diff --git a/torchreid/data_manager.py b/torchreid/data_manager.py
index dc2e127..aab9df4 100644
--- a/torchreid/data_manager.py
+++ b/torchreid/data_manager.py
@@ -46,7 +46,9 @@ class BaseDataManager(object):
         self.num_instances = num_instances
 
         transform_train, transform_test = build_transforms(
-            self.height, self.width, random_erase=self.random_erase, color_jitter=self.color_jitter,
+            self.height, self.width,
+            random_erase=self.random_erase,
+            color_jitter=self.color_jitter,
             color_aug=self.color_aug
         )
         self.transform_train = transform_train
@@ -61,22 +63,15 @@ class BaseDataManager(object):
         return self._num_train_cams
 
     def return_dataloaders(self):
-        """
-        Return trainloader and testloader dictionary
-        """
+        """Return trainloader and testloader dictionary"""
         return self.trainloader, self.testloader_dict
 
     def return_testdataset_by_name(self, name):
-        """
-        Return query and gallery, each containing a list of (img_path, pid, camid).
-        """
+        """Return query and gallery, each containing a list of (img_path, pid, camid)"""
         return self.testdataset_dict[name]['query'], self.testdataset_dict[name]['gallery']
 
 
 class ImageDataManager(BaseDataManager):
-    """
-    Image-ReID data manager
-    """
 
     def __init__(self,
                  use_gpu,
@@ -92,15 +87,19 @@ class ImageDataManager(BaseDataManager):
         self.cuhk03_classic_split = cuhk03_classic_split
         self.market1501_500k = market1501_500k
 
-        print('=> Initializing TRAIN (source) datasets')
+        print('=> Initializing train (source) datasets')
         train = []
         self._num_train_pids = 0
         self._num_train_cams = 0
 
         for name in self.source_names:
             dataset = init_imgreid_dataset(
-                root=self.root, name=name, split_id=self.split_id, cuhk03_labeled=self.cuhk03_labeled,
-                cuhk03_classic_split=self.cuhk03_classic_split, market1501_500k=self.market1501_500k
+                root=self.root,
+                name=name,
+                split_id=self.split_id,
+                cuhk03_labeled=self.cuhk03_labeled,
+                cuhk03_classic_split=self.cuhk03_classic_split,
+                market1501_500k=self.market1501_500k
             )
 
             for img_path, pid, camid in dataset.train:
@@ -112,37 +111,52 @@ class ImageDataManager(BaseDataManager):
             self._num_train_cams += dataset.num_train_cams
 
         self.train_sampler = build_train_sampler(
-            train, self.train_sampler,
+            train,
+            self.train_sampler,
             train_batch_size=self.train_batch_size,
             num_instances=self.num_instances,
         )
 
         self.trainloader = DataLoader(
-            ImageDataset(train, transform=self.transform_train), sampler=self.train_sampler,
-            batch_size=self.train_batch_size, shuffle=False, num_workers=self.workers,
-            pin_memory=self.use_gpu, drop_last=True
+            ImageDataset(train, transform=self.transform_train),
+            sampler=self.train_sampler,
+            batch_size=self.train_batch_size,
+            shuffle=False,
+            num_workers=self.workers,
+            pin_memory=self.use_gpu,
+            drop_last=True
         )
 
-        print('=> Initializing TEST (target) datasets')
+        print('=> Initializing test (target) datasets')
         self.testloader_dict = {name: {'query': None, 'gallery': None} for name in target_names}
         self.testdataset_dict = {name: {'query': None, 'gallery': None} for name in target_names}
         
         for name in self.target_names:
             dataset = init_imgreid_dataset(
-                root=self.root, name=name, split_id=self.split_id, cuhk03_labeled=self.cuhk03_labeled,
-                cuhk03_classic_split=self.cuhk03_classic_split, market1501_500k=self.market1501_500k
+                root=self.root,
+                name=name,
+                split_id=self.split_id,
+                cuhk03_labeled=self.cuhk03_labeled,
+                cuhk03_classic_split=self.cuhk03_classic_split,
+                market1501_500k=self.market1501_500k
             )
 
             self.testloader_dict[name]['query'] = DataLoader(
                 ImageDataset(dataset.query, transform=self.transform_test),
-                batch_size=self.test_batch_size, shuffle=False, num_workers=self.workers,
-                pin_memory=self.use_gpu, drop_last=False
+                batch_size=self.test_batch_size,
+                shuffle=False,
+                num_workers=self.workers,
+                pin_memory=self.use_gpu,
+                drop_last=False
             )
 
