サイトのfaviconを変更する - how to code something

<body onload="changeFavicon();">
<script>
function changeFavicon(){
  $('link[rel="shortcut icon"]').attr("href","http://2.bp.blogspot.com/_Q6gn7ObdMNM/TFZjwdIAICI/AAAAAAAAAEA/0FCC-oqq_3Q/s320/heart.gif");
 $('link[rel="apple-touch-icon"]').attr("href","http://2.bp.blogspot.com/_Q6gn7ObdMNM/TFZjwdIAICI/AAAAAAAAAEA/0FCC-oqq_3Q/s320/heart.gif");
};
</script>