cv::Exception at memory location error occurs - c++

Question

I have a yuv camera.
I convert yuv to bgr (because of opencv use bgr) but I get an exception:
Unhandled exception at 0x76c1a832 in test1.exe: Microsoft C++ exception: cv::Exception at memory location 0x00baee60..
How can I fix it?
#include <opencv/cv.h>
#include <opencv/highgui.h>
#include <opencv2/opencv.hpp>
void main()
{
IplImage* image ;
CvCapture* capture=cvCaptureFromCAM(CV_CAP_ANY);
//cv::Mat input;
cv::Mat output;
cvNamedWindow("webcam",1);
cvGrabFrame( capture );
image = cvRetrieveFrame( capture );
cv::Mat input = cv::cvarrToMat(image);
cv::cvtColor(input,output,CV_YUV2BGR_YUY2);
imshow("webcam", output);
/*
while(1)
{
//get image from Camera
image = cvQueryFrame(capture);
//Iplimage to Mat
cv::Mat input = cv::cvarrToMat(image);
//YUV to RGB, CV_YUV2RGB_NV12 CV_YUV2BGR_NV12 CV_YUV2RGB_YV12 CV_YUV2BGR_YV12 CV_YUV2RGB_IYUV CV_YUV2BGR_IYUV CV_YUV2RGB_UYVY CV_YUV2BGR_UYVY
cv::cvtColor(input,output,CV_YUV2BGR_YUY2);
// Draw image
//cvShowImage("webcam", image);
imshow("webcam", output);
//key = cvWaitKey(30);
if(cvWaitKey(33)>=27)
break;
}
*/
cvReleaseCapture(&capture);
cvDestroyWindow("webcam");
}

Answer 1

The code seems to be correct, but you are not checking whether the image was really retrieved from the capture device. The most likely problem in your code is that you are not retrieving an image and it is an empty Mat you are trying to convert (which is impossible) and this produces the error.
However, if you are already using C++, why don't you use C++ API?