public function reverseTransform($fID)
    {
        if (!is_numeric($fID) || $fID == 0) {
            return null;
        }

        $rep = $this->entityManager->getRepository('Concrete\Core\File\File');

        $f = $rep->find($fID);
        if (!is_object($f) || $f->isError()) {
            throw new TransformationFailedException('Invalid file ID.');
        }

        return $f;
    }