def __init__(self, mongo_collection, base_directory):
        """Initialize the MongoDB collection and base directory where to store
        images files. Set immutable and mandatory properties.

        Parameters
        ----------
        mongo_collection : Collection
            Collection in MongoDB storing image information
        base_directory : string
            Base directory on local disk for image files. Files are stored
            in sub-directories named by the subject identifier. To avoid having
            too many files in a single directory we group these sub-directories
            in directories that start with the first two characters of the
            object identifier.
        """
        # Initialize the super class
        super(DefaultImageManager, self).__init__(
            mongo_collection,
            base_directory,
            [
                datastore.PROPERTY_FILENAME,
                datastore.PROPERTY_FILESIZE,
                datastore.PROPERTY_MIMETYPE
            ]
        )
def __init__ ( self , mongo_collection , base_directory ) : super ( DefaultImageManager , self ) . __init__ ( mongo_collection , base_directory , [ datastore . PROPERTY_FILENAME , datastore . PROPERTY_FILESIZE , datastore . PROPERTY_MIMETYPE ] )
Initialize the MongoDB collection and base directory where to store
        images files. Set immutable and mandatory properties.

        Parameters
        ----------
        mongo_collection : Collection
            Collection in MongoDB storing image information
        base_directory : string
            Base directory on local disk for image files. Files are stored
            in sub-directories named by the subject identifier. To avoid having
            too many files in a single directory we group these sub-directories
            in directories that start with the first two characters of the
            object identifier.