add dataset_root judgment

dygraph/datasets/ade.py

@@ -58,6 +58,9 @@ class ADE20K(Dataset):
                 savepath=DATA_HOME,
                 extrapath=DATA_HOME,
                 extraname='ADEChallengeData2016')
+        elif not os.path.exists(self.dataset_root):
+            raise Exception('there is not dataset_root: {}.'.format(
+                self.dataset_root))
 
         if mode == 'train':
             img_dir = os.path.join(self.dataset_root, 'images/training')

dygraph/datasets/dataset.py

@@ -66,6 +66,10 @@ class Dataset(fluid.io.Dataset):
             raise Exception("transforms is necessary, but it is None.")
 
         self.dataset_root = dataset_root
+        if not os.path.exists(self.dataset_root):
+            raise Exception('there is not dataset_root: {}.'.format(
+                self.dataset_root))
+
         if mode == 'train':
             if train_list is None:
                 raise Exception(

dygraph/datasets/optic_disc_seg.py

@@ -46,6 +46,9 @@ class OpticDiscSeg(Dataset):
                 raise Exception("data_file not set and auto download disabled.")
             self.dataset_root = download_file_and_uncompress(
                 url=URL, savepath=DATA_HOME, extrapath=DATA_HOME)
+        elif not os.path.exists(self.dataset_root):
+            raise Exception('there is not dataset_root: {}.'.format(
+                self.dataset_root))
 
         if mode == 'train':
             file_list = os.path.join(self.dataset_root, 'train_list.txt')

dygraph/datasets/voc.py

@@ -58,6 +58,9 @@ class PascalVOC(Dataset):
                 savepath=DATA_HOME,
                 extrapath=DATA_HOME,
                 extraname='VOCdevkit')
+        elif not os.path.exists(self.dataset_root):
+            raise Exception('there is not dataset_root: {}.'.format(
+                self.dataset_root))
 
         image_set_dir = os.path.join(self.dataset_root, 'VOC2012', 'ImageSets',
                                      'Segmentation')