
var popbackground="#f7e6d7" //specify backcolor or background image for pop window
var windowtitle="Image Window"  //pop window title

function detectexist(obj){
  return (typeof obj !="undefined")
}

function popup(imgpath, popwidth, popheight, textdescription){

  function getpos(){
    leftpos=(detectexist(window.screenLeft))? screenLeft+document.body.clientWidth/2-popwidth/2 : detectexist(window.screenX)? screenX+innerWidth/2-popwidth/2 : 0
    toppos=(detectexist(window.screenTop))? screenTop+document.body.clientHeight/2-popheight/2 : detectexist(window.screenY)? screenY+innerHeight/2-popheight/2 : 0
    if (window.opera){
     leftpos-=screenLeft
     toppos-=screenTop
    }
  }

  getpos()

  var winattributes='width='+popwidth+',height='+popheight+',resizable=yes,left='+leftpos+',top='+toppos
  var bodyattribute=(popbackground.indexOf(".")!=-1)? 'background="'+popbackground+'"' : 'bgcolor="'+popbackground+'"'
  bodyattribute += ' onload="reSizeToImage();"'
  if (typeof popwin=="undefined" || popwin.closed)
   popwin=window.open("","",winattributes)
  else{
   //getpos() //uncomment these 2 lines if you wish subsequent popups to be centered too
   //popwin.moveTo(leftpos, toppos)
   popwin.resizeTo(popwidth, popheight+30)
  }
  popwin.document.open()
  popwin.document.write('<html>\n<head>\n');
  popwin.document.write('<script type="text/javascript">\n');
  popwin.document.write('function reSizeToImage(){window.resizeTo(document.images[0].width+50,document.images[0].height+100)\n}\n');
  popwin.document.write('</script>\n<title>'+windowtitle+'</title>\n</head>\n');
  popwin.document.write('<body '+bodyattribute+'>\n<img src="'+imgpath+'" style="margin-bottom: 0.5em"><br>\n <!-- '+textdescription+' --> \n</body>\n</html>\n')
  popwin.document.close()
  popwin.focus()

}

