  Image captioning is currently a challenging task that requires the ability to
both understand visual information and use human language to describe this
visual information in the image. In this paper, we propose an efficient way to
improve the image understanding ability of transformer-based method by
extending Object Relation Transformer architecture with Attention on Attention
mechanism. Experiments on the VieCap4H dataset show that our proposed method
significantly outperforms its original structure on both the public test and
private test of the Image Captioning shared task held by VLSP.
