from __future__ import print_function import os import os.path import numpy as np import random import pickle import json import math import torch import torch.utils.data as data import torchvision import torchvision.datasets as datasets import torchvision.transforms as transforms import torchnet as tnt import h5py from PIL import Image from PIL import ImageEnhance from pdb import set_trace as breakpoint # Set the appropriate paths of the datasets here. _MINI_IMAGENET_DATASET_DIR = './datasets/MiniImagenet' _IMAGENET_DATASET_DIR = './datasets/IMAGENET/ILSVRC2012' _IMAGENET_LOWSHOT_BENCHMARK_CATEGORY_SPLITS_PATH = './data/IMAGENET_LOWSHOT_BENCHMARK_CATEGORY_SPLITS.json' transformtypedict=dict( Brightness=ImageEnhance.Brightness, Contrast=ImageEnhance.Contrast, Sharpness=ImageEnhance.Sharpness, Color=ImageEnhance.Color ) def get_label_ids(class_to_idx, class_names, inside=True): label_ids = [] if inside: for cname in class_names: label_ids.append(class_to_idx[cname]) else: for cname, clabel in class_to_idx.items(): if cname not in class_names: label_ids.append(clabel) return label_ids class ImageJitter(object): def __init__(self, transformdict): self.transforms = [(transformtypedict[k], transformdict[k]) for k in transformdict] def __call__(self, img): out = img randtensor = torch.rand(len(self.transforms)) for i, (transformer, alpha) in enumerate(self.transforms): r = alpha*(randtensor[i]*2.0 -1.0) + 1 out = transformer(out).enhance(r).convert('RGB') return out class Denormalize(object): def __init__(self, mean, std): self.mean = mean self.std = std def __call__(self, tensor): for t, m, s in zip(tensor, self.mean, self.std): t.mul_(s).add_(m) return tensor def buildLabelIndex(labels): label2inds = {} for idx, label in enumerate(labels): if label not in label2inds: label2inds[label] = [] label2inds[label].append(idx) return label2inds def load_data(file): with open(file, 'rb') as fo: data = pickle.load(fo) return data class MiniImageNet(data.Dataset): def __init__(self, phase='train', do_not_use_random_transf=False): self.base_folder = 'miniImagenet' assert(phase=='train' or phase=='val' or phase=='test') self.phase = phase self.name = 'MiniImageNet_' + phase print('Loading mini ImageNet dataset - phase {0}'.format(phase)) file_train_categories_train_phase = os.path.join( _MINI_IMAGENET_DATASET_DIR, 'miniImageNet_category_split_train_phase_train.pickle') file_train_categories_val_phase = os.path.join( _MINI_IMAGENET_DATASET_DIR, 'miniImageNet_category_split_train_phase_val.pickle') file_train_categories_test_phase = os.path.join( _MINI_IMAGENET_DATASET_DIR, 'miniImageNet_category_split_train_phase_test.pickle') file_val_categories_val_phase = os.path.join( _MINI_IMAGENET_DATASET_DIR, 'miniImageNet_category_split_val.pickle') file_test_categories_test_phase = os.path.join( _MINI_IMAGENET_DATASET_DIR, 'miniImageNet_category_split_test.pickle') if self.phase=='train': # During training phase we only load the training phase images # of the training categories (aka base categories). data_train = load_data(file_train_categories_train_phase) self.data = data_train['data'] self.labels = data_train['labels'] self.label2ind = buildLabelIndex(self.labels) self.labelIds = sorted(self.label2ind.keys()) self.num_cats = len(self.labelIds) self.labelIds_base = self.labelIds self.num_cats_base = len(self.labelIds_base) elif self.phase=='val' or self.phase=='test': if self.phase=='test': # load data that will be used for evaluating the recognition # accuracy of the base categories. data_base = load_data(file_train_categories_test_phase) # load data that will be use for evaluating the few-shot recogniton # accuracy on the novel categories. data_novel = load_data(file_test_categories_test_phase) else: # phase=='val' # load data that will be used for evaluating the recognition # accuracy of the base categories. data_base = load_data(file_train_categories_val_phase) # load data that will be use for evaluating the few-shot recogniton # accuracy on the novel categories. data_novel = load_data(file_val_categories_val_phase) self.data = np.concatenate( [data_base['data'], data_novel['data']], axis=0) self.labels = data_base['labels'] + data_novel['labels'] self.label2ind = buildLabelIndex(self.labels) self.labelIds = sorted(self.label2ind.keys()) self.num_cats = len(self.labelIds) self.labelIds_base = buildLabelIndex(data_base['labels']).keys() self.labelIds_novel = buildLabelIndex(data_novel['labels']).keys() self.num_cats_base = len(self.labelIds_base) self.num_cats_novel = len(self.labelIds_novel) intersection = set(self.labelIds_base) & set(self.labelIds_novel) assert(len(intersection) == 0) else: raise ValueError('Not valid phase {0}'.format(self.phase)) mean_pix = [x/255.0 for x in [120.39586422, 115.59361427, 104.54012653]] std_pix = [x/255.0 for x in [70.68188272, 68.27635443, 72.54505529]] normalize = transforms.Normalize(mean=mean_pix, std=std_pix) if (self.phase=='test' or self.phase=='val') or (do_not_use_random_transf==True): self.transform = transforms.Compose([ lambda x: np.asarray(x), transforms.ToTensor(), normalize ]) else: self.transform = transforms.Compose([ transforms.RandomCrop(84, padding=8), transforms.RandomHorizontalFlip(), lambda x: np.asarray(x), transforms.ToTensor(), normalize ]) def __getitem__(self, index): img, label = self.data[index], self.labels[index] # doing this so that it is consistent with all other datasets # to return a PIL Image img = Image.fromarray(img) if self.transform is not None: img = self.transform(img) return img, label def __len__(self): return len(self.data) class FewShotDataloader(): def __init__(self, dataset, nKnovel=5, # number of novel categories. nKbase=-1, # number of base categories. nExemplars=1, # number of training examples per novel category. nTestNovel=15*5, # number of test examples for all the novel categories. nTestBase=15*5, # number of test examples for all the base categories. batch_size=1, # number of training episodes per batch. num_workers=4, epoch_size=2000, # number of batches per epoch. ): self.dataset = dataset self.phase = self.dataset.phase max_possible_nKnovel = (self.dataset.num_cats_base if self.phase=='train' else self.dataset.num_cats_novel) assert(nKnovel >= 0 and nKnovel < max_possible_nKnovel) self.nKnovel = nKnovel max_possible_nKbase = self.dataset.num_cats_base nKbase = nKbase if nKbase >= 0 else max_possible_nKbase if self.phase=='train' and nKbase > 0: nKbase -= self.nKnovel max_possible_nKbase -= self.nKnovel assert(nKbase >= 0 and nKbase <= max_possible_nKbase) self.nKbase = nKbase self.nExemplars = nExemplars self.nTestNovel = nTestNovel self.nTestBase = nTestBase self.batch_size = batch_size self.epoch_size = epoch_size self.num_workers = num_workers self.is_eval_mode = (self.phase=='test') or (self.phase=='val') def sampleImageIdsFrom(self, cat_id, sample_size=1): """ Samples `sample_size` number of unique image ids picked from the category `cat_id` (i.e., self.dataset.label2ind[cat_id]). Args: cat_id: a scalar with the id of the category from which images will be sampled. sample_size: number of images that will be sampled. Returns: image_ids: a list of length `sample_size` with unique image ids. """ assert(cat_id in self.dataset.label2ind) assert(len(self.dataset.label2ind[cat_id]) >= sample_size) # Note: random.sample samples elements without replacement. return random.sample(self.dataset.label2ind[cat_id], sample_size) def sampleCategories(self, cat_set, sample_size=1): """ Samples `sample_size` number of unique categories picked from the `cat_set` set of categories. `cat_set` can be either 'base' or 'novel'. Args: cat_set: string that specifies the set of categories from which categories will be sampled. sample_size: number of categories that will be sampled. Returns: cat_ids: a list of length `sample_size` with unique category ids. """ if cat_set=='base': labelIds = self.dataset.labelIds_base elif cat_set=='novel': labelIds = self.dataset.labelIds_novel else: raise ValueError('Not recognized category set {}'.format(cat_set)) assert(len(labelIds) >= sample_size) # return sample_size unique categories chosen from labelIds set of # categories (that can be either self.labelIds_base or self.labelIds_novel) # Note: random.sample samples elements without replacement. return random.sample(labelIds, sample_size) def sample_base_and_novel_categories(self, nKbase, nKnovel): """ Samples `nKbase` number of base categories and `nKnovel` number of novel categories. Args: nKbase: number of base categories nKnovel: number of novel categories Returns: Kbase: a list of length 'nKbase' with the ids of the sampled base categories. Knovel: a list of