function changeBGImage(id,url){
	if(document.getElementById(id)){
		obj = document.getElementById(id);
		obj.style.backgroundImage="url("+url+")";
	}
	return true;
}
function changeSrcImage(pid,id,url){
	if(document.getElementById(id)){
		if(document.getElementById('cur_bigimage_id').value!=pid){
			obj = document.getElementById(id);
			obj.src=url;
		}
	}
	return true;
}

function preload(id,url){
	if(document.images){
		var length=imgArr.length;
		imgArr[id]=new Image
		imgArr[id].src=url;
	}
}