Python OpenCV读取并显示USB UVC摄像头

1. 安装Python， 略。

2. 安装 OpenCV:        

pip install opencv-python

3. 预览摄像头画面脚本：

import cv2

cap = cv2.VideoCapture(0, cv2.CAP_DSHOW)

if not (cap.isOpened()):
    print("Could not open video device")

cap.set(cv2.CAP_PROP_FRAME_WIDTH, 640)
cap.set(cv2.CAP_PROP_FRAME_HEIGHT,480)
cap.set(cv2.CAP_PROP_FOURCC, cv2.VideoWriter.fourcc('Y', 'U', 'Y', 'V'))

while(True):    
    # Capture frame-by-frame    
    ret, frame = cap.read()    
    
    cv2.imshow('frame', frame)
    
    #Waits for a user input to quit the application    
    if cv2.waitKey(1) & 0xFF == ord('q'):    
        break
    
cap.release()
cv2.destroyAllWindows()