             self.testloader_dict[name]['gallery'] = DataLoader(
                 ImageDataset(dataset.gallery, transform=self.transform_test),
-                batch_size=self.test_batch_size, shuffle=False, num_workers=self.workers,
-                pin_memory=self.use_gpu, drop_last=False
+                batch_size=self.test_batch_size,
+                shuffle=False,
+                num_workers=self.workers,
+                pin_memory=self.use_gpu,
+                drop_last=False
             )
 
             self.testdataset_dict[name]['query'] = dataset.query
@@ -161,9 +175,6 @@ class ImageDataManager(BaseDataManager):
 
 
 class VideoDataManager(BaseDataManager):
-    """
-    Video-ReID data manager
-    """
 
     def __init__(self,
                  use_gpu,
@@ -179,7 +190,7 @@ class VideoDataManager(BaseDataManager):
         self.sample_method = sample_method
         self.image_training = image_training
 
-        print('=> Initializing TRAIN (source) datasets')
+        print('=> Initializing train (source) datasets')
         train = []
         self._num_train_pids = 0
         self._num_train_cams = 0
@@ -209,21 +220,33 @@ class VideoDataManager(BaseDataManager):
         if image_training:
             # each batch has image data of shape (batch, channel, height, width)
             self.trainloader = DataLoader(
-                ImageDataset(train, transform=self.transform_train), sampler=self.train_sampler,
-                batch_size=self.train_batch_size, shuffle=False, num_workers=self.workers,
-                pin_memory=self.use_gpu, drop_last=True
+                ImageDataset(train, transform=self.transform_train),
+                sampler=self.train_sampler,
+                batch_size=self.train_batch_size,
+                shuffle=False,
+                num_workers=self.workers,
+                pin_memory=self.use_gpu,
+                drop_last=True
             )
         
         else:
             # each batch has image data of shape (batch, seq_len, channel, height, width)
             # note: this requires new training scripts
             self.trainloader = DataLoader(
-                VideoDataset(train, seq_len=self.seq_len, sample_method=self.sample_method, transform=self.transform_train),
-                batch_size=self.train_batch_size, shuffle=True, num_workers=self.workers,
-                pin_memory=self.use_gpu, drop_last=True
+                VideoDataset(
+                    train,
+                    seq_len=self.seq_len,
+                    sample_method=self.sample_method,
+                    transform=self.transform_train
+                ),
+                batch_size=self.train_batch_size,
+                shuffle=True,
+                num_workers=self.workers,
+                pin_memory=self.use_gpu,
+                drop_last=True
             )
 
-        print('=> Initializing TEST (target) datasets')
+        print('=> Initializing test (target) datasets')
         self.testloader_dict = {name: {'query': None, 'gallery': None} for name in target_names}
         self.testdataset_dict = {name: {'query': None, 'gallery': None} for name in target_names}
 
@@ -231,15 +254,31 @@ class VideoDataManager(BaseDataManager):
             dataset = init_vidreid_dataset(root=self.root, name=name, split_id=self.split_id)
 
             self.testloader_dict[name]['query'] = DataLoader(
-                VideoDataset(dataset.query, seq_len=self.seq_len, sample_method=self.sample_method, transform=self.transform_test),
-                batch_size=self.test_batch_size, shuffle=False, num_workers=self.workers,
-                pin_memory=self.use_gpu, drop_last=False,
+                VideoDataset(
+                    dataset.query,
+                    seq_len=self.seq_len,
+                    sample_method=self.sample_method,
+                    transform=self.transform_test
+                ),
+                batch_size=self.test_batch_size,
+                shuffle=False,
+                num_workers=self.workers,
+                pin_memory=self.use_gpu,
+                drop_last=False
             )
 
             self.testloader_dict[name]['gallery'] = DataLoader(
-                VideoDataset(dataset.gallery, seq_len=self.seq_len, sample_method=self.sample_method, transform=self.transform_test),
-                batch_size=self.test_batch_size, shuffle=False, num_workers=self.workers,
-                pin_memory=self.use_gpu, drop_last=False,
+                VideoDataset(
+                    dataset.gallery,
+                    seq_len=self.seq_len,
+                    sample_method=self.sample_method,
+                    transform=self.transform_test
+                ),
+                batch_size=self.test_batch_size,
+                shuffle=False,
+                num_workers=self.workers,
+                pin_memory=self.use_gpu,
+                drop_last=False
             )
 
