OCR-oriented Master Object for Text Image Captioning

Text image captioning aims to understand the scene text in images for image caption generation. The key issue of this challenging task is to understand the relationship between the text OCR tokens and images. In this paper, we propose a novel text image captioning method by purifying the OCR-oriented scene graph with the master object. The master object is the object to which the OCR is attached, which is the semantic relationship bridge between the OCR token and the image. We consider the master object as a proxy to connect OCR tokens and other regions in the image. By exploring the master object for each OCR token, we build the purified scene graph based on the master objects and then enrich the visual embedding by the Graph Convolution Network (GCN). Furthermore, we cluster the OCR tokens and feed the hierarchical information to provide a richer representation. Experiments on the TextCaps validation and test dataset demonstrate the effectiveness of the proposed method.