 B x N x 2
        </ul>
        Outputs
        <ul>
            <li> List of targets.
        </ul>
        <p>Override this function to change how labels are converted into targets. You can use PoseTools.create_label_images to generate the target heatmaps. You can use PoseTools.create_affinity_labels to generate the target part affinity field heatmaps.</p>

        <p>Both the inputs and outputs are numpy arrays. This function will be injected into tensorflow dataset pipeline using tf.dataset.map.</p>

 