             self.testdataset_dict[name]['query'] = dataset.query
diff --git a/torchreid/datasets/__init__.py b/torchreid/datasets/__init__.py
index 6d00028..b4f6fa5 100644
--- a/torchreid/datasets/__init__.py
+++ b/torchreid/datasets/__init__.py
@@ -31,7 +31,7 @@ __imgreid_factory = {
     'prid450s': PRID450S,
     'ilids': iLIDS,
     'sensereid': SenseReID,
-    'prid': PRID,
+    'prid': PRID
 }
 
 
@@ -39,17 +39,19 @@ __vidreid_factory = {
     'mars': Mars,
     'ilidsvid': iLIDSVID,
     'prid2011': PRID2011,
-    'dukemtmcvidreid': DukeMTMCVidReID,
+    'dukemtmcvidreid': DukeMTMCVidReID
 }
 
 
 def init_imgreid_dataset(name, **kwargs):
-    if name not in list(__imgreid_factory.keys()):
-        raise KeyError('Invalid dataset, got "{}", but expected to be one of {}'.format(name, list(__imgreid_factory.keys())))
+    avai_datasets = list(__imgreid_factory.keys())
+    if name not in avai_datasets:
+        raise RuntimeError('Invalid dataset name. Received "{}", but expected to be one of {}'.format(name, avai_datasets))
     return __imgreid_factory[name](**kwargs)
 
 
 def init_vidreid_dataset(name, **kwargs):
-    if name not in list(__vidreid_factory.keys()):
-        raise KeyError('Invalid dataset, got "{}", but expected to be one of {}'.format(name, list(__vidreid_factory.keys())))
+    avai_datasets = list(__vidreid_factory.keys())
+    if name not in avai_datasets:
+        raise RuntimeError('Invalid dataset name. Received "{}", but expected to be one of {}'.format(name, avai_datasets))
     return __vidreid_factory[name](**kwargs)
\ No newline at end of file
diff --git a/torchreid/datasets/bases.py b/torchreid/datasets/bases.py
index 9dfb63c..c0b6ddb 100644
--- a/torchreid/datasets/bases.py
+++ b/torchreid/datasets/bases.py
@@ -18,7 +18,59 @@ class BaseDataset(object):
             if not osp.exists(f):
                 raise RuntimeError('"{}" is not found'.format(f))
 
-    def get_imagedata_info(self, data):
+    def extract_data_info(self, data):
+        """Extract info from data list
+
+        Return: num_pids, num_imgs, num_cams, optional
+        """
+        raise NotImplementedError
+
+    def get_num_pids(self, data):
+        return self.extract_data_info(data)[0]
+
+    def get_num_cams(self, data):
+        return self.extract_data_info(data)[2]
+
+    def init_attributes(self, train, query, gallery):
+        self._train = train
+        self._query = query
+        self._gallery = gallery
+        self._num_train_pids = self.get_num_pids(train)
+        self._num_train_cams = self.get_num_cams(train)
+
+    def print_dataset_statistics(self):
+        raise NotImplementedError
+
+    @property
+    def train(self):
+        # train list containing (img_path, pid, camid)
+        return self._train
+
+    @property
+    def query(self):
+        # query list containing (img_path, pid, camid)
+        return self._query
+
+    @property
+    def gallery(self):
+        # gallery list containing (img_path, pid, camid)
+        return self._gallery
+
+    @property
+    def num_train_pids(self):
+        # number of train identities
+        return self._num_train_pids
+
+    @property
+    def num_train_cams(self):
+        # number of train camera views
+        return self._num_train_cams
+
+
+class BaseImageDataset(BaseDataset):
+    """Base class of image-reid dataset"""
+
+    def extract_data_info(self, data):
         pids, cams = [], []
         for _, pid, camid in data:
             pids += [pid]
@@ -30,32 +82,10 @@ class BaseDataset(object):
         num_imgs = len(data)
         return num_pids, num_imgs, num_cams
 
