function resizeImage(max, imageID, from) {
    //指定欲改變大小的圖檔位置
    var name = document.getElementById(imageID);
    //改變大小
    var scale = max / name.width;
    if (name.height > name.width)
        scale = max / name.height;
    //只要width調height就會調
    name.width = name.width * scale;
}

function changeImg(mypic, max) {
    //改變大小
    var scale = max / mypic.width;
    if (mypic.height > mypic.width)
        scale = max / mypic.height;
    //只要width調height就會調
    mypic.width = mypic.width * scale;
}