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| 1 | +# encoding: utf-8 |
| 2 | +""" |
| 3 | +Read images and corresponding labels. |
| 4 | +""" |
| 5 | + |
| 6 | +import torch |
| 7 | +from torch.utils.data import Dataset |
| 8 | +from torchvision import transforms |
| 9 | +import pandas as pd |
| 10 | +import numpy as np |
| 11 | +from PIL import Image |
| 12 | +import os |
| 13 | + |
| 14 | +from PIL import ImageFile |
| 15 | +ImageFile.LOAD_TRUNCATED_IMAGES = True |
| 16 | + |
| 17 | +############################################################# |
| 18 | +##### Dataset with memory bank and contrastive samples. ##### |
| 19 | +############################################################# |
| 20 | + |
| 21 | + |
| 22 | +class ISIC_InstanceSample(Dataset): |
| 23 | + |
| 24 | + def __init__(self, root_dir, csv_file, CCD_mode, transform=None, p=10, k=4096, |
| 25 | + mode='exact', is_sample=True, percent=1.0): |
| 26 | + super(ISIC_InstanceSample, self).__init__() |
| 27 | + |
| 28 | + self.p = p |
| 29 | + self.k = k |
| 30 | + self.mode = mode |
| 31 | + self.CCD_mode = CCD_mode |
| 32 | + self.is_sample = is_sample |
| 33 | + |
| 34 | + file = pd.read_csv(csv_file) |
| 35 | + |
| 36 | + self.root_dir = root_dir |
| 37 | + self.images = file['id_code'].values # image name |
| 38 | + self.labels = file['diagnosis'].values.astype(int) # scalar label |
| 39 | + n_classes = len(np.unique(self.labels)) |
| 40 | + # one hot. [num_images, num_classes] |
| 41 | + self.labels = np.eye(n_classes)[self.labels.reshape(-1)] |
| 42 | + self.transform = transform |
| 43 | + |
| 44 | + print('Total # images:{}, labels:{}'.format( |
| 45 | + len(self.images), len(self.labels))) |
| 46 | + |
| 47 | + num_samples = len(self.images) |
| 48 | + label = np.argmax(self.labels, axis=1) |
| 49 | + |
| 50 | + self.cls_positive = [[] for i in range(n_classes)] |
| 51 | + for i in range(num_samples): |
| 52 | + self.cls_positive[label[i]].append(i) |
| 53 | + |
| 54 | + self.cls_negative = [[] for i in range(n_classes)] |
| 55 | + for i in range(n_classes): |
| 56 | + for j in range(n_classes): |
| 57 | + if j == i: |
| 58 | + continue |
| 59 | + self.cls_negative[i].extend(self.cls_positive[j]) |
| 60 | + |
| 61 | + self.cls_positive = [np.asarray(self.cls_positive[i]) |
| 62 | + for i in range(n_classes)] |
| 63 | + self.cls_negative = [np.asarray(self.cls_negative[i]) |
| 64 | + for i in range(n_classes)] |
| 65 | + |
| 66 | + self.class_index = self.cls_positive |
| 67 | + |
| 68 | + if 0 < percent < 1: |
| 69 | + n = int(len(self.cls_negative[0]) * percent) |
| 70 | + self.cls_negative = [np.random.permutation(self.cls_negative[i])[0:n] |
| 71 | + for i in range(n_classes)] |
| 72 | + |
| 73 | + self.cls_positive = np.asarray(self.cls_positive, dtype=object) |
| 74 | + self.cls_negative = np.asarray(self.cls_negative, dtype=object) |
| 75 | + |
| 76 | + def __getitem__(self, index): |
| 77 | + image_name = os.path.join(self.root_dir, self.images[index]+'.png') |
| 78 | + img = Image.open(image_name).convert('RGB') |
| 79 | + target = np.argmax(self.labels, axis=1)[index] |
| 80 | + label = self.labels[index] |
| 81 | + |
| 82 | + if self.transform is not None: |
| 83 | + img = self.transform(img) |
| 84 | + |
| 85 | + if not self.is_sample: |
| 86 | + return img, target, index |
| 87 | + else: |
| 88 | + # sample contrastive examples |
| 89 | + if self.mode == 'exact': |
| 90 | + pos_idx = index |
| 91 | + elif self.mode == 'relax': |
| 92 | + pos_idx = np.random.choice(self.cls_positive[target], 1)[0] |
| 93 | + elif self.mode == 'multi_pos': |
| 94 | + pos_idx = np.random.choice( |
| 95 | + self.cls_positive[target], self.p, replace=False) |
| 96 | + else: |
| 97 | + raise NotImplementedError(self.mode) |
| 98 | + |
| 99 | + if self.CCD_mode == "sup": |
| 100 | + replace = True if self.k > len( |
| 101 | + self.cls_negative[target]) else False |
| 102 | + neg_idx = np.random.choice( |
| 103 | + self.cls_negative[target], self.k, replace=replace) |
