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Source code for mmaction.datasets.transforms.wrappers

# Copyright (c) OpenMMLab. All rights reserved.
import random

import mmengine
import numpy as np
from mmcv.transforms import BaseTransform, to_tensor
from mmengine.utils import digit_version

from mmaction.registry import TRANSFORMS


[docs]@TRANSFORMS.register_module() class TorchVisionWrapper(BaseTransform): """Torchvision Augmentations, under torchvision.transforms. Args: op (str): The name of the torchvision transformation. """ def __init__(self, op, **kwargs): try: import torchvision import torchvision.transforms as tv_trans except ImportError: raise RuntimeError('Install torchvision to use TorchvisionTrans') if digit_version(torchvision.__version__) < digit_version('0.8.0'): raise RuntimeError('The version of torchvision should be at least ' '0.8.0') trans = getattr(tv_trans, op, None) assert trans, f'Transform {op} not in torchvision' self.trans = trans(**kwargs)
[docs] def transform(self, results): """Perform Torchvision augmentations. Args: results (dict): The resulting dict to be modified and passed to the next transform in pipeline. """ assert 'imgs' in results imgs = [x.transpose(2, 0, 1) for x in results['imgs']] imgs = to_tensor(np.stack(imgs)) imgs = self.trans(imgs).data.numpy() imgs[imgs > 255] = 255 imgs[imgs < 0] = 0 imgs = imgs.astype(np.uint8) imgs = [x.transpose(1, 2, 0) for x in imgs] results['imgs'] = imgs return results
[docs]@TRANSFORMS.register_module() class PytorchVideoWrapper(BaseTransform): """PytorchVideoTrans Augmentations, under pytorchvideo.transforms. Args: op (str): The name of the pytorchvideo transformation. """ def __init__(self, op, **kwargs): try: import pytorchvideo.transforms as ptv_trans import torch except ImportError: raise RuntimeError('Install pytorchvideo to use PytorchVideoTrans') if digit_version(torch.__version__) < digit_version('1.8.0'): raise RuntimeError( 'The version of PyTorch should be at least 1.8.0') trans = getattr(ptv_trans, op, None) assert trans, f'Transform {op} not in pytorchvideo' supported_pytorchvideo_trans = ('AugMix', 'RandAugment', 'RandomResizedCrop', 'ShortSideScale', 'RandomShortSideScale') assert op in supported_pytorchvideo_trans,\ f'PytorchVideo Transform {op} is not supported in MMAction2' self.trans = trans(**kwargs) self.op = op
[docs] def transform(self, results): """Perform PytorchVideoTrans augmentations. Args: results (dict): The resulting dict to be modified and passed to the next transform in pipeline. """ assert 'imgs' in results assert 'gt_bboxes' not in results,\ f'PytorchVideo {self.op} doesn\'t support bboxes yet.' assert 'proposals' not in results,\ f'PytorchVideo {self.op} doesn\'t support bboxes yet.' if self.op in ('AugMix', 'RandAugment'): # list[ndarray(h, w, 3)] -> torch.tensor(t, c, h, w) imgs = [x.transpose(2, 0, 1) for x in results['imgs']] imgs = to_tensor(np.stack(imgs)) else: # list[ndarray(h, w, 3)] -> torch.tensor(c, t, h, w) # uint8 -> float32 imgs = to_tensor((np.stack(results['imgs']).transpose(3, 0, 1, 2) / 255.).astype(np.float32)) imgs = self.trans(imgs).data.numpy() if self.op in ('AugMix', 'RandAugment'): imgs[imgs > 255] = 255 imgs[imgs < 0] = 0 imgs = imgs.astype(np.uint8) # torch.tensor(t, c, h, w) -> list[ndarray(h, w, 3)] imgs = [x.transpose(1, 2, 0) for x in imgs] else: # float32 -> uint8 imgs = imgs * 255 imgs[imgs > 255] = 255 imgs[imgs < 0] = 0 imgs = imgs.astype(np.uint8) # torch.tensor(c, t, h, w) -> list[ndarray(h, w, 3)] imgs = [x for x in imgs.transpose(1, 2, 3, 0)] results['imgs'] = imgs return results
