import tensorflow as tf

                tf.float32, shape=(None, None, None, 4))
            self._scores = tf.placeholder(
                tf.float32, shape=(None, None, self._num_classes))

            self._boxes_predi, self._scores_predi, self._classes_predi,\
                self._valid_detections_predi = \
                tf.image.combined_non_max_suppression(
                    boxes=self._boxes, scores=self._scores,
                    max_output_size_per_class=50, max_total_size=50,
                    iou_threshold=0.45, score_threshold=self._score_threshold)

            self._label_map = self._load_labelmap(self._label_file)
