public function annotateBatch(array $images, array $options = [])
    {
        $this->validateBatch($images, Image::class);

        $requests = [];
        foreach ($images as $image) {
            $requests[] = $image->requestObject();
        }

        $res = $this->connection->annotate([
            'requests' => $requests
        ] + $options);

        $annotations = [];
        if (isset($res['responses'])) {
            foreach ($res['responses'] as $response) {
                $annotations[] = new Annotation($response);
            }
        }

        return $annotations;
    }