-    def get_videodata_info(self, data, return_tracklet_stats=False):
-        pids, cams, tracklet_stats = [], [], []
-        for img_paths, pid, camid in data:
-            pids += [pid]
-            cams += [camid]
-            tracklet_stats += [len(img_paths)]
-        pids = set(pids)
-        cams = set(cams)
-        num_pids = len(pids)
-        num_cams = len(cams)
-        num_tracklets = len(data)
-        if return_tracklet_stats:
-            return num_pids, num_tracklets, num_cams, tracklet_stats
-        return num_pids, num_tracklets, num_cams
-
-    def print_dataset_statistics(self):
-        raise NotImplementedError
-
-
-class BaseImageDataset(BaseDataset):
-    """Base class of image-reid dataset"""
-
     def print_dataset_statistics(self, train, query, gallery):
-        num_train_pids, num_train_imgs, num_train_cams = self.get_imagedata_info(train)
-        num_query_pids, num_query_imgs, num_query_cams = self.get_imagedata_info(query)
-        num_gallery_pids, num_gallery_imgs, num_gallery_cams = self.get_imagedata_info(gallery)
+        num_train_pids, num_train_imgs, num_train_cams = self.extract_data_info(train)
+        num_query_pids, num_query_imgs, num_query_cams = self.extract_data_info(query)
+        num_gallery_pids, num_gallery_imgs, num_gallery_cams = self.extract_data_info(gallery)
 
         print('=> Loaded {}'.format(self.__class__.__name__))
         print('  ----------------------------------------')
@@ -70,15 +100,30 @@ class BaseImageDataset(BaseDataset):
 class BaseVideoDataset(BaseDataset):
     """Base class of video-reid dataset"""
 
+    def extract_data_info(self, data, return_tracklet_stats=False):
+        pids, cams, tracklet_stats = [], [], []
+        for img_paths, pid, camid in data:
+            pids += [pid]
+            cams += [camid]
+            tracklet_stats += [len(img_paths)]
+        pids = set(pids)
+        cams = set(cams)
+        num_pids = len(pids)
+        num_cams = len(cams)
+        num_tracklets = len(data)
+        if return_tracklet_stats:
+            return num_pids, num_tracklets, num_cams, tracklet_stats
+        return num_pids, num_tracklets, num_cams
+
     def print_dataset_statistics(self, train, query, gallery):
         num_train_pids, num_train_tracklets, num_train_cams, train_tracklet_stats = \
-            self.get_videodata_info(train, return_tracklet_stats=True)
+            self.extract_data_info(train, return_tracklet_stats=True)
         
         num_query_pids, num_query_tracklets, num_query_cams, query_tracklet_stats = \
-            self.get_videodata_info(query, return_tracklet_stats=True)
+            self.extract_data_info(query, return_tracklet_stats=True)
         
         num_gallery_pids, num_gallery_tracklets, num_gallery_cams, gallery_tracklet_stats = \
-            self.get_videodata_info(gallery, return_tracklet_stats=True)
+            self.extract_data_info(gallery, return_tracklet_stats=True)
 
