'wrapper for detecting multiple images
Parameters:
im_list : list of str
image path or list of image paths
root_dir : str
directory of input images, optional if image path already
has full directory information
extension : str
image extension, eg. ".jpg", optional
Returns:
list of detection results in format [det0, det1...], det is in
format np.array([id, score, xmin, ymin, xmax, ymax]...)'

def im_detect(self, im_list, root_dir=None, extension=None, show_timer=False):

    test_db = TestDB(im_list, root_dir=root_dir, extension=extension)
    test_iter = DetIter(test_db, 1, self.data_shape, self.mean_pixels, is_train=False)
    return self.detect(test_iter, show_timer)
