​

var is  = false;

​

function isPortrait(src) {

    var img = new Image();

    img.src = src;

   var  here = img.onload = function() {

​

        alert(img.width+"x"+img.height);

        if(img.height>img.width)

        {

            is = true;

          alert(is + "9");

        }

      // it is here at this moment where you can get result of the 

     // awaited async function onload() 

     document.getElementById("heading").innerHTML = "is it Portrait ? " + is;

    };

}

​

​

 isPortrait("http://blogs.smithsonianmag.com/aroundthemall/files/2009/01/npg_portraits_nicholson_jack_2002-244x300.jpg");

​

​

​