var util = {
	setEvent: function(obj,eventType,func){
		if(this.isIE) {
			obj.setAttribute(eventType,new Function(func));
		} else {
			obj.setAttribute(eventType,func);
		}
	},
	isIE: (document.documentElement.getAttribute("style") == document.documentElement.style)
}
var changeImage ={
	attach: function(){
		var preloadImg = new Object();
		var preNum = 0;
		var images = document.getElementsByTagName('img');
		for(var i = 0,num = images.length;i < num; i++){
			var img = images[i];
			var imgSrc = img.src;
			if(imgSrc.indexOf('_f.') > -1 && img.parentNode.href){
				var newImgSrc = imgSrc.split('_f.')[0] + '_h.' + imgSrc.split('_f.')[1];
				preloadImg[preNum] = new Image();
				preloadImg[preNum].src = newImgSrc;
				var funcOnImg = 'changeImage.action(this,\'' + newImgSrc + '\')\;return false\;';
				var funcOutImg = 'changeImage.action(this,\'' + imgSrc + '\')\;return false\;';
				util.setEvent(img.parentNode,'onmouseover',funcOnImg);
				util.setEvent(img.parentNode,'onmouseout',funcOutImg);
				preNum++;
			}
		}
	},
	action: function(eventAnchor,imgSrc){
		eventAnchor.getElementsByTagName('img')[0].src = imgSrc;
	}
}
window.onload = function(){
	changeImage.attach();
}