Guided Text Spotting for Assistive Blind Navigation in Unfamiliar Indoor Environments.

Scene text in indoor environments usually preserves and communicates important contextual information which can significantly enhance the independent travel of blind and visually impaired people. In this paper, we present an assistive text spotting navigation system based on an RGB-D mobile device for blind or severely visually impaired people. Specifically, a novel spatial-temporal text localization algorithm is proposed to localize and prune text regions, by integrating stroke-specific features with a subsequent text tracking process. The density of extracted text-specific feature points serves as an efficient text indicator to guide the user closer to text-likely regions for better recognition performance. Next, detected text regions are binarized and recognized by off-the-shelf optical character recognition methods. Significant non-text indicator signage can also be matched to provide additional environment information. Both recognized results are then transferred to speech feedback for user interaction. Our proposed video text localization approach is quantitatively evaluated on the ICDAR 2013 dataset, and the experimental results demonstrate the effectiveness of our proposed method.