How to add new operation for mmdetection

Hey! I implement a ROI pooling operation according to /mmcv/ops/deform_roi_pool.py. Then I recompile the whole library from the source, and I could use this module by calling “from mmcv.ops import xxx” now. However, when I try to use this operation in mmdetection, the program exits with an AssertionError like this:

cfg = { 'roi_layer': {'output_size': 7, 'sampling_ratio': 0, 'type': 'NewROI'}, 'type': 'SingleRoIExtractor'}
registry = Registry(name=roi_extractor, items={'GenericRoIExtractor': <class 'mmdet.models.roi_heads.roi_extractors.generic_roi_e..., 'SingleRoIExtractor': <class 'mmdet.models.roi_heads.roi_extractors.single_level_roi_extractor.SingleRoIExtractor'>})
default_args = None

    def build_from_cfg(cfg, registry, default_args=None):
        """Build a module from config dict.
    
        Args:
            cfg (dict): Config dict. It should at least contain the key "type".
            registry (:obj:`Registry`): The registry to search the type from.
            default_args (dict, optional): Default initialization arguments.
    
        Returns:
            object: The constructed object.
        """
        if not isinstance(cfg, dict):
            raise TypeError(f'cfg must be a dict, but got {type(cfg)}')
        if 'type' not in cfg:
            if default_args is None or 'type' not in default_args:
                raise KeyError(
                    '`cfg` or `default_args` must contain the key "type", '
                    f'but got {cfg}\n{default_args}')
        if not isinstance(registry, Registry):
            raise TypeError('registry must be an mmcv.Registry object, '
                            f'but got {type(registry)}')
        if not (isinstance(default_args, dict) or default_args is None):
            raise TypeError('default_args must be a dict or None, '
                            f'but got {type(default_args)}')
    
        args = cfg.copy()
    
        if default_args is not None:
            for name, value in default_args.items():
                args.setdefault(name, value)
    
        obj_type = args.pop('type')
        if isinstance(obj_type, str):
            obj_cls = registry.get(obj_type)
            if obj_cls is None:
                raise KeyError(
                    f'{obj_type} is not in the {registry.name} registry')
        elif inspect.isclass(obj_type):
            obj_cls = obj_type
        else:
            raise TypeError(
                f'type must be a str or valid type, but got {type(obj_type)}')
        try:
            return obj_cls(**args)
        except Exception as e:
            # Normal TypeError does not print class name.
>           raise type(e)(f'{obj_cls.__name__}: {e}')
E           AssertionError: SingleRoIExtractor:

../../miniconda3/envs/open-mmlab/lib/python3.7/site-packages/mmcv/utils/registry.py:182: AssertionError

Is there any other config I should change, like the adding ‘.register_module’ or so on? Great thanks for your help!!

[hugoycj]

Yeap. I have resolved this issue. I found that it’s because of the conda environment. I install mmcv-full in another conda environment and it’s strange that each time I try to import mmcv, it’s from that environment instead of my current one. I solve this problem by uninstall all the mmcv on my laptop and recompile it from the source. Great thanks for your help!

[zhouzaida]

Thanks for your feedback.