Car license plate recognition system realization (1)-the steps of license plate recognition

Realization of Vehicle License Plate Recognition System (1)-General steps of license plate recognition

1. Foreplay

During college, I came into contact with digital image processing by chance. The teacher in charge was very excited at that time, and I slowly fell in love with it. I didn’t know how to achieve my graduation design and chose the realization of the car license plate recognition system at a loss. When I wrote the opening report, I almost couldn’t cry; but recently I found that I like computer vision more and more. Well, I admit that I am poisonous. . . By writing a blog, record the following learning process, I am a rookie at university, there are mistakes or things that need to be improved, please correct me!

Second, the steps of car license plate recognition

Three, method introduction

The following methods are more or less I will use in the process of completing the design, and the following blog will describe them according to my own understanding.

• Image scaling

• Pretreatment

  1. Gaussian smoothing

  2. Median filter

  3. Grayscale

  4. Binarization

• Histogram equalization (may be used)

• Morphological operation

  1. Corrosion operation

  2. Expansion operation

  3. Open operation

  4. Close operation

• Edge detection

  1. Canny edge detection

  2. Sobel operator edge detection

• License plate positioning

• Image correction

  1. Affine transformation

  2. Hough transform to detect straight lines

  3. Perspective transformation

• Remove rivets and license plate frame

  • Jump frequency method

• Character segmentation-vertical projection method to segment characters

• Character recognition-BP neural network

Today’s sharing is here, and I will update it according to my own progress in the future. I hope you will criticize and correct me!