/public/js/redactor/image_upload.php

<?php
 
// This is a simplified example, which doesn't cover security of uploaded images. 
// This example just demonstrate the logic behind the process. 
 
 
// files storage folder

$dir = "../../files/";
 
$_FILES['file']['type'] = strtolower($_FILES['file']['type']);
 
if ($_FILES['file']['type'] == 'image/png' 
|| $_FILES['file']['type'] == 'image/jpg' 
|| $_FILES['file']['type'] == 'image/gif' 
|| $_FILES['file']['type'] == 'image/jpeg'
|| $_FILES['file']['type'] == 'image/pjpeg')
{	
    // setting file's mysterious name
    $file = $dir.md5(date('YmdHis')).'.jpg';

    // copying
    copy($_FILES['file']['tmp_name'], $file);

    $file = "/files/".md5(date('YmdHis')).'.jpg';
    // displaying file    
	$array = array(
		'filelink' => $file
	);
	
	echo stripslashes(json_encode($array));   
    
}
 
?>