File size: 9,349 Bytes
5a444be
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
# Copyright (c) Facebook, Inc. and its affiliates.
# Modified by Jialian Wu from https://github.com/facebookresearch/Detic/blob/main/detic/data/custom_dataset_dataloader.py
import operator
import torch
import torch.utils.data
from detectron2.utils.comm import get_world_size

from detectron2.config import configurable
from torch.utils.data.sampler import BatchSampler, Sampler
from detectron2.data.common import DatasetFromList, MapDataset
from detectron2.data.dataset_mapper import DatasetMapper
from detectron2.data.build import get_detection_dataset_dicts, build_batch_data_loader
from detectron2.data.samplers import TrainingSampler
from detectron2.data.build import worker_init_reset_seed, print_instances_class_histogram
from detectron2.data.build import filter_images_with_only_crowd_annotations
from detectron2.data.build import filter_images_with_few_keypoints
from detectron2.data.build import check_metadata_consistency
from detectron2.data.catalog import MetadataCatalog, DatasetCatalog
from detectron2.utils import comm
import itertools
from typing import Optional


def _custom_train_loader_from_config(cfg, mapper=None, *, dataset=None, sampler=None):
    sampler_name = cfg.DATALOADER.SAMPLER_TRAIN
    if 'MultiDataset' in sampler_name:
        dataset_dicts = get_detection_dataset_dicts_with_source(
            cfg.DATASETS.TRAIN,
            filter_empty=cfg.DATALOADER.FILTER_EMPTY_ANNOTATIONS,
            min_keypoints=cfg.MODEL.ROI_KEYPOINT_HEAD.MIN_KEYPOINTS_PER_IMAGE
            if cfg.MODEL.KEYPOINT_ON else 0,
            proposal_files=cfg.DATASETS.PROPOSAL_FILES_TRAIN if cfg.MODEL.LOAD_PROPOSALS else None,
        )
    else:
        dataset_dicts = get_detection_dataset_dicts(
            cfg.DATASETS.TRAIN,
            filter_empty=cfg.DATALOADER.FILTER_EMPTY_ANNOTATIONS,
            min_keypoints=cfg.MODEL.ROI_KEYPOINT_HEAD.MIN_KEYPOINTS_PER_IMAGE
            if cfg.MODEL.KEYPOINT_ON else 0,
            proposal_files=cfg.DATASETS.PROPOSAL_FILES_TRAIN if cfg.MODEL.LOAD_PROPOSALS else None,
        )

    if mapper is None:
        mapper = DatasetMapper(cfg, True)

    if sampler is not None:
        pass
    elif sampler_name == "TrainingSampler":
        sampler = TrainingSampler(len(dataset))
    elif sampler_name == "MultiDatasetSampler":
        sampler = MultiDatasetSampler(
            dataset_dicts,
            dataset_ratio=cfg.DATALOADER.DATASET_RATIO,
        )
    else:
        raise ValueError("Unknown training sampler: {}".format(sampler_name))

    return {
        "dataset": dataset_dicts,
        "sampler": sampler,
        "mapper": mapper,
        "total_batch_size": cfg.SOLVER.IMS_PER_BATCH,
        "num_workers": cfg.DATALOADER.NUM_WORKERS,
        'dataset_bs': cfg.DATALOADER.DATASET_BS,
        'num_datasets': len(cfg.DATASETS.TRAIN)
    }


@configurable(from_config=_custom_train_loader_from_config)
def build_custom_train_loader(
        dataset, *, mapper, sampler, 
        total_batch_size=16,
        num_workers=0,
        num_datasets=1,
        dataset_bs=1
):

    if isinstance(dataset, list):
        dataset = DatasetFromList(dataset, copy=False)
    if mapper is not None:
        dataset = MapDataset(dataset, mapper)
    if sampler is None:
        sampler = TrainingSampler(len(dataset))
    assert isinstance(sampler, torch.utils.data.sampler.Sampler)

    return build_dataset_batch_data_loader(
        dataset_bs,
        dataset,
        sampler,
        total_batch_size,
        num_datasets=num_datasets,
        num_workers=num_workers,
    )


def build_dataset_batch_data_loader(
    dataset_bs, dataset, sampler, total_batch_size, num_datasets, num_workers=0
):

    world_size = get_world_size()
    assert (
        total_batch_size > 0 and total_batch_size % world_size == 0
    ), "Total batch size ({}) must be divisible by the number of gpus ({}).".format(
        total_batch_size, world_size
    )

    data_loader = torch.utils.data.DataLoader(
        dataset,
        sampler=sampler,
        num_workers=num_workers,
        batch_sampler=None,
        collate_fn=operator.itemgetter(0),  # don't batch, but yield individual elements
        worker_init_fn=worker_init_reset_seed,
    )

    if num_datasets > 1:
        return MultiDatasets(data_loader, dataset_bs, num_datasets)
    else:
        return SingleDataset(data_loader, dataset_bs)


