var ImagesArray = new Array();
var CurrentPosition = 0;
var Opacity = 100;
var StepSize = 5;
var TransitionPause = 20;	//number of milliseconds between each fade step
var TimeToShowImage = 3000;	//how long to show each image

function InitializePhotos()
{
	ImagesArray.push("images/pic_Discovery.gif");
	ImagesArray.push("images/pic_Global.gif");
	ImagesArray.push("images/pic_HGTV.gif");
	ImagesArray.push("images/pic_Wnetwork.gif");

	DownloadImages();
	setTimeout("StartSlideshow()",TimeToShowImage);
}


function DownloadImages()
{
	var PreLoadArray = new Array();

	for(i=0; i < ImagesArray.length; i++)
	{
		PreLoadArray[i] = new Image();
		PreLoadArray[i].src = ImagesArray[i];
	}
}


function StartSlideshow()
{
	FadeOut();
	setTimeout("StartSlideshow()",TimeToShowImage);
}

function FadeOut()
{
	if (Opacity < 0)
		Opacity = 0;

	if (Opacity > 0)
	{
		Opacity -= StepSize;
		SetOpacity("LogoImage", Opacity);
		setTimeout("FadeOut()",TransitionPause);
	}
	else
	{
		if (CurrentPosition == ImagesArray.length-1)
			CurrentPosition = 0;
		else
			CurrentPosition++;

		document.getElementById('LogoImage').src = "";	//incase image takes a sec to download
		document.getElementById('LogoImage').src = ImagesArray[CurrentPosition];
		FadeIn();
	}
}


function FadeIn()
{
	if (Opacity > 100)
		Opacity = 100;

	if (Opacity < 100)
	{
		Opacity += StepSize;
		SetOpacity("LogoImage", Opacity);
		setTimeout("FadeIn()", TransitionPause);
	}
}

function SetOpacity(id, Value)
{
	if (id == "")
		return;

	var object = document.getElementById(id).style;

	object.opacity = (Value / 100);
	object.MozOpacity = (Value / 100);
	object.KhtmlOpacity = (Value / 100);
	object.filter = "alpha(opacity=" + Value + ")";
}