var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";

function decode64(input){

	var output = "";
	var chr1, chr2, chr3;
	var enc1, enc2, enc3, enc4;
	var i = 0;
	// remove all characters that are not A-Z, a-z, 0-9, +, /, or =
	input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
	do {
		enc1 = keyStr.indexOf(input.charAt(i++));
		enc2 = keyStr.indexOf(input.charAt(i++));
		enc3 = keyStr.indexOf(input.charAt(i++));
		enc4 = keyStr.indexOf(input.charAt(i++));

		chr1 = (enc1 << 2) | (enc2 >> 4);
		chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
		chr3 = ((enc3 & 3) << 6) | enc4;

		output = output + String.fromCharCode(chr1);

		if (enc3 != 64) {
			output = output + String.fromCharCode(chr2);
		}
		if (enc4 != 64) {
			output = output + String.fromCharCode(chr3);
		}
	} while (i < input.length);
   return output;

}

function popup(){
	var arg = popup.arguments, win, thisWidth, thisHeight;
	thisWidth = ( arg[1] ) ? arg[1] : 450 ;
	thisHeight = ( arg[2] ) ? arg[2] : 550 ;
	win = window.open(arg[0],'','scrollbars=yes,toolbar=no,location=no,status=no,resizable=yes,'+set_screen_position(thisWidth,thisHeight));
	win.focus();
}

function set_screen_position(){
	var arg = set_screen_position.arguments, widthW = screen.width, heightW = screen.height, left, top;
	top = Math.round((heightW-arg[1])/2); left = Math.round((widthW-arg[0])/2);
	return 'width='+arg[0]+',height='+arg[1]+',top='+top+',left='+left;
}