'wrapper for im_detect and visualize_detection
Parameters:
im_list : list of str or str
image path or list of image paths
root_dir : str or None
directory of input images, optional if image path already
has full directory information
extension : str or None
image extension, eg. ".jpg", optional
Returns:'

def detect_and_visualize(self, im_list, root_dir=None, extension=None, classes=[], thresh=0.6, show_timer=False):

    import cv2
    dets = self.im_detect(im_list, root_dir, extension, show_timer=show_timer)
    if (not isinstance(im_list, list)):
        im_list = [im_list]
    assert (len(dets) == len(im_list))
    for (k, det) in enumerate(dets):
        img = cv2.imread(im_list[k])
        img[:, :, (0, 1, 2)] = img[:, :, (2, 1, 0)]
        self.visualize_detection(img, det, classes, thresh)
