求助，c++中opencv读取本地视频出错！

这是代码：

VideoCapture camera;
camera.open("/home/toybrick/workspace/deploy/local_rtsp/tmp/1.mp4");

while (true) {
  Mat img;
  camera >> img;
  if (img.empty()) {
     cerr << "Fail to read image from camera!" << endl;
     break;
  }
}

这是报错信息：
Failed to query video capabilities: Inappropriate ioctl for device
libv4l2: error getting capabilities: Inappropriate ioctl for device
VIDEOIO ERROR: V4L: device /home/toybrick/workspace/deploy/local_rtsp/tmp/1.mp4: Unable to query number of channels
OpenCV(3.4.1) Error: Unspecified error (GStreamer: unable to start pipeline
) in cvCaptureFromCAM_GStreamer, file /builddir/build/BUILD/opencv-3.4.1/modules/videoio/src/cap_gstreamer.cpp, line 890
VIDEOIO(cvCreateCapture_GStreamer (CV_CAP_GSTREAMER_FILE, filename)): raised OpenCV exception:
OpenCV(3.4.1) /builddir/build/BUILD/opencv-3.4.1/modules/videoio/src/cap_gstreamer.cpp:890: error: (-2) GStreamer: unable to start pipeline
in function cvCaptureFromCAM_GStreamer

    sudo dnf install https://download1.rpmfusion.org/ ... usion-free-release-$(rpm -E %fedora).noarch.rpm
    sudo dnf install gstreamer1-libav
请问这两句怎么在板子上安装不起了

我遇到了和你们一样的问题，花了2天时间，解决了，分享一下：
1,安装gstreamer
sudo dnf install https://download1.rpmfusion.org/ ... usion-free-release-$(rpm -E %fedora).noarch.rpm
sudo dnf install gstreamer1-libav
试一下，不行再重装opencv
2，重装opencv，不要用dnf install opencv,源码安装解决一切bug
https://blog.csdn.net/sac761/article/details/103726065