Input from Camera
To input a live stream from a camera we have to call cvCreateCameraCapture(). The argument which is passed in this function is a camera ID number as its argument.
Of course, this is important only when multiple cameras are available. The default value is –1, which means “just pick one”; naturally, this works quite well when there is only one camera to pick.
The cvCreateCameraCapture() function returns the same CvCapture* pointer, which we can hereaft er use exactly as we did with the frames grabbed from a video stream.
Example
#include "cv.h"
#include "highgui.h"
int main(int argc, char** argv)
{
cvNamedWindow("cameraDisplay", CV_WINDOW_AUTOSIZE);
CvCapture * capture;
capture = cvCreateCameraCapture(0);
IplImage* frame;
while (1)
{
frame = cvQueryFrame(capture);
if (!frame)
break;
cvShowImage("cameraDisplay", frame);
char c = cvWaitKey(10);
if (c == 27)
break;
}
cvReleaseCapture(&capture);
cvDestroyWindow("cameraDisplay");
}
