def ProcessOutputs(self, input_batch, model_outputs):
    """Produce additional decoder outputs for WaymoOpenDataset.

    Args:
      input_batch: A .NestedMap of the inputs to the model.
      model_outputs: A .NestedMap of the outputs of the model, including::
        - per_class_predicted_bboxes: [batch, num_classes, num_boxes, 7] float
          Tensor with per class 3D (7 DOF) bounding boxes.
        - per_class_predicted_bbox_scores: [batch, num_classes, num_boxes] float
          Tensor with per class, per box scores.
        - per_class_valid_mask: [batch, num_classes, num_boxes] masking Tensor
          indicating which boxes were still kept after NMS for each class.

    Returns:
      A NestedMap of additional decoder outputs needed for
      PostProcessDecodeOut.
    """
    del model_outputs
    p = self.params
    input_labels = input_batch.labels
    input_metadata = input_batch.metadata
    source_ids = tf.strings.join([
        input_metadata.run_segment,
        tf.as_string(input_metadata.run_start_offset)
    ],
                                 separator='_')
    ret = py_utils.NestedMap({
        'num_points_in_bboxes': input_batch.labels.bboxes_3d_num_points,
        # Ground truth.
        'bboxes_3d': input_labels.bboxes_3d,
        'bboxes_3d_mask': input_labels.bboxes_3d_mask,
        'labels': input_labels.labels,
        'label_ids': input_labels.label_ids,
        'speed': input_labels.speed,
        'acceleration': input_labels.acceleration,
        # Fill the following in.
        'source_ids': source_ids,
        'difficulties': input_labels.single_frame_detection_difficulties,
        'unfiltered_bboxes_3d_mask': input_labels.unfiltered_bboxes_3d_mask,
        'run_segment': input_metadata.run_segment,
        'run_start_offset': input_metadata.run_start_offset,
        'pose': input_metadata.pose,
    })
    if p.draw_visualizations:
      laser_sample = self._SampleLaserForVisualization(
          input_batch.lasers.points_xyz, input_batch.lasers.points_padding)
      ret.update(laser_sample)
    return ret