Image-Text Surgery: Efficient Concept Learning in Image Captioning by Generating Pseudopairs.

Abstract

Image captioning aims to generate natural language sentences to describe the salient parts of a given image. Although neural networks have recently achieved promising results, a key problem is that they can only describe concepts seen in the training image-sentence pairs. Efficient learning of novel concepts has thus been a topic of recent interest to alleviate the expensive manpower of labeling data. In this paper, we propose a novel method, Image-Text Surgery, to synthesize pseudoimage-sentence pairs. The pseudopairs are generated under the guidance of a knowledge base, with syntax from a seed data set (i.e., MSCOCO) and visual information from an existing large-scale image base (i.e., ImageNet). Via pseudodata, the captioning model learns novel concepts without any corresponding human-labeled pairs. We further introduce adaptive visual replacement, which adaptively filters unnecessary visual features in pseudodata with an attention mechanism. We evaluate our approach on a held-out subset of the MSCOCO data set. The experimental results demonstrate that the proposed approach provides significant performance improvements over state-of-the-art methods in terms of F1 score and sentence quality. An ablation study and the qualitative results further validate the effectiveness of our approach.