@@ -42,6 +42,15 @@ class MultiScaleFlipAug(object):
                 'flip has no effect when RandomFlip is not in transforms')
 
     def __call__(self, results):
+        """Call function to apply time time augment transforms on results.
+
+        Args:
+            results (dict): Result dict contains the data to transform.
+
+        Returns:
+           dict: The augmented data, where each value is wrapped into a list.
+        """
+
         aug_data = []
         flip_aug = [False, True] if self.flip else [False]
         for scale in self.img_scale:
import warnings

import mmcv

from ..builder import PIPELINES
from .compose import Compose


@PIPELINES.register_module()
class MultiScaleFlipAug(object):
    """Test-time augmentation with multiple scales and flipping

    Args:
        transforms (list[dict]): Transforms to apply in each augmentation.
        img_scale (tuple | list[tuple]: Images scales for resizing.
        flip (bool): Whether apply flip augmentation. Default: False.
        flip_direction (str | list[str]): Flip augmentation directions,
            options are "horizontal" and "vertical". If flip_direction is list,
            multiple flip augmentations will be applied.
            It has no effect when flip == False. Default: "horizontal".
    """

    def __init__(self,
                 transforms,
                 img_scale,
                 flip=False,
                 flip_direction='horizontal'):
        self.transforms = Compose(transforms)
        self.img_scale = img_scale if isinstance(img_scale,
                                                 list) else [img_scale]
        assert mmcv.is_list_of(self.img_scale, tuple)
        self.flip = flip
        self.flip_direction = flip_direction if isinstance(
            flip_direction, list) else [flip_direction]
        assert mmcv.is_list_of(self.flip_direction, str)
        if not self.flip and self.flip_direction != ['horizontal']:
            warnings.warn(
                'flip_direction has no effect when flip is set to False')
        if (self.flip
                and not any([t['type'] == 'RandomFlip' for t in transforms])):
            warnings.warn(
                'flip has no effect when RandomFlip is not in transforms')

    def __call__(self, results):
        aug_data = []
        flip_aug = [False, True] if self.flip else [False]
        for scale in self.img_scale:
            for flip in flip_aug:
                for direction in self.flip_direction:
                    _results = results.copy()
                    _results['scale'] = scale
                    _results['flip'] = flip
                    _results['flip_direction'] = direction
                    data = self.transforms(_results)
                    aug_data.append(data)
        # list of dict to dict of list
        aug_data_dict = {key: [] for key in aug_data[0]}
        for data in aug_data:
            for key, val in data.items():
                aug_data_dict[key].append(val)
        return aug_data_dict

    def __repr__(self):
        repr_str = self.__class__.__name__
        repr_str += f'(transforms={self.transforms}, '
        repr_str += f'img_scale={self.img_scale}, flip={self.flip})'
        repr_str += f'flip_direction={self.flip_direction}'
        return repr_str

Give an example in the class docstring.