Edit in JSFiddle

var xhr = new XMLHttpRequest(); 
xhr.open("GET", "/favicon.png"); 
//although we can get the remote data directly into an arraybuffer using the string "arraybuffer" assigned to responseType property. For the sake of example we are putting it into a blob and then copying the blob data into an arraybuffer.
xhr.responseType = "blob";

function analyze_data(blob)
    var myReader = new FileReader();
    myReader.addEventListener("loadend", function(e)
        var buffer = e.srcElement.result;//arraybuffer object

xhr.onload = function()