def load_image(video_id, video_frame, image_dir):
    img_path = f'{image_dir}/video_{video_id}/{video_frame}.jpg'
    assert os.path.exists(img_path), f'{img_path} does not exist.'
    img = cv2.imread(img_path)
    return img
def load_image(video_id, video_frame, image_dir):
    img_path = f'{image_dir}/video_{video_id}/{video_frame}.jpg'
    assert os.path.exists(img_path), f'{img_path} does not exist.'
    img = cv2.imread(img_path)
    return img