extCaps requires models to read and reason about text in images to generate captions about them. Specifically, models need to incorporate a new modality of text present in the images and reason over it and visual content in the image to generate image descriptions.
Current state-of-the-art models fail to generate captions for images in TextCaps because they do not have text reading and reasoning capabilities. See the examples in the image to compare ground truth answers and corresponding predictions by a state-of-the-art model.