'basic information about an image database
:param name: name of image database will be used for any output
:param root_path: root path store cache and proposal data
:param dataset_path: dataset path store images and image lists'

def __init__(self, name, image_set, root_path, dataset_path):

    self.name = ((name + '_') + image_set)
    self.image_set = image_set
    self.root_path = root_path
    self.data_path = dataset_path
    self.classes = []
    self.num_classes = 0
    self.image_set_index = []
    self.num_images = 0
    self.config = {}