[docs]@TRANSFORMS.register_module() class ImgAug(BaseTransform): """Imgaug augmentation. Adds custom transformations from imgaug library. Please visit `https://imgaug.readthedocs.io/en/latest/index.html` to get more information. Two demo configs could be found in tsn and i3d config folder. It's better to use uint8 images as inputs since imgaug works best with numpy dtype uint8 and isn't well tested with other dtypes. It should be noted that not all of the augmenters have the same input and output dtype, which may cause unexpected results. Required keys are "imgs", "img_shape"(if "gt_bboxes" is not None) and "modality", added or modified keys are "imgs", "img_shape", "gt_bboxes" and "proposals". It is worth mentioning that `Imgaug` will NOT create custom keys like "interpolation", "crop_bbox", "flip_direction", etc. So when using `Imgaug` along with other mmaction2 pipelines, we should pay more attention to required keys. Two steps to use `Imgaug` pipeline: 1. Create initialization parameter `transforms`. There are three ways to create `transforms`. 1) string: only support `default` for now. e.g. `transforms='default'` 2) list[dict]: create a list of augmenters by a list of dicts, each dict corresponds to one augmenter. Every dict MUST contain a key named `type`. `type` should be a string(iaa.Augmenter's name) or an iaa.Augmenter subclass. e.g. `transforms=[dict(type='Rotate', rotate=(-20, 20))]` e.g. `transforms=[dict(type=iaa.Rotate, rotate=(-20, 20))]` 3) iaa.Augmenter: create an imgaug.Augmenter object. e.g. `transforms=iaa.Rotate(rotate=(-20, 20))` 2. Add `Imgaug` in dataset pipeline. It is recommended to insert imgaug pipeline before `Normalize`. A demo pipeline is listed as follows. ``` pipeline = [ dict( type='SampleFrames', clip_len=1, frame_interval=1, num_clips=16, ), dict(type='RawFrameDecode'), dict(type='Resize', scale=(-1, 256)), dict( type='MultiScaleCrop', input_size=224, scales=(1, 0.875, 0.75, 0.66), random_crop=False, max_wh_scale_gap=1, num_fixed_crops=13), dict(type='Resize', scale=(224, 224), keep_ratio=False), dict(type='Flip', flip_ratio=0.5), dict(type='Imgaug', transforms='default'), # dict(type='Imgaug', transforms=[ # dict(type='Rotate', rotate=(-20, 20)) # ]), dict(type='Normalize', **img_norm_cfg), dict(type='FormatShape', input_format='NCHW'), dict(type='Collect', keys=['imgs', 'label'], meta_keys=[]), dict(type='ToTensor', keys=['imgs', 'label']) ] ``` Args: transforms (str | list[dict] | :obj:`iaa.Augmenter`): Three different ways to create imgaug augmenter. """ def __init__(self, transforms): # Hack to fix incompatibility of ImgAug and latest Numpy if digit_version(np.__version__) >= digit_version('1.24.0'): np.bool = bool import imgaug.augmenters as iaa if transforms == 'default': self.transforms = self.default_transforms() elif isinstance(transforms, list): assert all(isinstance(trans, dict) for trans in transforms) self.transforms = transforms elif isinstance(transforms, iaa.Augmenter): self.aug = self.transforms = transforms else: raise ValueError('transforms must be `default` or a list of dicts' ' or iaa.Augmenter object') if not isinstance(transforms, iaa.Augmenter): self.aug = iaa.Sequential( [self.imgaug_builder(t) for t in self.transforms])
