如何基于C++解决RTSP取流报错问题

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
//#pragma comment(lib, "")


using namespace std;
using namespace cv;

void Video_to_Image(Mat& frame);

int main()
{
  //string filename = "Wildlife.wmv";
  string filename = "rtsp://admin:abc.1234@10.12.18.131:554";
  Mat frame;
  VideoCapture cap;
  cap.open(filename);
  if (!cap.isOpened()) {
    cerr <<"ERROR! Unable to open camera\n";
    return -1;
  }

  //--- GRAB AND WRITE LOOP
  cout <<"Start grabbing" <=2)
    {
      cout <<"2s capture" <= 0)
      break;
  }
  cap.release();

  return 0;
}

void Video_to_Image(Mat& frame)
{

  char image_name[PATH_MAX];
  sprintf(image_name, "%s%s", "test_image", ".jpg");
  imwrite(image_name, frame);

}