How can I resolve showing empty image in opencv? - c++

Question

I use opencv2.4.9 whith visual studio 2010
when I have to show an image program display the empty window and not show image
and its my code:
#include<opencv2\highgui\highgui.hpp>
#include<opencv2\core\core.hpp>
#include<opencv\cv.h>
int main(int argc,char**argv[]) {
IplImage* img1=cvLoadImage("C:\opencv\sources\samples\cpp\board.jpg");
cvNamedWindow("img1",CV_WINDOW_AUTOSIZE);
cvShowImage("img1",img1);
cvWaitKey(0);
cvReleaseImage(&img1);
}

Answer 1

The problem is in the way you wrote the path of the image. you should not use the escape character alone. You can solve it by one of these:
IplImage* img1=cvLoadImage("C:\\opencv\\sources\\samples\\cpp\\board.jpg");
Or:
IplImage* img1=cvLoadImage("C:/opencv/sources/samples/cpp/board.jpg");
Or:
IplImage* img1=cvLoadImage(R"(C:\opencv\sources\samples\cpp\board.jpg)");
BTW, you are using C interface which is really too out of data. If you do not have a REAL reason to use it, please do not. The equivalent code that use C++ is:
int main(int argc,char**argv[]) {
cv::Mat img1=cv::imread("C:\\opencv\\sources\\samples\\cpp\\board.jpg");
cv::namedWindow("img1",CV_WINDOW_AUTOSIZE);
cv::imshow("img1",img1);
cv::waitKey(0);
//No need to release manually
}

Answer 2

if you use Mat then you can use:
if (frame1.empty())
{
std::cout << "no image";
break;
}
then if the image not empty you should use more delay to display the images.
for example you can use:
waitKey(100);