尝试使用opencv，python访问网络摄像头（视频0），我收到以下错误：
cap = cv2.VideoCapture(0)
pos_frame = cap.get(cv2.CAP_PROP_POS_FRAMES)
I0626 11:31:59.156796 18887 net.cpp:744] Ignoring source layer silence_rpn_bbox_pred
VIDEOIO ERROR: V4L2: getting property #1 is not supported
VIDEOIO ERROR: V4L2: getting property #1 is not supported -1.0 frames
VIDEOIO ERROR: V4L2: getting property #1 is not supported
VIDEOIO ERROR: V4L2: getting property #7 is not supported
任何线索都将受到赞赏