if(file_exists($myfile))
{
    // Add bellow code for mime type
$temp = explode(".",$myfile);
$ext = strtolower(end($temp));
$mime_types = array(

        // video
        '3gp' => 'video/3gpp',
        '3g2' => 'video/3g2',
        'avi' => 'video/avi',
        'mp4' => 'video/mp4',
        'asf' => 'video/asf',
        'mov' => 'video/quicktime',
    );
if (array_key_exists($ext, $mime_types)){
   $mm_type=$mime_types[$ext];
}else{
   $mm_type="application/octet-stream";
}
$fname=str_replace(" ","_",$result->TITLE);
//header("Cache-Control: public, must-revalidate");
header("Pragma: public");

header("Content-Type: ".$mm_type);

header('Content-Disposition: attachment; filename='.$fname);
header('Content-Length: '.filesize($myfile));
header("Content-Transfer-Encoding: binary");
ob_clean();
flush();
readfile($myfile);
}
else
{
    echo "unable to download";

}