车牌识别opencv_基于OpenCV 的车牌识别的代码

好的，这里提供一个简单的基于OpenCV的车牌识别的Python代码示例，代码如下：

import cv2
import numpy as np

# 车牌定位
def locate_license_plate(image):
    gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
    blur = cv2.GaussianBlur(gray, (5, 5), 0)
    edges = cv2.Canny(blur, 50, 150)
    contours, _ = cv2.findContours(edges, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
    contours = sorted(contours, key=cv2.contourArea, reverse=True)
    for contour in contours:
        x, y, w, h = cv2.boundingRect(contour)
        ratio = w / h
        if ratio > 2 and ratio < 5:
            plate = image[y:y+h, x:x+w]
            return plate
    return None

# 车牌字符分割
def segment_license_plate(image):
    gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
    _, thresh = cv2.threshold(gray, 0, 255, cv2.THRESH_OTSU)
    contours, _ = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
    contours = sorted(contours, key=cv2.contourArea, reverse=True)
    plates = []
    for contour in contours:
        x, y, w, h = cv2.boundingRect(contour)
        ratio = w / h
        if ratio > 0.2 and ratio < 1.2:
            plate = image[y:y+h, x:x+w]
            plates.append(plate)
    return plates

# 车牌字符识别
def recognize_license_plate(image):
    gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
    # 在这里进行车牌字符识别的算法实现，例如使用SVM或CNN等算法
    # 这里只是一个示例，使用了简单的二值化和轮廓查找
    _, thresh = cv2.threshold(gray, 0, 255, cv2.THRESH_OTSU)
    contours, _ = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
    contours = sorted(contours, key=cv2.contourArea, reverse=True)
    characters = []
    for contour in contours:
        x, y, w, h = cv2.boundingRect(contour)
        ratio = w / h
        if ratio > 0.2 and ratio < 1.2:
            character = gray[y:y+h, x:x+w]
            characters.append(character)
    return characters

# 测试代码
if __name__ == '__main__':
    image = cv2.imread('test.jpg')
    plate = locate_license_plate(image)
    if plate is not None:
        cv2.imshow('license plate', plate)
        characters = segment_license_plate(plate)
        for character in characters:
            cv2.imshow('character', character)
            # 进行车牌字符识别
            recognized_character = recognize_license_plate(character)
            print(recognized_character)
    cv2.waitKey(0)
    cv2.destroyAllWindows()

这个代码示例包括了车牌定位、车牌字符分割和车牌字符识别三个步骤，当然，车牌字符识别部分只是一个简单的示例，需要根据实际情况进行算法实现。