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Load a camera in OpenCV


#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include<opencv2\opencv.hpp>
#include <opencv2\highgui\highgui.hpp>


int main(int argc, char *argv[])
{
CvCapture *capture = 0;
IplImage *frame = 0;
int key = 0;
/* initialize camera */
capture = cvCaptureFromCAM( 0 );

/* always check */
if ( !capture ) {
printf("Cannot open initialize webcam!\n" );
exit(0);
}

/* create a window for the video */
cvNamedWindow( "result", CV_WINDOW_AUTOSIZE );

while( key != 'q' ) {
/* get a frame */
frame = cvQueryFrame( capture );
/* always check */
if( !frame ) break;
/* display current frame */
cvShowImage( "result", frame );
/* exit if user press 'q' */
key = cvWaitKey( 1 );
}

/* free memory */
cvDestroyWindow( "result" );
cvReleaseCapture( &capture );
return 0;
}

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