html2canvas for map

gistfile1.txt

function convertasbinaryimage() {
    html2canvas(document.getElementById("map"), {
        useCORS: true,
        onrendered: function (canvas) {
            var img = canvas.toDataURL("image/png");
            img = img.replace('data:image/png;base64,', '');
            var finalImageSrc = 'data:image/png;base64,' + img;
            $('#googlemapbinary').attr('src', finalImageSrc);
         }
    });
}