Retrieve an image from the server using asp classic

i found this code to read image through ajax, can anyone please tell how to do it with asp classic instead of php?

function LoadImg(filename) {
var xmlhttp;
if (window.XMLHttpRequest) { // code for IE7+, Firefox, Chrome, Opera, Safari
    xmlhttp = new XMLHttpRequest();
} else { // code for IE6, IE5
    xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange = function() {
    if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {     
        document.getElementById("documentHolder").src = "data:image/png;base64," + xmlhttp.responseText;
    }
};    
xmlhttp.open("GET", 'load.php?LoadImg='+filename );
xmlhttp.send(null);
}  

<?php
 if (isset($_GET['LoadImg'])) {
  header("Content-Type: image/png");
  $file = file_get_contents($_GET['LoadImg']);
  echo base64_encode($file);
}
?>