| 104 | + elif self.CCD_mode == "unsup": |
| 105 | + pos_others = np.setdiff1d(self.cls_positive[target], ([index])) |
| 106 | + all_negative = np.hstack( |
| 107 | + (pos_others, self.cls_negative[target])) |
| 108 | + neg_idx = np.random.choice(all_negative, self.k, replace=True) |
| 109 | + |
| 110 | + if self.mode == 'exact' or self.mode == 'relax': |
| 111 | + sample_idx = np.hstack((np.asarray([pos_idx]), neg_idx)) |
| 112 | + elif self.mode == 'multi_pos': |
| 113 | + sample_idx = np.hstack((pos_idx, neg_idx)) |
| 114 | + |
| 115 | + return img, label, index, sample_idx |
| 116 | + |
| 117 | + def __len__(self): |
| 118 | + return len(self.images) |
| 119 | + |
| 120 | + |
| 121 | +def load_dataset(args, p=10, k=4096, mode='exact', is_sample=True, percent=1.0): |
| 122 | + csv_file_train = args.csv_file_path + \ |
| 123 | + args.dataset + '/' + args.split + '_train.csv' |
| 124 | + csv_file_test = args.csv_file_path + args.dataset + '/' + args.split + '_test.csv' |
| 125 | + |
| 126 | + train_transform = TransformTwice(transforms.Compose([ |
| 127 | + transforms.Resize((224, 224)), |
| 128 | + transforms.RandomAffine(degrees=10, translate=(0.02, 0.02)), |
| 129 | + transforms.RandomHorizontalFlip(), |
| 130 | + transforms.ToTensor(), |
| 131 | + transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225]), |
| 132 | + ])) |
| 133 | + |
| 134 | + test_transform = transforms.Compose([ |
| 135 | + transforms.Resize((224, 224)), |
| 136 | + transforms.ToTensor(), |
| 137 | + transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225]), |
| 138 | + ]) |
| 139 | + |
| 140 | + train_set = ISIC_InstanceSample(root_dir=args.root_path, |
| 141 | + csv_file=csv_file_train, |
| 142 | + CCD_mode=args.CCD_mode, |
| 143 | + transform=train_transform, |
| 144 | + p=p, |
| 145 | + k=k, |
| 146 | + mode=mode, |
| 147 | + is_sample=is_sample, |
| 148 | + percent=percent) |
| 149 | + |
| 150 | + test_set = ISIC_Dataset(root_dir=args.root_path, |
| 151 | + csv_file=csv_file_test, transform=test_transform) |
| 152 | + |
| 153 | + return train_set, test_set |
| 154 | + |
| 155 | + |
| 156 | +# Dataset without memory bank |
| 157 | +class ISIC_Dataset(Dataset): |
| 158 | + def __init__(self, root_dir, csv_file, transform=None): |
| 159 | + """ |
| 160 | + Args: |
| 161 | + data_dir: path to image directory. |
| 162 | + csv_file: path to the file containing images |
| 163 | + with corresponding labels. |
| 164 | + transform: optional transform to be applied on a sample. |
| 165 | + """ |
| 166 | + super(ISIC_Dataset, self).__init__() |
| 167 | + file = pd.read_csv(csv_file) |
| 168 | + |
| 169 | + self.root_dir = root_dir |
| 170 | + self.images = file['id_code'].values # image name |
| 171 | + self.labels = file['diagnosis'].values.astype(int) |
| 172 | + self.n_classes = len(np.unique(self.labels)) |
| 173 | + self.labels = np.eye(self.n_classes)[ |
| 174 | + self.labels.reshape(-1)] # one_hot labels |
| 175 | + self.transform = transform |
| 176 | + |
| 177 | + print('Total # images:{}, labels:{}'.format( |
| 178 | + len(self.images), len(self.labels))) |
| 179 | + |
| 180 | + def __getitem__(self, index): |
| 181 | + """ |
| 182 | + Args: |
| 183 | + index: the index of item |
| 184 | + Returns: |
| 185 | + image and its labels |
| 186 | + """ |
| 187 | + image_name = os.path.join(self.root_dir, self.images[index]+'.png') |
| 188 | + image = Image.open(image_name).convert('RGB') |
| 189 | + label = self.labels[index] |
| 190 | + if self.transform is not None: |
| 191 | + image = self.transform(image) |
| 192 | + |
| 193 | + return image, label |
| 194 | + |
| 195 | + def __len__(self): |
| 196 | + return len(self.images) |
| 197 | + |
| 198 | + |
| 199 | +class TransformTwice: |
| 200 | + def __init__(self, transform): |
| 201 | + self.transform = transform |
| 202 | + |
| 203 | + def __call__(self, inp): |
| 204 | + out1 = self.transform(inp) |
| 205 | + out2 = self.transform(inp) |
| 206 | + return out1, out2 |
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