[docs] @staticmethod def default_transforms(): """Default transforms for imgaug. Implement RandAugment by imgaug. Please visit `https://arxiv.org/abs/1909.13719` for more information. Augmenters and hyper parameters are borrowed from the following repo: https://github.com/tensorflow/tpu/blob/master/models/official/efficientnet/autoaugment.py # noqa Miss one augmenter ``SolarizeAdd`` since imgaug doesn't support this. Returns: dict: The constructed RandAugment transforms. """ # RandAugment hyper params num_augmenters = 2 cur_magnitude, max_magnitude = 9, 10 cur_level = 1.0 * cur_magnitude / max_magnitude return [ dict( type='SomeOf', n=num_augmenters, children=[ dict( type='ShearX', shear=17.19 * cur_level * random.choice([-1, 1])), dict( type='ShearY', shear=17.19 * cur_level * random.choice([-1, 1])), dict( type='TranslateX', percent=.2 * cur_level * random.choice([-1, 1])), dict( type='TranslateY', percent=.2 * cur_level * random.choice([-1, 1])), dict( type='Rotate', rotate=30 * cur_level * random.choice([-1, 1])), dict(type='Posterize', nb_bits=max(1, int(4 * cur_level))), dict(type='Solarize', threshold=256 * cur_level), dict(type='EnhanceColor', factor=1.8 * cur_level + .1), dict(type='EnhanceContrast', factor=1.8 * cur_level + .1), dict( type='EnhanceBrightness', factor=1.8 * cur_level + .1), dict(type='EnhanceSharpness', factor=1.8 * cur_level + .1), dict(type='Autocontrast', cutoff=0), dict(type='Equalize'), dict(type='Invert', p=1.), dict( type='Cutout', nb_iterations=1, size=0.2 * cur_level, squared=True) ]) ]
[docs] def imgaug_builder(self, cfg): """Import a module from imgaug. It follows the logic of :func:`build_from_cfg`. Use a dict object to create an iaa.Augmenter object. Args: cfg (dict): Config dict. It should at least contain the key "type". Returns: obj:`iaa.Augmenter`: The constructed imgaug augmenter. """ import imgaug.augmenters as iaa assert isinstance(cfg, dict) and 'type' in cfg args = cfg.copy() obj_type = args.pop('type') if mmengine.is_str(obj_type): obj_cls = getattr(iaa, obj_type) if hasattr(iaa, obj_type) \ else getattr(iaa.pillike, obj_type) elif issubclass(obj_type, iaa.Augmenter): obj_cls = obj_type else: raise TypeError( f'type must be a str or valid type, but got {type(obj_type)}') for aug_list_key in ['children', 'then_list', 'else_list']: if aug_list_key in args: args[aug_list_key] = [ self.imgaug_builder(child) for child in args[aug_list_key] ] return obj_cls(**args)
def __repr__(self): repr_str = self.__class__.__name__ + f'(transforms={self.aug})' return repr_str
[docs] def transform(self, results): """Perform Imgaug augmentations. Args: results (dict): The resulting dict to be modified and passed to the next transform in pipeline. """ assert results['modality'] == 'RGB', 'Imgaug only support RGB images.' in_type = results['imgs'][0].dtype cur_aug = self.aug.to_deterministic() results['imgs'] = [ cur_aug.augment_image(frame) for frame in results['imgs'] ] img_h, img_w, _ = results['imgs'][0].shape out_type = results['imgs'][0].dtype assert in_type == out_type, \ ('Imgaug input dtype and output dtype are not the same. ', f'Convert from {in_type} to {out_type}') if 'gt_bboxes' in results: from imgaug.augmentables import bbs bbox_list = [ bbs.BoundingBox( x1=bbox[0], y1=bbox[1], x2=bbox[2], y2=bbox[3]) for bbox in results['gt_bboxes'] ] bboxes = bbs.BoundingBoxesOnImage( bbox_list, shape=results['img_shape']) bbox_aug, *_ = cur_aug.augment_bounding_boxes([bboxes]) results['gt_bboxes'] = [[ max(bbox.x1, 0), max(bbox.y1, 0), min(bbox.x2, img_w), min(bbox.y2, img_h) ] for bbox in bbox_aug.items] if 'proposals' in results: bbox_list = [ bbs.BoundingBox( x1=bbox[0], y1=bbox[1], x2=bbox[2], y2=bbox[3]) for bbox in results['proposals'] ] bboxes = bbs.BoundingBoxesOnImage( bbox_list, shape=results['img_shape']) bbox_aug, *_ = cur_aug.augment_bounding_boxes([bboxes]) results['proposals'] = [[ max(bbox.x1, 0), max(bbox.y1, 0), min(bbox.x2, img_w), min(bbox.y2, img_h) ] for bbox in bbox_aug.items] results['img_shape'] = (img_h, img_w) return results