get_images() keep returning false

[Mari Muthu]

require_once 'nanodicom.php';

$filename =__DIR__.'/samples/CT_small.dcm';

if (!file_exists($filename)) {

echo "File not found !";

die();

}

$dicom  = Nanodicom::factory($filename, 'pixeler');

$images = $dicom->get_images();

if($images === FALSE){

echo "dome error found !";

}

this is test.php . get_images() continously returning false only.