利用python-opencv识别红绿灯

import cv2
import numpy as np

cap = cv2.VideoCapture("红绿灯.mp4")  # 导入视频
while True:
    ret, frame = cap.read()
    if ret == False:
        break
    frame = cv2.resize(frame, (1620, 900))  # 修改视频尺寸
    img = frame[100:500, 300:800]
    hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)  # 转换hsv颜色空间
    # 红灯
    lower_hsv_red = np.array([157, 177, 122])  #
    upper_hsv_red = np.array([179, 255, 255])
    mask_red = cv2.inRange(hsv, lowerb=lower_hsv_red, upperb=upper_hsv_red)

    red_blur = cv2.medianBlur(mask_red, 7)
    # 绿灯
    lower_hsv_green = np.array([49, 79, 137])
    upper_hsv_green = np.array([90, 255, 255])
    mask_green = cv2.inRange(hsv, lowerb=lower_hsv_green, upperb=upper_hsv_green)
    green_blur = cv2.medianBlur(mask_green, 7)
    red_color = np.max(red_blur)
    green_color = np.max(green_blur)
    if red_color == 255:
        print('红')
        cv2.rectangle(frame, (660, 420), (400, 300), (0, 0, 255), 2)  # 按坐标画出矩形框
        cv2.putText(frame, "red", (500, 280), cv2.FONT_HERSHEY_COMPLEX, 1, (0, 0, 255), 2)  # 显示文本信息
    elif green_color == 255:
        print('绿')
        cv2.rectangle(frame, (660, 420), (400, 300), (0, 255, 0), 2)
        cv2.putText(frame, "green", (500, 280), cv2.FONT_HERSHEY_COMPLEX, 1, (0, 255, 0), 2)
    cv2.imshow('frame', frame)
    red_blur = cv2.resize(red_blur, (200, 150))
    green_blur = cv2.resize(green_blur, (200, 150))
    cv2.imshow('red', red_blur)
    cv2.imshow('green', green_blur)
    c = cv2.waitKey(1)
    if c == 1:
        break

结果如下图所示