var SRDelayFactor = 6500;
var SRtImage = "-res/bkg01.jpg";
var SRhtmlID = "bkg";
var SRMaxFileNumber = 10;
var SRTimer = null;
var SRLastFileNumber = 0;

function randombkg()
{

		var SRFilePath = "";
		var SRFileExtension = "";
		var SRRandomNumber = 0;
		var SRMinFileNumber = 1;


		SRFilePath = SRtImage.substring(0,SRtImage.length-6);
		SRFileExtension = SRtImage.substring(SRtImage.length-4,SRtImage.length);
		SRRandomNumber = 0;

		do
		{
		SRRandomNumber = Math.round((Math.random() * (SRMaxFileNumber + 1)) + SRMinFileNumber);
		} while((SRRandomNumber < SRMinFileNumber) || (SRRandomNumber > SRMaxFileNumber))

		if (SRTimer != null) {
		window.clearTimeout(SRTimer);
		SRTimer = null;
  		}
			
		if (SRRandomNumber == SRLastFileNumber)
		{
		SRRandomNumber = SRRandomNumber + SRMinFileNumber;
		}
		
		if (SRRandomNumber > SRMaxFileNumber)
		{
		SRRandomNumber = SRMinFileNumber;
		}

		SRCurrentFileName = SRFilePath + SRRandomNumber + SRFileExtension;

		if (SRRandomNumber < 10)
		{
		SRCurrentFileName = SRFilePath + "0" + SRRandomNumber + SRFileExtension;
		}

		SRLastFileNumber = SRRandomNumber;

		document.getElementById(SRhtmlID).style.background = "url(" + SRCurrentFileName + ")";
		
		SRTimer = window.setTimeout("randombkg()",SRDelayFactor);

}