var videopoc = 0;

function showVideoPopup(videoId, width, height)  
    { 
      if (videopoc !== 0)  iwin.close();  
     
      url = "video_popup.php?id=" + videoId; 
      resStr = "resizable=0,scrollbars=0";

                                             // define window oversize
      winPlusWidth = 20;
      winPlusHeight = 90;
                    
      winWidth = width + winPlusWidth;   // calculate window size
      winHeight = height + winPlusHeight;
     
                                             // test if the window is not too large
		heightOK = true;
		
      if (winHeight>screen.availHeight)
        {
         winHeight = screen.availHeight-80;
      	 resStr=",resizable=1,scrollbars=1";
    	 heightOK = false;
      	}
      	
      if (heightOK==false)
        { 
         winWidth = winWidth+22;
      	}	
      								 
      if (winWidth>screen.width)
        { 
          winWidth = screen.width-80;
      	  resStr=",resizable=1,scrollbars=1";
      	}								 

                                                        // calculate centered window position
      winLeft = Math.round((screen.width-winWidth)/2);
      winTop  = Math.round((screen.availHeight-winHeight)/2);

      iwin = window.open(url, "", "left="+winLeft+",top="+winTop+",height="+winHeight+",width="+winWidth+",directories=no,location=no,menubar=no,status=no,toolbar=no,resizable=0,scrollbars=auto");
      
      videopoc++;
      return true;
    }