Source code for albumentations.core.transforms_interface

import random

import cv2

__all__ = ['to_tuple', 'BasicTransform', 'DualTransform', 'ImageOnlyTransform', 'NoOp']

[docs]def to_tuple(param, low=None, bias=None): """Convert input argument to min-max tuple Args: param (scalar, tuple or list of 2+ elements): Input value. If value is scalar, return value would be (offset - value, offset + value). If value is tuple, return value would be value + offset (broadcasted). low: Second element of tuple can be passed as optional argument bias: An offset factor added to each element """ if low is not None and bias is not None: raise ValueError('Arguments low and bias are mutually exclusive') if param is None: return param if isinstance(param, (int, float)): if low is None: param = - param, + param else: param = (low, param) if low < param else (param, low) elif isinstance(param, (list, tuple)): param = tuple(param) else: raise ValueError('Argument param must be either scalar (int,float) or tuple') if bias is not None: return tuple([bias + x for x in param]) return tuple(param)
class BasicTransform(object): def __init__(self, always_apply=False, p=0.5): self.p = p self.always_apply = always_apply self._additional_targets = {} def __call__(self, force_apply=False, **kwargs): if (random.random() < self.p) or self.always_apply or force_apply: params = self.get_params() params = self.update_params(params, **kwargs) if self.targets_as_params: targets_as_params = {k: kwargs[k] for k in self.targets_as_params} params_dependent_on_targets = self.get_params_dependent_on_targets(targets_as_params) params.update(params_dependent_on_targets) res = {} for key, arg in kwargs.items(): if arg is not None: target_function = self._get_target_function(key) target_dependencies = {k: kwargs[k] for k in self.target_dependence.get(key, [])} res[key] = target_function(arg, **dict(params, **target_dependencies)) else: res[key] = None return res return kwargs def _get_target_function(self, key): transform_key = key if key in self._additional_targets: transform_key = self._additional_targets.get(key, None) target_function = self.targets.get(transform_key, lambda x, **p: x) return target_function def apply(self, img, **params): raise NotImplementedError def get_params(self): return {} @property def targets(self): # you must specify targets in subclass # for example: ('image', 'mask') # ('image', 'boxes') raise NotImplementedError def update_params(self, params, **kwargs): if hasattr(self, 'interpolation'): params['interpolation'] = self.interpolation params.update({'cols': kwargs['image'].shape[1], 'rows': kwargs['image'].shape[0]}) return params @property def target_dependence(self): return {} def add_targets(self, additional_targets): """Add targets to transform them the same way as one of existing targets ex: {'target_image': 'image'} ex: {'obj1_mask': 'mask', 'obj2_mask': 'mask'} by the way you must have at least one object with key 'image' Args: additional_targets (dict): keys - new target name, values - old target name. ex: {'image2': 'image'} """ self._additional_targets = additional_targets @property def targets_as_params(self): return [] def get_params_dependent_on_targets(self, params): raise NotImplementedError('Method get_params_dependent_on_targets is not implemented in class ' + self.__class__.__name__)
[docs]class DualTransform(BasicTransform): """Transform for segmentation task.""" @property def targets(self): return {'image': self.apply, 'mask': self.apply_to_mask, 'masks': self.apply_to_masks, 'bboxes': self.apply_to_bboxes, 'keypoints': self.apply_to_keypoints} def apply_to_bbox(self, bbox, **params): raise NotImplementedError('Method apply_to_bbox is not implemented in class ' + self.__class__.__name__) def apply_to_keypoint(self, keypoint, **params): raise NotImplementedError('Method apply_to_keypoint is not implemented in class ' + self.__class__.__name__) def apply_to_bboxes(self, bboxes, **params): bboxes = [list(bbox) for bbox in bboxes] return [self.apply_to_bbox(bbox[:4], **params) + bbox[4:] for bbox in bboxes] def apply_to_keypoints(self, keypoints, **params): keypoints = [list(keypoint) for keypoint in keypoints] return [self.apply_to_keypoint(keypoint[:4], **params) + keypoint[4:] for keypoint in keypoints] def apply_to_mask(self, img, **params): return self.apply(img, **{k: cv2.INTER_NEAREST if k == 'interpolation' else v for k, v in params.items()}) def apply_to_masks(self, masks, **params): return [self.apply_to_mask(mask, **params) for mask in masks]
[docs]class ImageOnlyTransform(BasicTransform): """Transform applied to image only.""" @property def targets(self): return {'image': self.apply}
[docs]class NoOp(DualTransform): """Does nothing""" def apply_to_keypoint(self, keypoint, **params): return keypoint def apply_to_bbox(self, bbox, **params): return bbox def apply(self, img, **params): return img def apply_to_mask(self, img, **params): return img