         tracklet_stats = train_tracklet_stats + query_tracklet_stats + gallery_tracklet_stats
         min_num = np.min(tracklet_stats)
diff --git a/torchreid/datasets/cuhk01.py b/torchreid/datasets/cuhk01.py
index 63f5635..c530e94 100644
--- a/torchreid/datasets/cuhk01.py
+++ b/torchreid/datasets/cuhk01.py
@@ -63,17 +63,11 @@ class CUHK01(BaseImageDataset):
         query = [tuple(item) for item in query]
         gallery = [tuple(item) for item in gallery]
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def extract_file(self):
         if not osp.exists(self.campus_dir):
             print('Extracting files')
diff --git a/torchreid/datasets/cuhk03.py b/torchreid/datasets/cuhk03.py
index 71a0e3f..4c8c93f 100644
--- a/torchreid/datasets/cuhk03.py
+++ b/torchreid/datasets/cuhk03.py
@@ -81,17 +81,11 @@ class CUHK03(BaseImageDataset):
         query = split['query']
         gallery = split['gallery']
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def preprocess_split(self):
         """
         This function is a bit complex and ugly, what it does is
diff --git a/torchreid/datasets/dukemtmcreid.py b/torchreid/datasets/dukemtmcreid.py
index 5ed3aec..0f613c1 100644
--- a/torchreid/datasets/dukemtmcreid.py
+++ b/torchreid/datasets/dukemtmcreid.py
@@ -57,17 +57,11 @@ class DukeMTMCreID(BaseImageDataset):
         query = self.process_dir(self.query_dir, relabel=False)
         gallery = self.process_dir(self.gallery_dir, relabel=False)
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def download_data(self):
         if osp.exists(self.dataset_dir):
             return
diff --git a/torchreid/datasets/dukemtmcvidreid.py b/torchreid/datasets/dukemtmcvidreid.py
index 6ca43de..857e2d2 100644
--- a/torchreid/datasets/dukemtmcvidreid.py
+++ b/torchreid/datasets/dukemtmcvidreid.py
@@ -60,17 +60,11 @@ class DukeMTMCVidReID(BaseVideoDataset):
         query = self.process_dir(self.query_dir, self.split_query_json_path, relabel=False)
         gallery = self.process_dir(self.gallery_dir, self.split_gallery_json_path, relabel=False)
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, _, self.num_train_cams = self.get_videodata_info(self.train)
-        self.num_query_pids, _, self.num_query_cams = self.get_videodata_info(self.query)
-        self.num_gallery_pids, _, self.num_gallery_cams = self.get_videodata_info(self.gallery)
-
     def download_data(self):
         if osp.exists(self.dataset_dir):
             return
diff --git a/torchreid/datasets/grid.py b/torchreid/datasets/grid.py
index 68cd458..0bea9d7 100644
--- a/torchreid/datasets/grid.py
+++ b/torchreid/datasets/grid.py
@@ -67,17 +67,11 @@ class GRID(BaseImageDataset):
         query = [tuple(item) for item in query]
         gallery = [tuple(item) for item in gallery]
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def download_data(self):
         if osp.exists(self.dataset_dir):
             return
diff --git a/torchreid/datasets/ilids.py b/torchreid/datasets/ilids.py
index 21f67f6..73eed12 100644
--- a/torchreid/datasets/ilids.py
+++ b/torchreid/datasets/ilids.py
@@ -58,17 +58,11 @@ class iLIDS(BaseImageDataset):
 
         train, query, gallery = self.process_split(split)
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def download_data(self):
         if osp.exists(self.dataset_dir):
             return
diff --git a/torchreid/datasets/ilidsvid.py b/torchreid/datasets/ilidsvid.py
index bcd6197..936751c 100644
--- a/torchreid/datasets/ilidsvid.py
+++ b/torchreid/datasets/ilidsvid.py
@@ -65,17 +65,11 @@ class iLIDSVID(BaseVideoDataset):
         query = self.process_data(test_dirs, cam1=True, cam2=False)
         gallery = self.process_data(test_dirs, cam1=False, cam2=True)
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, _, self.num_train_cams = self.get_videodata_info(self.train)
-        self.num_query_pids, _, self.num_query_cams = self.get_videodata_info(self.query)
-        self.num_gallery_pids, _, self.num_gallery_cams = self.get_videodata_info(self.gallery)
-
     def download_data(self):
         if osp.exists(self.dataset_dir):
             return
diff --git a/torchreid/datasets/market1501.py b/torchreid/datasets/market1501.py
index 25bfb72..669b2a6 100644
--- a/torchreid/datasets/market1501.py
+++ b/torchreid/datasets/market1501.py
@@ -57,17 +57,11 @@ class Market1501(BaseImageDataset):
         if self.market1501_500k:
             gallery += self.process_dir(self.extra_gallery_dir, relabel=False)
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def process_dir(self, dir_path, relabel=False):
         img_paths = glob.glob(osp.join(dir_path, '*.jpg'))
         pattern = re.compile(r'([-\d]+)_c(\d)')
diff --git a/torchreid/datasets/mars.py b/torchreid/datasets/mars.py
index 1af5d25..12e00d6 100644
--- a/torchreid/datasets/mars.py
+++ b/torchreid/datasets/mars.py
@@ -66,17 +66,11 @@ class Mars(BaseVideoDataset):
         query = self.process_data(test_names, track_query, home_dir='bbox_test', relabel=False, min_seq_len=min_seq_len)
         gallery = self.process_data(test_names, track_gallery, home_dir='bbox_test', relabel=False, min_seq_len=min_seq_len)
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, _, self.num_train_cams = self.get_videodata_info(self.train)
-        self.num_query_pids, _, self.num_query_cams = self.get_videodata_info(self.query)
-        self.num_gallery_pids, _, self.num_gallery_cams = self.get_videodata_info(self.gallery)
-
     def get_names(self, fpath):
         names = []
         with open(fpath, 'r') as f:
diff --git a/torchreid/datasets/msmt17.py b/torchreid/datasets/msmt17.py
index 6007376..ce629aa 100644
--- a/torchreid/datasets/msmt17.py
+++ b/torchreid/datasets/msmt17.py
@@ -84,17 +84,10 @@ class MSMT17(BaseImageDataset):
         #train += val
         #num_train_imgs += num_val_imgs
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
-
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def process_dir(self, dir_path, list_path):
         with open(list_path, 'r') as txt:
             lines = txt.readlines()
diff --git a/torchreid/datasets/prid.py b/torchreid/datasets/prid.py
index 151873c..13538c9 100644
--- a/torchreid/datasets/prid.py
+++ b/torchreid/datasets/prid.py
@@ -60,17 +60,11 @@ class PRID(BaseImageDataset):
 
