Image Processing and the ARToolkit

Read through this file and notice how it relates to the six steps of the application structure given in the previous post.

/*****************************************************************************/
// modified by Thomas Pintaric, Vienna University of Technology

#ifdef _WIN32
char         *vconf = "flipV,showDlg"; // see video.h for a list of supported parameters
#else
char         *vconf = "";
#endif
/*****************************************************************************/

int   xsize, ysize;
int   thresh = 100;
int   count = 0;

char    *cparam_name = "Data/camera_para.dat";
ARParam  cparam;

char    *patt_name = "Data/patt.hiro";
int      patt_id;
double   patt_width = 80.0;
double   patt_center[2] = {0.0, 0.0};
double   patt_trans[3][4];

static void init(void);
static void cleanup(void);
static void keyEvent( unsigned char key, int x, int y);
static void mainLoop(void);
static void draw( void );

int main(int argc, char **argv)
{
   init();

   arVideoCapStart();
   argMainLoop( NULL, keyEvent, mainLoop );
   return (0);
}

static void keyEvent( unsigned char key, int x, int y)
{
   /* quit if the ESC key is pressed */
   if( key == 0x1b ) {
      printf("*** %f (frame/sec)\n", (double)count/arUtilTimer());
      cleanup();
      exit(0);
   }
}

/* main loop */
static void mainLoop(void)
{
   ARUint8      *dataPtr;
   ARMarkerInfo *marker_info;
   int           marker_num;
   int           j, k;

   /* grab a video frame */
   if( (dataPtr = (ARUint8 *)arVideoGetImage()) == NULL ) {
      arUtilSleep(2);
      return;
   }
   if( count == 0 ) arUtilTimerReset();
   count++;

   argDrawMode2D();
   argDispImage( dataPtr, 0,0 );

   /* detect the markers in the video frame */
   if( arDetectMarker(dataPtr, thresh, &marker_info, &marker_num) < 0)
      cleanup();
      exit(0);
   }

   /* check for object visibility */
   k = -1;
   for( j = 0; j < marker_num; j++) {
      if( patt_id == marker_info[j].id ) {
         if( k == -1 ) k = j;
         else if( marker_info[k].cf < marker_info[j].cf) k = j;
      }
   }

   if( k == -1 ) {
      argSwapBuffers();
      return;
   }

   /* get the transformation between the marker and the real camera */
   arGetTransMat(&marker_info[k], patt_center, patt_width, patt_trans);

   draw();

   argSwapBuffers();
}

/* initialize the video path, read in the marker and camera parameters,
 and setup the graphics window */
static void init( void )
{
   ARParam wparam;

   /* open the video path */
   if( arVideoOpen( vconf ) < 0) exit(0);
   /* find the size of the window */
   if( arVideoInqSize(&xsize, &ysize) < 0) exit(0);
   printf("Image size (x,y) = (%d,%d)\n", xsize, ysize);

   /* read and set the initial camera parameters */
   if( arParamLoad(cparam_name, 1, &wparam)  < 0) {
      printf("Camera parameter load error !!\n");
      exit(0);
   }
   arParamChangeSize( &wparam, xsize, ysize, &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;cparam );
   arInitCparam( &cparam );
   printf("*** Camera Parameter ***\n");
   arParamDisp( &cparam );

   /* read the marker (pattern) file */
   if( (patt_id=arLoadPatt(patt_name)) < 0 ) {
      printf("pattern load error !!\n");
      exit(0);
   }

   /* open the graphics window */
   argInit( &cparam, 1.0, 0, 0, 0, 0 );
}

/* cleanup function called when program exits */
static void cleanup(void)
{
   arVideoCapStop();
   arVideoClose();
   argCleanup();
}

static void draw( void )
{
   double    gl_para[16];
   GLfloat   mat_ambient[]     = {0.0, 0.0, 1.0, 1.0};
   GLfloat   mat_flash[]       = {0.0, 0.0, 1.0, 1.0};
   GLfloat   mat_flash_shiny[] = {50.0};
   GLfloat   light_position[]  = {100.0,-200.0,200.0,0.0};
   GLfloat   ambi[]            = {0.1, 0.1, 0.1, 0.1};
   GLfloat   lightZeroColor[]  = {0.9, 0.9, 0.9, 0.1};

   argDrawMode3D();
   argDraw3dCamera( 0, 0 );
   glClearDepth( 1.0 );
   glClear(GL_DEPTH_BUFFER_BIT);
   glEnable(GL_DEPTH_TEST);
   glDepthFunc(GL_LEQUAL);

   /* load the camera transformation matrix */
   argConvGlpara(patt_trans, gl_para);
   glMatrixMode(GL_MODELVIEW);
   glLoadMatrixd( gl_para );

   glEnable(GL_LIGHTING);
   glEnable(GL_LIGHT0);
   glLightfv(GL_LIGHT0, GL_POSITION, light_position);
   glLightfv(GL_LIGHT0, GL_AMBIENT, ambi);
   glLightfv(GL_LIGHT0, GL_DIFFUSE, lightZeroColor);
   glMaterialfv(GL_FRONT, GL_SPECULAR, mat_flash);
   glMaterialfv(GL_FRONT, GL_SHININESS, mat_flash_shiny);
   glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
   glMatrixMode(GL_MODELVIEW);
   glTranslatef( 0.0, 0.0, 25.0 );
   glutSolidCube(50.0);
   glDisable( GL_LIGHTING );
glDisable( GL_DEPTH_TEST );
}

# posted by Paul Mason @ 11:43 AM