window.onload = function(){
    if(document.getElementById("c_canvas1")){
        var ctx1 = document.getElementById("c_canvas1").getContext('2d');
    }
    if(document.getElementById("c_canvas2")){
        var ctx2 = document.getElementById("c_canvas2").getContext('2d');
    }
    var ctx = ctx1||ctx2;
    var img = new Image();
    var speed = 120;
    img.onload = function(){
        function drawStar(){
            for(var i = 0; i < 4; i++ ){
                draw(i);
            }
            function draw(x){
                setTimeout(function(){
                     ctx.clearRect(0,0,270,270);
                     ctx.drawImage(img,0,270*x,270,270,0,0,270,270);
                },speed*x);
            }
        }
        setInterval(drawStar,480);
    }
    if( ctx == ctx1){
        ctx = ctx1;
        img.src = 'themes/images/imgc/an1.png';
    }
    if( ctx == ctx2){
        ctx = ctx2;
        img.src = 'themes/images/imgc/an2.png';
    }
}