window.addEventListener?window.addEventListener("load",begin,false):window.attachEvent("onload",begin);

imgs = new Array(), now=0, nIndex=0, opacNow=10;

function begin() {
    imgs = document.getElementById("pic_dia").getElementsByTagName("img");

    for(i=1; i<imgs.length; i++)
        imgs[i].style.opacity = 0;

    imgs[now].style.display = "block";
    imgs[now].style.opacity = 1;
    setTimeout(fade_out,3000);
}

function fade_in() {
    if (opacNow >= 10) {
        opacNow = 10;
        setTimeout(fade_out,5000);
    } else {
        opacNow += 1;
        setOpacity(opacNow);
        setTimeout(fade_in,20);
    }
}


function fade_out() {
    if (opacNow <= 0) {
        opacNow = 0;
        imgs[now].style.display = "none";
        nIndex = imgs[now+1]?now+1:0;
        now = nIndex;
        imgs[now].style.display = "block";
        setTimeout(fade_in,50);
    } else {
        opacNow -= 1;
        setOpacity(opacNow);
        setTimeout(fade_out,20);
    }
}


function setOpacity(value) {
    imgs[now].style.opacity = value/10;
    imgs[now].style.filter = 'alpha(opacity=' + value*10 + ')';
}