var resizeDelay = 10;
var resizeIncrement = 25;
var imgCache = new Object();

function getCacheTag (imgElement) {
return imgElement.src + "~" + imgElement.offsetLeft + "~" + imgElement.offsetTop;
}

function cachedImg (imgElement, increment) {
this.img = imgElement;
this.cacheTag = getCacheTag(imgElement);
this.originalSrc = imgElement.src;

var h = imgElement.height;
var w = imgElement.width;
this.originalHeight = h;
this.originalWidth = w;

increment = (!increment) ? resizeIncrement : increment;
this.heightIncrement = Math.ceil(Math.min(1, (h / w)) * increment);
this.widthIncrement = Math.ceil(Math.min(1, (w / h)) * increment);
}

function resizeImg (imgElement, percentChange, newImageURL) {
var pct = (percentChange) ? percentChange / 100 : 1;
var cacheTag = imgElement.getAttribute("cacheTag");
if (!cacheTag) {
cacheTag = getCacheTag(imgElement);
imgElement.setAttribute("cacheTag", cacheTag);
}

var cacheVal = imgCache[cacheTag];
if (!cacheVal) {
imgCache[cacheTag] = new Array(new cachedImg(imgElement), pct);
} else {
cacheVal[1] = pct;
}

if (newImageURL)
imgElement.src = newImageURL;

resizeImgLoop(cacheTag);
return true;
}


function resizeImgLoop (cacheTag) {
var cacheVal = imgCache[cacheTag];
if (!cacheVal)
return false;

var cachedImageObj = cacheVal[0];
var imgElement = cachedImageObj.img;
var pct = cacheVal[1];
var plusMinus = (pct > 1) ? 1 : -1;
var hinc = plusMinus * cachedImageObj.heightIncrement;
var vinc = plusMinus * cachedImageObj.widthIncrement;
var startHeight = cachedImageObj.originalHeight;
var startWidth = cachedImageObj.originalWidth;

var currentHeight = imgElement.height;
var currentWidth = imgElement.width;
var endHeight = Math.round(startHeight * pct);
var endWidth = Math.round(startWidth * pct);

if ( (currentHeight == endHeight) || (currentWidth == endWidth) )
return true;

var newHeight = currentHeight + hinc;
var newWidth = currentWidth + vinc;
if (pct > 1) {
if ((newHeight >= endHeight) || (newWidth >= endWidth)) {
newHeight = endHeight;
newWidth = endWidth;
}
} else {
if ((newHeight <= endHeight) || (newWidth <= endWidth)) {
newHeight = endHeight;
newWidth = endWidth;
}
}

imgElement.height = newHeight;
imgElement.width = newWidth;

if ((newHeight == cachedImageObj.originalHeight) || (newWidth == cachedImageObj.originalwidth)) {
imgElement.src = cachedImageObj.originalSrc;
}

setTimeout("resizeImgLoop('" + cacheTag + "')", resizeDelay);
}