python opencv提取关键帧

import cv2


def main():

    cap = cv2.VideoCapture('H:/开发资料/videowallpaper/video/video4.mp4')

    fps = cap.get(cv2.CAP_PROP_FPS)  # 获取帧速
    print(fps)
    fWidth = cap.get(cv2.CAP_PROP_FRAME_WIDTH)
    print(fWidth)
    fHeight = cap.get(cv2.CAP_PROP_FRAME_HEIGHT)
    print(fHeight)
    fNums = cap.get(cv2.CAP_PROP_FRAME_COUNT)
    success, frame = cap.read()
    i = 0
    while success:
        success, arr = cv2.imencode('.jpg', frame)
        a = arr.tostring()
        fp = open('H:/开发资料/videowallpaper/image/test' + str(i) + '.jpg', 'wb')
        fp.write(a)
        fp.close()
        i = i + 1
        success, frame = cap.read()
    cap.release()
    pass


if __name__ == '__main__':
    main()

不会安装cv 2 到这里来