lenght 'nKnovel' with the ids of the sampled novel categories. """ if self.is_eval_mode: assert(nKnovel <= self.dataset.num_cats_novel) # sample from the set of base categories 'nKbase' number of base # categories. Kbase = sorted(self.sampleCategories('base', nKbase)) # sample from the set of novel categories 'nKnovel' number of novel # categories. Knovel = sorted(self.sampleCategories('novel', nKnovel)) else: # sample from the set of base categories 'nKnovel' + 'nKbase' number # of categories. cats_ids = self.sampleCategories('base', nKnovel+nKbase) assert(len(cats_ids) == (nKnovel+nKbase)) # Randomly pick 'nKnovel' number of fake novel categories and keep # the rest as base categories. random.shuffle(cats_ids) Knovel = sorted(cats_ids[:nKnovel]) Kbase = sorted(cats_ids[nKnovel:]) return Kbase, Knovel def sample_test_examples_for_base_categories(self, Kbase, nTestBase): """ Sample `nTestBase` number of images from the `Kbase` categories. Args: Kbase: a list of length `nKbase` with the ids of the categories from where the images will be sampled. nTestBase: the total number of images that will be sampled. Returns: Tbase: a list of length `nTestBase` with 2-element tuples. The 1st element of each tuple is the image id that was sampled and the 2nd elemend is its category label (which is in the range [0, len(Kbase)-1]). """ Tbase = [] if len(Kbase) > 0: # Sample for each base category a number images such that the total # number sampled images of all categories to be equal to `nTestBase`. KbaseIndices = np.random.choice( np.arange(len(Kbase)), size=nTestBase, replace=True) KbaseIndices, NumImagesPerCategory = np.unique( KbaseIndices, return_counts=True) for Kbase_idx, NumImages in zip(KbaseIndices, NumImagesPerCategory): imd_ids = self.sampleImageIdsFrom( Kbase[Kbase_idx], sample_size=NumImages) Tbase += [(img_id, Kbase_idx) for img_id in imd_ids] assert(len(Tbase) == nTestBase) return Tbase def sample_train_and_test_examples_for_novel_categories( self, Knovel, nTestNovel, nExemplars, nKbase): """Samples train and test examples of the novel categories. Args: Knovel: a list with the ids of the novel categories. nTestNovel: the total number of test images that will be sampled from all the novel categories. nExemplars: the number of training examples per novel category that will be sampled. nKbase: the number of base categories. It is used as offset of the category index of each sampled image. Returns: Tnovel: a list of length `nTestNovel` with 2-element tuples. The 1st element of each tuple is the image id that was sampled and the 2nd element is its category label (which is in the range [nKbase, nKbase + len(Knovel) - 1]). Exemplars: a list of length len(Knovel) * nExemplars of 2-element tuples. The 1st element of each tuple is the image id that was sampled and the 2nd element is its category label (which is in the ragne [nKbase, nKbase + len(Knovel) - 1]). """ if len(Knovel) == 0: return [], [] nKnovel = len(Knovel) Tnovel = [] Exemplars = [] assert((nTestNovel % nKnovel) == 0) nEvalExamplesPerClass = nTestNovel / nKnovel for Knovel_idx in range(len(Knovel)): imd_ids = self.sampleImageIdsFrom( Knovel[Knovel_idx], sample_size=(nEvalExamplesPerClass + nExemplars)) imds_tnovel = imd_ids[:nEvalExamplesPerClass] imds_ememplars = imd_ids[nEvalExamplesPerClass:] Tnovel += [(img_id, nKbase+Knovel_idx) for img_id in imds_tnovel] Exemplars += [(img_id, nKbase+Knovel_idx) for img_id in imds_ememplars] assert(len(Tnovel) == nTestNovel) assert(len(Exemplars) == len(Knovel) * nExemplars) random.shuffle(Exemplars) return Tnovel, Exemplars def sample_episode(self): """Samples a training episode.""" nKnovel = self.nKnovel nKbase = self.nKbase nTestNovel = self.nTestNovel nTestBase = self.nTestBase nExemplars = self.nExemplars Kbase, Knovel = self.sample_base_and_novel_categories(nKbase, nKnovel) Tbase = self.sample_test_examples_for_base_categories(Kbase, nTestBase) Tnovel, Exemplars = self.sample_train_and_test_examples_for_novel_categories( Knovel, nTestNovel, nExemplars, nKbase) # concatenate the base and novel category examples. Test = Tbase + Tnovel random.shuffle(Test) Kall = Kbase + Knovel return Exemplars, Test, Kall, nKbase def createExamplesTensorData(self, examples): """ Creates the examples image and label tensor data. Args: examples: a list of 2-element tuples, each