Tutorial accessing video with Code::Blocks and OpenCV

In this tutorial, we will learn how to access video (ex. web camera) and display it on screen with Code::Blocks and OpenCV for video pre-processing in computer vision project.

Ok, lets jump to tutorial step:

1. We assume that your computer already has Code::Blocks and OpenCV installed. Obviously, both have been integrated well. If not, please see my earlier tutorial associated with them on this blog.
2. Run Code::Blocks and create new C/C++ project.
3. On the main.cpp put this code:

   #include "stdio.h"
   #include "cv.h"
   #include "highgui.h"
   
   int main( int argc, char **argv )
   {
       CvCapture *capture = 0;
       IplImage  *frame = 0;
       int       key = 0;
   
       /* initialize camera */
       capture = cvCaptureFromCAM( 0 );
   
      /* always check */
       if ( !capture ) {
           fprintf( stderr, "Cannot open initialize webcam!\n" );
           return 1;
       }
   
       /* create a window for the video */
       cvNamedWindow( "result", CV_WINDOW_AUTOSIZE );
   
       while(true)
       {
           /* get a frame */
           frame = cvQueryFrame( capture );
   
           /* always check */
           if(!frame ) break;
   
           /* display current frame */
           cvShowImage( "result", frame );
   
           /* exit if user press 'Esc' */
           key = cvWaitKey( 20 );
           if((char)key==27 )
               break;
   
       }
   
       /* free memory */
       cvReleaseCapture( &capture );
       cvDestroyWindow( "result" );
       return 0;
   }
   
   

4. Then build and run project by press “F9”. You can see the result….:D