OpenCV 设置读取视频编码的问题

money9sun

   小弟的代码：

#-*- coding: utf-8 -*-
import face_recognition
import dlib
import cv2
import time
from exceptions import Exception

# 调用openCV 库，获取摄像头影像
stream = cv2.VideoCapture(0)
#stream.set(6,cv2.VideoWriter_fourcc(*'MJPG'))
stream.set(6,cv2.VideoWriter_fourcc('M','J','P','G'))
stream.set(3,640)
stream.set(4,480)
stream.set(5,30)


  运行起来出这个错误：
(process:1301): GStreamer-CRITICAL **: gst_element_get_state: assertion 'GST_IS_ELEMENT (element)' failed
VIDEOIO ERROR: V4L: Property <unknown property string>(6) not supported by device
VIDEOIO ERROR: V4L2: Unable to get property <unknown property string>(6) - Invalid argument


我已经把opencv重新编译 带了V4L=ON 这个参数，请问这个问题怎么解决呢