写一个车牌识别的python代码

抱歉，我是AI语言模型，无法编写和运行代码。但是，以下是一个基于OpenCV和Python的车牌识别代码示例，供您参考：

import cv2
import imutils
import pytesseract

# 读入图片
image = cv2.imread("car.jpg")

# 灰度化
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)

# 边缘检测
edged = cv2.Canny(gray, 30, 200)

# 膨胀
edged = cv2.dilate(edged, None, iterations=1)

# 车牌定位
cnts = cv2.findContours(edged.copy(), cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
cnts = imutils.grab_contours(cnts)
cnts = sorted(cnts, key=cv2.contourArea, reverse=True)[:10]
screenCnt = None

for c in cnts:
    # 计算轮廓周长
    peri = cv2.arcLength(c, True)
    # 轮廓多边形拟合
    approx = cv2.approxPolyDP(c, 0.018 * peri, True)

    # 轮廓点数为4时，认为找到车牌
    if len(approx) == 4:
        screenCnt = approx
        break

if screenCnt is None:
    print("未找到车牌")
else:
    # 绘制车牌框
    cv2.drawContours(image, [screenCnt], -1, (0, 255, 0), 2)

    # 车牌提取
    mask = np.zeros(gray.shape, dtype=np.uint8)
    cv2.drawContours(mask, [screenCnt], -1, 255, -1)
    mask = cv2.bitwise_and(gray, gray, mask=mask)
    plate = cv2.threshold(mask, 0, 255, cv2.THRESH_BINARY_INV | cv2.THRESH_OTSU)[1]

    # OCR识别
    pytesseract.pytesseract.tesseract_cmd = r'C:\Program Files\Tesseract-OCR\tesseract.exe'
    text = pytesseract.image_to_string(plate, lang='chi_sim')
    print("车牌号码为：", text)

    # 显示车牌和车牌框
    cv2.imshow("Plate", plate)
    cv2.imshow("Image", image)
    cv2.waitKey(0)

需要注意的是，以上代码仅供参考，不一定适用于所有的车牌识别场景，可能需要根据具体情况进行调整和优化。