Transductive Cross-Lingual Scene-Text Visual Question Answering

Multilingual modeling has gained increasing attention in recent years, as the cross-lingual Text-based Visual Question Answering (TextVQA) are requried to understand questions and answers across different languages. Current researches mainly work on multimodal information assuming that multilingual pretrained models are effective to encode questions. However, the semantic comprehension of a text-based question varies between languages, creating challenges in directly deducing its answer from an image. To this end, we propose a novel multilingual text-based VQA framework suited for cross-language scenarios(CLVQA), transductively considering multiple answer generating interactions with questions. First, a question reading module densely connects encoding layers in a feedforward manner, which can adaptively work together with answering. Second, a multimodal OCR-based module decouples OCR features in an image into visual, linguistic, and holistic parts to facilitate the localization of a target-language answer. By incorporating enhancements from the above two input encoding modules, the proposed framework outputs its answer candidates mainly from the input image with a object detection module. Finally, a transductive answering module jointly understands input multimodal information and identified answer candidates at the multilingual level, autoregressively generating cross-lingual answers. Extensive experiments show that our framework outperforms state-of-the-art methods for both of cross-lingual (English \({<}\) - \({>}\) Chinese) and mono-lingual (English \({<}\) - \({>}\) English and Chinese \({<}\) - \({>}\) Chinese) tasks in terms of accuracy based metrics. Moreover, significant improvements are achieved in zero-shot cross-lingual settings(French \({<}\) - \({>}\) Chinese).