A license plate comparison method and device
A license plate and comparison technology, applied in the fields of video surveillance, security, and image processing, can solve problems such as image blur, license plate occlusion, and comparison errors, and achieve the effect of improving accuracy.
Active Publication Date: 2020-05-08
BEIJING ICETECH SCI & TECH CO LTD +1
View PDF8 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0003] The current license plate comparison system needs to achieve a high recognition rate under the condition of proper lighting and clear license plate writing. In actual scenarios, license plate character recognition errors are often caused by license plate defacement, blurred imaging, and license plate occlusion. or misalignment
In order to solve the above problems, the method of fuzzy license plate comparison is usually used to solve the problem. However, the comparison accuracy of the existing license plate fuzzy comparison method is low, especially when there are similar license plates, it is easy to cause comparison error results.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
no. 1 example
[0101] Further, the first embodiment of the block entrance license plate gradient map acquisition module 5 includes:
[0102] The optimal perspective transformation parameter acquisition module 51 is used to randomly select 4 matching points as the i-th group of perspective transformation points P i , get the corresponding perspective transformation parameter A i , and then use all matching points to verify the perspective transformation parameters, and count the number SUM that conforms to the perspective transformation parameters i , select SUM i Perspective transformation parameter A with the largest value i as the optimal perspective transformation parameter;
[0103] Entrance license plate perspective transformation diagram acquisition module 52, used to perform perspective transformation processing on the entrance license plate area image according to the optimal perspective transformation parameters, and obtain the perspective transformation diagram of the entrance l...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention provides a license plate comparison method, which includes: using a feature extraction method based on corner point detection to obtain feature points of the entrance license plate area and the exit license plate area respectively; using a feature point matching algorithm to obtain matching points; The position of each character in the license plate area, character blocks for the exit license plate area, calculate the gradient map of the block exit license plate area; obtain the best perspective transformation parameters, obtain the perspective transformation map of the entrance license plate, and obtain the block entrance license plate Perspective transformation map, calculate the gradient map of the perspective transformation map of the entrance license plate of the block; calculate the correlation coefficient between the gradient map of the exit license plate area of each block and the gradient map of the entrance license plate perspective transformation map of the block, and calculate the correlation of all blocks The cumulative value of the coefficient is used as the scoring value of the comparison and output. Compared with the prior art, the present invention can effectively realize the comparison of license plates such as stained, blurred and blocked.
Description
technical field [0001] The invention relates to image processing, video monitoring and security protection, in particular to a license plate comparison method and device. Background technique [0002] With the increasing modernization of cities, the number of motor vehicles continues to increase, and intelligent transportation systems are playing an increasingly important role. License plate comparison technology is an important part of modern intelligent transportation systems and has a wide range of applications. [0003] The current license plate comparison system needs to achieve a high recognition rate under the condition of proper lighting and clear license plate writing. In actual scenarios, license plate character recognition errors are often caused by license plate defacement, blurred imaging, and license plate occlusion. or misalignment issues. In order to solve the above problems, the method of fuzzy license plate comparison is usually used to solve the problem....
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): G06K9/62G06K9/34G06K9/46
CPCG06V30/153G06V10/40G06V10/757G06V20/625
Inventor 班华忠杨振杰尹方始李党
Owner BEIJING ICETECH SCI & TECH CO LTD