Converting data:image base64 to blob in this code

I'd like to change the URLs from data:image base64 to blob. This is the original code that produces the base64 urls:

<script>

    $(window).load(function(){

    function readURL() {
        var $input = $(this);
        var $newinput =  $(this).parent().parent().parent().find('.portimg ');
        if (this.files && this.files[0]) {
            var reader = new FileReader();
            reader.onload = function (e) {
                reset($newinput.next('.delbtn'), true);
                $newinput.attr('src', e.target.result).show();
                $newinput.after('<div class="delbtn delete_upload"  title="Remove"><span class="bbb-icon bbb-i-remove2"></span></div>');


$("form").on('click', '.delbtn', function (e) {
    reset($(this));
    $("form").find('#rright-<?php echo $i;?>').hide();
  });
            }
            reader.readAsDataURL(this.files[0]);
        }
    }
    $(".file").change(readURL);


    function reset(elm, prserveFileName) {
        if (elm && elm.length > 0) {
            var $input = elm;
            $input.prev('.portimg').attr('src', '').hide();

            if (!prserveFileName) {
                $($input).parent().parent().parent().find('input.file ').val("");
                //input.fileUpload and input#uploadre both need to empty values for particular div
            }
            elm.remove();
        }
    }

    });

  </script>

What I want is to call Object.createObjectURL(this.files[0]) to get the object URL, and use that as the src of your img; (just don't even bother with the FileReader).