An Overview of Image Caption Generation Methods In recent years, with the rapid development of artificial intelligence, image caption has gradually attracted the attention of many researchers in the field of artificial intelligence and has become an interesting and arduous task. Image caption, automatically generating natural language descriptions according to the content observed in an image, is an important part of scene understanding, which combines the knowledge of computer vision and natural language processing. The application of image caption is extensive and significant, for example, the realization of humancomputer interaction. This paper summarizes the related methods and focuses on the attention mechanism, which plays an important role in computer vision and is recently widely used in image caption generation tasks. Furthermore, the advantages and the shortcomings of these methods are discussed, providing the commonly used datasets and evaluation criteria in this field. Finally, this paper highlights some open challenges in the image caption task.

Attention Analysis in Caption Generation Caption Generation is one of the fundamental tasks combining computer vision and natural language processing. To achieve this goal, neural networks are employed to implement a caption generation system. In this paper, we proposed a caption generation system combining a CNNbased object detection system and a language model with a recurrent neural network. Especially, a vector which is sent from the object detection system to the language model is generated using an attention mechanism. Attention visualization can help us to understand the system focuses on a part of the input image in generating a caption. In the experiments, we evaluate the performance of the proposed system and discuss the effects of the attention mechanism in the image caption. Especially, the attention contributes to the improvement of caption generation but the attention is uncorrelated to system interpretation.