Question

Im working with openCV, and my output window does not show anything (black screen) when I run the code. I am using my default webcam.

#include "cv.h"
#include "highgui.h"

int main() {
  //simple camera capture program.

  IplImage* newImg;
  CvCapture* capture = cvCaptureFromCAM(0);

  while(1) {
    newImg = cvQueryFrame(capture);
    cvShowImage( "src", newImg );

    if (cvWaitKey(15) == 27) { 
      break;
    }
  }
  return 0;
}

Answer 1

Your code works fine.

The problem is most likely specific to your machine, since OpenCV supports only a few cameras. You might want to use some other library to grab frames from the camera – (V4L, for example?).