def get_detection_dataset_dicts_with_source(
    dataset_names, filter_empty=True, min_keypoints=0, proposal_files=None
):
    assert len(dataset_names)
    dataset_dicts = [DatasetCatalog.get(dataset_name) for dataset_name in dataset_names]
    for dataset_name, dicts in zip(dataset_names, dataset_dicts):
        assert len(dicts), "Dataset '{}' is empty!".format(dataset_name)
    
    for source_id, (dataset_name, dicts) in \
        enumerate(zip(dataset_names, dataset_dicts)):
        assert len(dicts), "Dataset '{}' is empty!".format(dataset_name)
        for d in dicts:
            d['dataset_source'] = source_id

        if "annotations" in dicts[0]:
            try:
                class_names = MetadataCatalog.get(dataset_name).thing_classes
                check_metadata_consistency("thing_classes", dataset_name)
                print_instances_class_histogram(dicts, class_names)
            except AttributeError:  # class names are not available for this dataset
                pass

    assert proposal_files is None

    dataset_dicts = list(itertools.chain.from_iterable(dataset_dicts))

    has_instances = "annotations" in dataset_dicts[0]
    if filter_empty and has_instances:
        dataset_dicts = filter_images_with_only_crowd_annotations(dataset_dicts)
    if min_keypoints > 0 and has_instances:
        dataset_dicts = filter_images_with_few_keypoints(dataset_dicts, min_keypoints)

    return dataset_dicts


class MultiDatasetSampler(Sampler):
    def __init__(
        self, 
        dataset_dicts, 
        dataset_ratio,
        seed: Optional[int] = None,
    ):
        sizes = [0 for _ in range(len(dataset_ratio))]
        for d in dataset_dicts:
            sizes[d['dataset_source']] += 1
        print('dataset sizes', sizes)
        self.sizes = sizes
        assert len(dataset_ratio) == len(sizes), \
            'length of dataset ratio {} should be equal to number if dataset {}'.format(
                len(dataset_ratio), len(sizes)
            )
        if seed is None:
            seed = comm.shared_random_seed()
        self._seed = int(seed)
        self._rank = comm.get_rank()
        self._world_size = comm.get_world_size()
        
        self.dataset_ids = torch.tensor(
            [d['dataset_source'] for d in dataset_dicts], dtype=torch.long)
        self.dataset_ratio = dataset_ratio

        dataset_weight = [torch.ones(s) * max(sizes) / s * r / sum(dataset_ratio) \
            for i, (r, s) in enumerate(zip(dataset_ratio, sizes))]
        dataset_weight = torch.cat(dataset_weight)

        self.weights = dataset_weight
        self.sample_epoch_size = len(self.weights)

    def __iter__(self):
        start = self._rank
        yield from itertools.islice(
            self._infinite_indices(), start, None, self._world_size)

    def _infinite_indices(self):
        g = torch.Generator()
        g.manual_seed(self._seed)
        while True:
            if len(self.dataset_ratio) > 1:
                # multiple datasets
                ids = torch.multinomial(
                    self.weights, self.sample_epoch_size, generator=g,
                    replacement=True)
                nums = [(self.dataset_ids[ids] == i).sum().int().item() \
                    for i in range(len(self.sizes))]
                yield from ids
            else:
                # single dataset
                yield from torch.randperm(self.sizes[0], generator=g).tolist()


class SingleDataset(torch.utils.data.IterableDataset):
    def __init__(self, dataset, batch_sizes):
        self.dataset = dataset
        self.batch_sizes = batch_sizes
        self._buckets = [[] for _ in range(2)]

    def __iter__(self):
        for d in self.dataset:
            w, h = d["width"], d["height"]
            aspect_ratio_bucket_id = 0 if w > h else 1
            bucket_id = aspect_ratio_bucket_id
            bucket = self._buckets[bucket_id]
            bucket.append(d)
            if len(bucket) == self.batch_sizes:
                yield bucket[:]
                del bucket[:]


class MultiDatasets(torch.utils.data.IterableDataset):
    def __init__(self, dataset, batch_sizes, num_datasets):
        self.dataset = dataset
        self.batch_sizes = batch_sizes
        self._buckets = [[] for _ in range(2 * num_datasets)]
        self.iter_idx = 0
        self.num_datasets = num_datasets

    def __iter__(self):
        for d in self.dataset:
            w, h = d["width"], d["height"]
            aspect_ratio_bucket_id = 0 if w > h else 1
            bucket_id = d['dataset_source'] * 2 + aspect_ratio_bucket_id
            bucket = self._buckets[bucket_id]
            if len(bucket) < self.batch_sizes:
                bucket.append(d)
            selected_dataset = self.iter_idx % self.num_datasets
            if len(bucket) == self.batch_sizes and selected_dataset == d['dataset_source']:
                self.iter_idx += 1
                yield bucket[:]
                del bucket[:]