representing a train or test example. The 1st element of each tuple is the image id of the example and 2nd element is the category label of the example, which is in the range [0, nK - 1], where nK is the total number of categories (both novel and base). Returns: images: a tensor of shape [nExamples, Height, Width, 3] with the example images, where nExamples is the number of examples (i.e., nExamples = len(examples)). labels: a tensor of shape [nExamples] with the category label of each example. """ images = torch.stack( [self.dataset[img_idx][0] for img_idx, _ in examples], dim=0) labels = torch.LongTensor([label for _, label in examples]) return images, labels def get_iterator(self, epoch=0): rand_seed = epoch random.seed(rand_seed) np.random.seed(rand_seed) def load_function(iter_idx): Exemplars, Test, Kall, nKbase = self.sample_episode() Xt, Yt = self.createExamplesTensorData(Test) Kall = torch.LongTensor(Kall) if len(Exemplars) > 0: Xe, Ye = self.createExamplesTensorData(Exemplars) return Xe, Ye, Xt, Yt, Kall, nKbase else: return Xt, Yt, Kall, nKbase tnt_dataset = tnt.dataset.ListDataset( elem_list=range(self.epoch_size), load=load_function) data_loader = tnt_dataset.parallel( batch_size=self.batch_size, num_workers=(0 if self.is_eval_mode else self.num_workers), shuffle=(False if self.is_eval_mode else True)) return data_loader def __call__(self, epoch=0): return self.get_iterator(epoch) def __len__(self): return (self.epoch_size / self.batch_size) class ImageNetLowShot(data.Dataset): def __init__(self, phase='train', split='train', do_not_use_random_transf=False): self.phase = phase self.split = split assert(phase=='train' or phase=='test' or phase=='val') assert(split=='train' or split=='val') self.name = 'ImageNetLowShot_Phase_' + phase + '_Split_' + split print('Loading ImageNet dataset (for few-shot benchmark) - phase {0}'. format(phase)) #*********************************************************************** with open(_IMAGENET_LOWSHOT_BENCHMARK_CATEGORY_SPLITS_PATH, 'r') as f: label_idx = json.load(f) base_classes = label_idx['base_classes'] novel_classes_val_phase = label_idx['novel_classes_1'] novel_classes_test_phase = label_idx['novel_classes_2'] #*********************************************************************** transforms_list = [] if (phase!='train') or (do_not_use_random_transf==True): transforms_list.append(transforms.Scale(256)) transforms_list.append(transforms.CenterCrop(224)) else: transforms_list.append(transforms.RandomSizedCrop(224)) jitter_params = {'Brightness': 0.4, 'Contrast': 0.4, 'Color': 0.4} transforms_list.append(ImageJitter(jitter_params)) transforms_list.append(transforms.RandomHorizontalFlip()) transforms_list.append(lambda x: np.asarray(x)) transforms_list.append(transforms.ToTensor()) mean_pix = [0.485, 0.456, 0.406] std_pix = [0.229, 0.224, 0.225] transforms_list.append(transforms.Normalize(mean=mean_pix, std=std_pix)) self.transform = transforms.Compose(transforms_list) traindir = os.path.join(_IMAGENET_DATASET_DIR, 'train') valdir = os.path.join(_IMAGENET_DATASET_DIR, 'val') self.data = datasets.ImageFolder( traindir if split=='train' else valdir, self.transform) self.labels = [item[1] for item in self.data.imgs] self.label2ind = buildLabelIndex(self.labels) self.labelIds = sorted(self.label2ind.keys()) self.num_cats = len(self.labelIds) assert(self.num_cats==1000) self.labelIds_base = base_classes self.num_cats_base = len(self.labelIds_base) if self.phase=='val' or self.phase=='test': self.labelIds_novel = ( novel_classes_val_phase if (self.phase=='val') else novel_classes_test_phase) self.num_cats_novel = len(self.labelIds_novel) intersection = set(self.labelIds_base) & set(self.labelIds_novel) assert(len(intersection) == 0) def __getitem__(self, index): img, label = self.data[index] return img, label def __len__(self): return len(self.data) class ImageNet(data.Dataset): def __init__(self, split='train'): self.split = split assert(split=='train' or split=='val') self.name = 'ImageNet_Split_' + split print('Loading ImageNet dataset - split {0}'.format(split)) transforms_list = [] transforms_list.append(transforms.Scale(256)) transforms_list.append(transforms.CenterCrop(224)) transforms_list.append(lambda x: np.asarray(x)) transforms_list.append(transforms.ToTensor()) mean_pix = [0.485, 0.456, 0.406] std_pix = [0.229, 0.224, 0.225] transforms_list.append(transforms.Normalize(mean=mean_pix, std=std_pix)) self.transform = transforms.Compose(transforms_list) traindir = os.path.join(_IMAGENET_DATASET_DIR, 'train') valdir = os.path.join(_IMAGENET_DATASET_DIR, 'val') self.data = datasets.ImageFolder( traindir if split=='train' else valdir, self.transform) self.labels = [item[1] for item in self.data.imgs] def __getitem__(self, index): img, label = self.data[index] return img, label def __len__(self): return len(self.data) class SimpleDataloader(): def __init__(self, dataset, batch_size, num_workers=4): self.dataset = dataset self.batch_size = batch_size self.num_workers = num_workers self.epoch_size = len(dataset) def get_iterator(self): def load_fun_(idx): img, label = self.dataset[idx] return img, label tnt_dataset = tnt.dataset.ListDataset( elem_list=range(self.epoch_size), load=load_fun_) data_loader = tnt_dataset.parallel( batch_size=self.batch_size, num_workers=self.num_workers, shuffle=False, drop_last=False) return data_loader def __call__(self): return self.get_iterator() def __len__(self): return (self.epoch_size / self.batch_size) class ImageNetLowShotFeaturesLegacy(): def __init__( self, data_dir, phase='train', add_novel_split='val'): self.phase = phase assert(phase=='train' or phase=='test' or phase=='val') self.name = 'ImageNetLowShotFeatures_Phase_' + phase split = 'train' if (phase=='train') else 'val' dataset_file = os.path.join(data_dir, 'feature_dataset_'+split+'.json') self.data_file = h5py.File(dataset_file, 'r') self.count = self.data_file['count'][0] self.features = self.data_file['all_features'][...] self.labels = self.data_file['all_labels'][:self.count].tolist() #*********************************************************************** with open(_IMAGENET_LOWSHOT_BENCHMARK_CATEGORY_SPLITS_PATH, 'r') as f: label_idx = json.load(f) base_classes = label_idx['base_classes'] base_classes_val_phase = label_idx['base_classes_1'] base_classes_test_phase = label_idx['base_classes_2'] novel_classes_val_phase = label_idx['novel_classes_1'] novel_classes_test_phase = label_idx['novel_classes_2'] #*********************************************************************** self.label2ind = buildLabelIndex(self.labels) self.labelIds = sorted(self.label2ind.keys()) self.num_cats = len(self.labelIds) assert(self.num_cats==1000) self.labelIds_base = base_classes self.num_cats_base = len(self.labelIds_base) novel_split = add_novel_split if (self.phase=='train') else self.phase if novel_split=='val' or novel_split=='test': self.labelIds_novel = ( novel_classes_val_phase if (novel_split=='val') else novel_classes_test_phase) self.num_cats_novel = len(self.labelIds_novel) intersection = set(self.labelIds_base) & set(self.labelIds_novel) assert(len(intersection) == 0) self.base_classes_subset = ( base_classes_val_phase if (novel_split=='val') else base_classes_test_phase) else: self.base_classes_subset = base_classes def __getitem__(self, index): features_this = torch.Tensor(self.features[index]).view(-1,1,1) label_this = self.labels[index] return features_this, label_this def __len__(self): return int(self.count) class ImageNetLowShotFeatures(): def __init__( self, data_dir, # path to the directory with the saved ImageNet features. image_split='train', # the image split of the ImageNet that will be loaded. phase='train', # whether the dataset will be used for training, validating, or testing a model. ): assert(image_split=='train' or image_split=='val') assert(phase=='train' or phase=='val' or phase=='test') self.phase = phase self.image_split = image_split self.name = ('ImageNetLowShotFeatures_ImageSplit_' + self.image_split +'_Phase_' + self.phase) dataset_file = os.path.join( data_dir, 'feature_dataset_' + self.image_split + '.json') self.data_file = h5py.File(dataset_file, 'r') self.count = self.data_file['count'][0] self.features = self.data_file['all_features'][...] self.labels = self.data_file['all_labels'][:self.count].tolist() #*********************************************************************** with open(_IMAGENET_LOWSHOT_BENCHMARK_CATEGORY_SPLITS_PATH, 'r') as f: label_idx = json.load(f) base_classes = label_idx['base_classes'] base_classes_val_split = label_idx['base_classes_1'] base_classes_test_split = label_idx['base_classes_2'] novel_classes_val_split = label_idx['novel_classes_1'] novel_classes_test_split = label_idx['novel_classes_2'] #*********************************************************************** self.label2ind = buildLabelIndex(self.labels) self.labelIds = sorted(self.label2ind.keys()) self.num_cats = len(self.labelIds) assert(self.num_cats==1000) self.labelIds_base = base_classes self.num_cats_base = len(self.labelIds_base) if self.phase=='val' or self.phase=='test': self.labelIds_novel = ( novel_classes_val_split if (self.phase=='val') else novel_classes_test_split) self.num_cats_novel = len(self.labelIds_novel) intersection = set(self.labelIds_base) & set(self.labelIds_novel) assert(len(intersection) == 0) self.base_classes_eval_split = ( base_classes_val_split if (self.phase=='val') else base_classes_test_split) self.base_classes_subset = self.base_classes_eval_split def __getitem__(self, index): features_this = torch.Tensor(self.features[index]).view(-1,1,1) label_this = self.labels[index] return features_this, label_this def __len__(self): return int(self.count) class LowShotDataloader(): def __init__( self, dataset_train_novel, dataset_evaluation, nExemplars=1, batch_size=1, num_workers=4): self.nExemplars = nExemplars self.batch_size = batch_size self.num_workers = num_workers self.dataset_train_novel = dataset_train_novel self.dataset_evaluation = dataset_evaluation assert(self.dataset_evaluation.labelIds_novel == self.dataset_train_novel.labelIds_novel) assert(self.dataset_evaluation.labelIds_base == self.dataset_train_novel.labelIds_base) assert(self.dataset_evaluation.base_classes_eval_split == self.dataset_train_novel.base_classes_eval_split) self.nKnovel = self.dataset_evaluation.num_cats_novel self.nKbase = self.dataset_evaluation.num_cats_base # Category ids of the base categories. self.Kbase = sorted(self.dataset_evaluation.labelIds_base) assert(self.nKbase == len(self.Kbase)) # Category ids of the novel categories. self.Knovel = sorted(self.dataset_evaluation.labelIds_novel) assert(self.nKnovel == len(self.Knovel)) self.Kall = self.Kbase + self.Knovel self.CategoryId2LabelIndex = { category_id: label_index for label_index, category_id in enumerate(self.Kall) } self.Kbase_eval_split = self.dataset_train_novel.base_classes_eval_split Kbase_set = set(self.Kall[:self.nKbase]) Kbase_eval_split_set = set(self.Kbase_eval_split) assert(len(set.intersection(Kbase_set, Kbase_eval_split_set)) == len(Kbase_eval_split_set)) self.base_eval_split_labels = sorted( [self.CategoryId2LabelIndex[category_id] for category_id in self.Kbase_eval_split] ) # Collect the image indices of the evaluation set for both the base and # the novel categories. data_indices = [] for category_id in self.Kbase_eval_split: data_indices += self.dataset_evaluation.label2ind[category_id] for category_id in self.Knovel: data_indices += self.dataset_evaluation.label2ind[category_id] self.eval_data_indices = sorted(data_indices) self.epoch_size = len(self.eval_data_indices) def base_category_label_indices(self): return self.base_eval_split_labels def novel_category_label_indices(self): return range(self.nKbase, len(self.Kall)) def sampleImageIdsFrom(self, cat_id, sample_size=1): """ Samples `sample_size` number of unique image ids picked from the category `cat_id` (i.e., self.dataset_train_novel.label2ind[cat_id]). Args: cat_id: a scalar with the id of the category from which images will be sampled. sample_size: number of images that will be sampled. Returns: image_ids: a list of length `sample_size` with unique image ids. """ assert(cat_id in self.dataset_train_novel.label2ind) assert(len(self.dataset_train_novel.label2ind[cat_id]) >= sample_size) # Note: random.sample samples elements without replacement. return random.sample(self.dataset_train_novel.label2ind[cat_id], sample_size) def sample_training_examples_for_novel_categories( self, Knovel, nExemplars, nKbase): """Samples (a few) training examples for the novel categories. Args: Knovel: a list with the ids of the novel categories. nExemplars: the number of training examples per novel category. nKbase: the number of base categories. Returns: Exemplars: a list of length len(Knovel) * nExemplars of 2-element tuples. The 1st element of each tuple is the image id that was sampled and the 2nd element is its category label (which is in the ragne [nKbase, nKbase + len(Knovel) - 1]). """ Exemplars = [] for knovel_idx, knovel_label in enumerate(Knovel): imds = self.sampleImageIdsFrom(knovel_label, sample_size=nExemplars) Exemplars += [(img_id, nKbase + knovel_idx) for img_id in imds] random.shuffle(Exemplars) return Exemplars def create_examples_tensor_data(self, examples): """ Creates the examples image and label tensor data. Args: examples: a list of 2-element tuples, each representing a train or test example. The 1st element of each tuple is the image id of the example and 2nd element is the category label of the example, which is in the range [0, nK - 1], where nK is the total number of categories (both novel and base). Returns: images: a tensor of shape [nExamples, Height, Width, 3] with the example images, where nExamples is the number of examples (i.e., nExamples = len(examples)). labels: a tensor of shape [nExamples] with the category label of each example. """ images = torch.stack( [self.dataset_train_novel[img_idx][0] for img_idx, _ in examples], dim=0) labels = torch.LongTensor([label for _, label in examples]) return images, labels def sample_training_data_for_novel_categories(self, exp_id=0): nKnovel = self.nKnovel nKbase = self.nKbase random.seed(exp_id) # fix the seed for this experiment. # Sample `nExemplars` number of training examples per novel category. train_examples = self.sample_training_examples_for_novel_categories( self.Knovel, self.nExemplars, nKbase) Kall = torch.LongTensor(self.Kall) images_train, labels_train = self.create_examples_tensor_data( train_examples) return images_train, labels_train, Kall, nKbase, nKnovel def get_iterator(self, epoch=0): def load_fun_(idx): img_idx = self.eval_data_indices[idx] img, category_id = self.dataset_evaluation[img_idx] label = (self.CategoryId2LabelIndex[category_id] if (category_id in self.CategoryId2LabelIndex) else -1) return img, label tnt_dataset = tnt.dataset.ListDataset( elem_list=range(self.epoch_size), load=load_fun_) data_loader = tnt_dataset.parallel( batch_size=self.batch_size, num_workers=self.num_workers, shuffle=False, drop_last=False) return data_loader def __call__(self, epoch=0): return self.get_iterator(epoch) def __len__(self): return int(math.ceil(float(self.epoch_size)/self.batch_size)) class LowShotDataloaderLegacy(): def __init__( self, dataset_train_novel, dataset_evaluation, nExemplars=1, batch_size=1, num_workers=4): self.dataset_train_novel = dataset_train_novel self.dataset_evaluation = dataset_evaluation assert(self.dataset_evaluation.labelIds_novel == self.dataset_train_novel.labelIds_novel) # Collect the image indices of the evaluation set for both the base and # the novel categories. data_inds = [] for kid in self.dataset_evaluation.labelIds_base: data_inds += self.dataset_evaluation.label2ind[kid] for kid in self.dataset_evaluation.labelIds_novel: data_inds += self.dataset_evaluation.label2ind[kid] self.eval_data_indices = sorted(data_inds) self.nKnovel = self.dataset_evaluation.num_cats_novel self.nKbase = self.dataset_evaluation.num_cats_base self.nExemplars = nExemplars self.batch_size = batch_size self.epoch_size = len(self.eval_data_indices) self.num_workers = num_workers def sampleImageIdsFrom(self, cat_id, sample_size=1): """ Samples `sample_size` number of unique image ids picked from the category `cat_id` (i.e., self.dataset_train_novel.label2ind[cat_id]). Args: cat_id: a scalar with the id of the category from which images will be sampled. sample_size: number of images that will be sampled. Returns: image_ids: a list of length `sample_size` with unique image ids. """ assert(cat_id in self.dataset_train_novel.label2ind) assert(len(self.dataset_train_novel.label2ind[cat_id]) >= sample_size) # Note: random.sample samples elements without replacement. return random.sample(self.dataset_train_novel.label2ind[cat_id], sample_size) def sampleCategories(self, cat_set, sample_size=1): """ Samples `sample_size` number of unique categories picked from the `cat_set` set of categories. `cat_set` can be either 'base' or 'novel'. Args: cat_set: string that specifies the set of categories from which categories will be sampled. sample_size: number of categories that will be sampled. Returns: cat_ids: a list of length `sample_size` with unique category ids. """ if cat_set=='base': labelIds = self.dataset_evaluation.labelIds_base