image to obtain the background color of the license plate.

[0050] For the judgment of background color, many mature methods have been formed in the current image processing field. In this embodiment, in combination with the inherent characteristics of the license plate background, a method for extracti...