Error when trying to visualize synthetic dataset

[tensarflow]

Hey everyone!

Thanks for the great work and thanks for sharing the code.

I have an issue when trying to visualize the dataset I generated synthetically with the synthetic data generation tool provided by this repo. I run the notebook inspect_dataset and get following error in the second cell:

---------------------------------------------------------------------------
ConstructorError                          Traceback (most recent call last)
Cell In [5], line 3
      1 # ds_name = 'ycbv.train.real'
      2 ds_name = 'synthetic.ycbv-1M.train'
----> 3 scene_ds = make_scene_dataset(ds_name)

File ~/cosypose/cosypose/datasets/datasets_cfg.py:139, in make_scene_dataset(ds_name, n_frames)
    137     is_train = 'train' in ds_name.split('.')[-1]
    138     ds_name = ds_name.split('.')[1]
--> 139     ds = SyntheticSceneDataset(ds_dir=LOCAL_DATA_DIR / 'synt_datasets' / ds_name, train=is_train)
    141 else:
    142     raise ValueError(ds_name)

File ~/cosypose/cosypose/datasets/synthetic_dataset.py:22, in SyntheticSceneDataset.__init__(self, ds_dir, train)
     20 keys_path = ds_dir / (('train' if train else 'val') + '_keys.pkl')
     21 keys = pkl.loads(keys_path.read_bytes())
---> 22 self.cfg = yaml.load((ds_dir / 'config.yaml').read_text(), Loader=yaml.FullLoader)
     23 self.object_set = self.cfg.scene_kwargs['urdf_ds']
     24 self.keys = keys

File ~/anaconda3/envs/cosypose/lib/python3.10/site-packages/yaml/__init__.py:81, in load(stream, Loader)
     79 loader = Loader(stream)
     80 try:
---> 81     return loader.get_single_data()
     82 finally:
     83     loader.dispose()

File ~/anaconda3/envs/cosypose/lib/python3.10/site-packages/yaml/constructor.py:51, in BaseConstructor.get_single_data(self)
     49 node = self.get_single_node()
     50 if node is not None:
---> 51     return self.construct_document(node)
     52 return None

File ~/anaconda3/envs/cosypose/lib/python3.10/site-packages/yaml/constructor.py:55, in BaseConstructor.construct_document(self, node)
     54 def construct_document(self, node):
---> 55     data = self.construct_object(node)
     56     while self.state_generators:
     57         state_generators = self.state_generators

File ~/anaconda3/envs/cosypose/lib/python3.10/site-packages/yaml/constructor.py:100, in BaseConstructor.construct_object(self, node, deep)
     98             constructor = self.__class__.construct_mapping
     99 if tag_suffix is None:
--> 100     data = constructor(self, node)
    101 else:
    102     data = constructor(self, tag_suffix, node)

File ~/anaconda3/envs/cosypose/lib/python3.10/site-packages/yaml/constructor.py:427, in SafeConstructor.construct_undefined(self, node)
    426 def construct_undefined(self, node):
--> 427     raise ConstructorError(None, None,
    428             "could not determine a constructor for the tag %r" % node.tag,
    429             node.start_mark)

ConstructorError: could not determine a constructor for the tag 'tag:yaml.org,2002:python/object:argparse.Namespace'
  in "<unicode string>", line 1, column 1:
    !!python/object:argparse.Namespace
    ^

I think there is a problem with the structure of the YAML file. When I delete !!python/object:argparse.Namespace in the first line and !!python/object/apply:pathlib.PosixPath in the third line inside the YAML file of the dataset, I get following error:

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
Cell In [6], line 3
      1 # ds_name = 'ycbv.train.real'
      2 ds_name = 'synthetic.ycbv-1M.train'
----> 3 scene_ds = make_scene_dataset(ds_name)

File ~/cosypose/cosypose/datasets/datasets_cfg.py:139, in make_scene_dataset(ds_name, n_frames)
    137     is_train = 'train' in ds_name.split('.')[-1]
    138     ds_name = ds_name.split('.')[1]
--> 139     ds = SyntheticSceneDataset(ds_dir=LOCAL_DATA_DIR / 'synt_datasets' / ds_name, train=is_train)
    141 else:
    142     raise ValueError(ds_name)

File ~/cosypose/cosypose/datasets/synthetic_dataset.py:23, in SyntheticSceneDataset.__init__(self, ds_dir, train)
     21 keys = pkl.loads(keys_path.read_bytes())
     22 self.cfg = yaml.load((ds_dir / 'config.yaml').read_text(), Loader=yaml.FullLoader)
---> 23 self.object_set = self.cfg.scene_kwargs['urdf_ds']
     24 self.keys = keys
     26 urdf_ds_name = self.cfg.scene_kwargs['urdf_ds']

AttributeError: 'dict' object has no attribute 'scene_kwargs'

When I try to validate the content of the YAML file with https://codebeautify.org/yaml-validator, I get errors in both versions. I think there is something with the !! expressions. While python seems to not have a problem with these expressions when I remove the two lines mentioned above, but rather has a problem with the content of file, it cant find the scene_kwargs attribute.

Any help is appreciated. Thanks in advance

[JHRosskamp]

Hi @tensarflow,
I had the same error. To fix it, change
self.cfg = yaml.load((ds_dir / 'config.yaml').read_text(), Loader=yaml.FullLoader)
to
self.cfg = yaml.load((ds_dir / 'config.yaml').read_text(), Loader=yaml.UnsafeLoader)
in datasets/synthetic_dataset.py.

It works with the provided YAML file and you don't have to delete any lines in the files.