         train, query, gallery = self.process_split(split)
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def prepare_split(self):
         if not osp.exists(self.split_path):
             print('Creating splits ...')
diff --git a/torchreid/datasets/prid2011.py b/torchreid/datasets/prid2011.py
index d5b3050..6b95317 100644
--- a/torchreid/datasets/prid2011.py
+++ b/torchreid/datasets/prid2011.py
@@ -58,17 +58,11 @@ class PRID2011(BaseVideoDataset):
         query = self.process_dir(test_dirs, cam1=True, cam2=False)
         gallery = self.process_dir(test_dirs, cam1=False, cam2=True)
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, _, self.num_train_cams = self.get_videodata_info(self.train)
-        self.num_query_pids, _, self.num_query_cams = self.get_videodata_info(self.query)
-        self.num_gallery_pids, _, self.num_gallery_cams = self.get_videodata_info(self.gallery)
-
     def process_dir(self, dirnames, cam1=True, cam2=True):
         tracklets = []
         dirname2pid = {dirname:i for i, dirname in enumerate(dirnames)}
diff --git a/torchreid/datasets/prid450s.py b/torchreid/datasets/prid450s.py
index 437a3aa..60e1f6b 100644
--- a/torchreid/datasets/prid450s.py
+++ b/torchreid/datasets/prid450s.py
@@ -65,17 +65,11 @@ class PRID450S(BaseImageDataset):
         query = [tuple(item) for item in query]
         gallery = [tuple(item) for item in gallery]
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def download_data(self):
         if osp.exists(self.dataset_dir):
             return
diff --git a/torchreid/datasets/sensereid.py b/torchreid/datasets/sensereid.py
index 337d3c0..7d38487 100644
--- a/torchreid/datasets/sensereid.py
+++ b/torchreid/datasets/sensereid.py
@@ -52,17 +52,12 @@ class SenseReID(BaseImageDataset):
 
         query = self.process_dir(self.query_dir)
         gallery = self.process_dir(self.gallery_dir)
+        train = copy.deepcopy(query) # dummy variable
+
+        self.init_attributes(train, query, gallery)
 
         if verbose:
-            self.print_dataset_statistics(query, query, gallery)
-
-        self.train = copy.deepcopy(query) # only used to initialize trainloader
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
+            self.print_dataset_statistics(train, query, gallery)
 
     def process_dir(self, dir_path):
         img_paths = glob.glob(osp.join(dir_path, '*.jpg'))
diff --git a/torchreid/datasets/viper.py b/torchreid/datasets/viper.py
index 05a777a..fbc0598 100755
--- a/torchreid/datasets/viper.py
+++ b/torchreid/datasets/viper.py
@@ -64,17 +64,11 @@ class VIPeR(BaseImageDataset):
         query = [tuple(item) for item in query]
         gallery = [tuple(item) for item in gallery]
 
+        self.init_attributes(train, query, gallery)
+
         if verbose:
             self.print_dataset_statistics(train, query, gallery)
 
-        self.train = train
-        self.query = query
-        self.gallery = gallery
-
-        self.num_train_pids, self.num_train_imgs, self.num_train_cams = self.get_imagedata_info(self.train)
-        self.num_query_pids, self.num_query_imgs, self.num_query_cams = self.get_imagedata_info(self.query)
-        self.num_gallery_pids, self.num_gallery_imgs, self.num_gallery_cams = self.get_imagedata_info(self.gallery)
-
     def download_data(self):
         if osp.exists(self.dataset_dir):
             return