show_one_labeled_video_frame.py 文件源码

def dump_one_lmdb(path, offset):
    with lmdb.open(path, map_size=map_size) as env, \
            env.begin().cursor() as lmdb_cursor:
        num_entries = env.stat()['entries']
        # Unfortunately, it seems the only way to set the cursor to an
        # arbitrary key index (without knowing the key) is to literally call
        # next() repeatedly.
        lmdb_cursor.next()
        for i in tqdm(range(offset)):
            lmdb_cursor.next()
        video_frame = video_frames_pb2.LabeledVideoFrame()
        video_frame.ParseFromString(lmdb_cursor.value())
        image_proto = video_frame.frame.image
        image = np.fromstring(image_proto.data,
                              dtype=np.uint8).reshape(
                                  image_proto.channels, image_proto.height,
                                  image_proto.width).transpose((1, 2, 0))
        image = Image.fromarray(image, 'RGB')
        image.save('tmp.png')
        print(lmdb_cursor.key())
        print(', '.join([label.name for label in video_frame.label]))