Assertion failed (size.width>0 && size.height>0) Qt with OpenCV

Question

I have a problem to display an image on Qt Creator with OpenCV library.

I have a program that displays an image when a button is pressed. When I run it, it gives me

OpenCV Error: Assertion failed (size.width>0 && size.height>0) in cv::imshow, file C:\\builds\\2_4_PackSlave-win64-vc12-shared\\opencv\\modules\\highgui\\src\\window.cpp, line 261 The program has unexpectedly finished.

using namespace cv;

void MainWindow::on_start_clicked()
{

    Mat src = imread("C:/Users/Amr/Documents/untitled7/layout.jpeg",CV_WINDOW_AUTOSIZE);
    namedWindow("src",CV_WINDOW_AUTOSIZE);
    imshow("src",src);
    waitKey(0);
    destroyWindow("src");
}

but when i try this program it works very good

using namespace cv;

void MainWindow::on_start_clicked()
{

     Mat src (500,500,CV_8UC3,Scalar(255,0,0));
    namedWindow("src",CV_WINDOW_AUTOSIZE);
    imshow("src",src);
    waitKey(0);
    destroyWindow("src");
}

I feel that the problem is in the directory but I don't know what it is. I have tried to change / to \\ or // but still getting this error.

Answer 1

Assuming that the path is correct, using CV_WINDOW_AUTOSIZE doesn't make sense. Use IMREAD_XXX :

Mat src = imread("C:/Users/Amr/Documents/untitled7/layout.jpeg", IMREAD_COLOR);

However, double check the path, and remember that "image.jpeg" is different from "image.jpg". And... are you sure "untitled7" is correct?