Episode_3_Webcamera_Revolution

Digital optics revolution has reached a point where you can buy cheap digital webcamera ranged from less than 9 euros. In rupiah it should be less than 100.000 Rupiahs. Anyway this webcamera is the most important part in the image processing with opencv which is covered in this blog. Make sure you don't buy a cheap one. Cheap buy is expensive buy. Make sure you buy a fine one, a bit pricey is not a big deal as long as it has good capabilities. In your laptop probably you have also an integrated webcamera. Mostly it sucks. So make sure you have a decent one. I personally am using a cheap webcam from Genius. It was around 100.000 rupiah when I bought it. But it is way much better than my laptop webcam. My webcam is not the best webcam available out there. But it is good enough (for begineer projects especially).

picture 0_my_webcam

Connect your webcam to your computer and make sure everything is properly installed. To use a webcamera in opencv, you need an interface called CvCapture. From the CvCapture interface, you can generate a webcamera image frame with cvQueryFrame.

#include <cv.h>
#include <highgui.h>
 
int main( int argc, char **argv )
{
     CvCapture* capture = cvCaptureFromCAM(0);
     // check if the interface to the webcam is okay.
     if(!capture)
     {
          fprintf(stderr, "Cannot open initialize webcam!\n" );
          return 1;
     }
 
     // create a window for the image from the webcam
     cvNamedWindow("result", CV_WINDOW_AUTOSIZE);
     IplImage* frame; 
     while(cvWaitKey(1) != 'q')
     {
          frame = cvQueryFrame(capture);
          if(frame)
          {
               cvShowImage("result", frame);
          }
          else
          {
               break;
          }
     }
 
     // free memory
     cvDestroyWindow("result");
     cvReleaseCapture(&capture);

     return 0;
}

Then, just show the frame continously in the window. This is the main principle of using your webcamera in opencv. Not such a long tutorial though because ...well... it is very simple. Questions are welcome. Just add it in the post and we will answer it.

picture 1_the_result

p.s : My face is way too handsome :D so I had to make the picture blurry :)