elif cat_set=='novel': labelIds = self.dataset_evaluation.labelIds_novel else: raise ValueError('Not recognized category set {}'.format(cat_set)) assert(len(labelIds) >= sample_size) # return sample_size unique categories chosen from labelIds set of # categories (that can be either self.labelIds_base or self.labelIds_novel) # Note: random.sample samples elements without replacement. return random.sample(labelIds, sample_size) def sample_novel_data(self): """Samples a few training examples for each novel category.""" nKnovel = self.nKnovel nKbase = self.nKbase nExemplars = self.nExemplars # Kbase = sorted(self.dataset_evaluation.labelIds_base) # Knovel = sorted(self.dataset_evaluation.labelIds_novel) Kbase = sorted(self.sampleCategories('base', nKbase)) Knovel = sorted(self.sampleCategories('novel', nKnovel)) Exemplars = [] for knovel_idx, knovel_label in enumerate(Knovel): imds = self.sampleImageIdsFrom(knovel_label, sample_size=nExemplars) Exemplars += [(img_id, nKbase + knovel_idx) for img_id in imds] random.shuffle(Exemplars) Kids = Kbase + Knovel return Exemplars, Kids, nKbase, nKnovel def create_examples_tensor_data(self, examples): """ Creates the examples image and label tensor data. Args: examples: a list of 2-element tuples, each representing a train or test example. The 1st element of each tuple is the image id of the example and 2nd element is the category label of the example, which is in the range [0, nK - 1], where nK is the total number of categories (both novel and base). Returns: images: a tensor of shape [nExamples, Height, Width, 3] with the example images, where nExamples is the number of examples (i.e., nExamples = len(examples)). labels: a tensor of shape [nExamples] with the category label of each example. """ images = torch.stack( [self.dataset_train_novel[img_idx][0] for img_idx, _ in examples], dim=0) labels = torch.LongTensor([label for _, label in examples]) return images, labels def getNovelCategoriesTrainingData(self, exp_id=0): random.seed(exp_id) # fix the seed for this experiment. # Sample training examples for each novel category. Exemplars, Kids, nKbase, nKnovel = self.sample_novel_data() self.Kid2Label = {kid: label_idx for label_idx, kid in enumerate(Kids)} base_classes_subset = self.dataset_train_novel.base_classes_subset assert(len(set.intersection(set(Kids[:nKbase]),set(base_classes_subset))) == len(base_classes_subset)) self.Kids_base_subset = sorted([self.Kid2Label[kid] for kid in base_classes_subset]) Kids = torch.LongTensor(Kids) Xe, Ye = self.create_examples_tensor_data(Exemplars) return Xe, Ye, Kids, nKbase, nKnovel def sample_training_data_of_novel_categories(self, exp_id=0): nKnovel = self.nKnovel nKbase = self.nKbase nExemplars = self.nExemplars random.seed(exp_id) # fix the seed for this experiment. breakpoint() # Ids of the base categories. Kbase = sorted(self.dataset_evaluation.labelIds_base) # Ids of the novel categories. Knovel = sorted(self.dataset_evaluation.labelIds_novel) assert(len(Kbase) == nKnovel and len(Knovel) == nKbase) Kall = Kbase + Knovel # Sample `nExemplars` number of training examples for each novel # category. train_examples = self.sample_training_examples_for_novel_categories( Knovel, nExemplars) breakpoint() self.Kid2Label = {kid: label_idx for label_idx, kid in enumerate(Kall)} breakpoint() base_classes_subset = self.dataset_train_novel.base_classes_subset assert(len(set.intersection(set(Kall[:nKbase]),set(base_classes_subset))) == len(base_classes_subset)) self.Kids_base_subset = sorted([self.Kid2Label[kid] for kid in base_classes_subset]) Kall = torch.LongTensor(Kall) images_train, labels_train = self.create_examples_tensor_data(train_examples) return images_train, labels_train, Kall, nKbase, nKnovel def get_iterator(self, epoch=0): def load_fun_(idx): img_idx = self.eval_data_indices[idx] img, kid = self.dataset_evaluation[img_idx] label = self.Kid2Label[kid] if (kid in self.Kid2Label) else -1 return img, label tnt_dataset = tnt.dataset.ListDataset( elem_list=range(self.epoch_size), load=load_fun_) data_loader = tnt_dataset.parallel( batch_size=self.batch_size, num_workers=self.num_workers, shuffle=False, drop_last=False) return data_loader def __call__(self, epoch=0): return self.get_iterator(epoch) def __len__(self): return int(math.ceil(float(self.epoch_size)/self.batch_size))