Slidecho: Flexible Non-Visual Exploration of
Presentation Videos

Carnegie Mellon University | Human-Computer Interaction Institute

Abstract

We present Slidecho, a system that enables non-visual access of the slide content in a presentation video on-demand. Slidecho automatically extracts slides and their text and image elements from the presentation video and aligns these elements to the presenter’s speech. When listening to the video, Slidecho provides learners with audio notifications about slide changes and slide elements that are not described by the presenter. The learner can pause the video and browse the entire slide, or only the undescribed slide elements, to gain information. A technical evaluation with presentation videos in-the-wild shows that compared to the presenter’s speech alone, Slidecho provides access to an additional 20% of total text elements and 30% of total image elements that were previously not described. Blind and visually impaired participants in our user study reported that it was easier to locate undescribed slide elements with Slidecho’s synchronized interface than when browsing the video and extracted slides separately, and using Slidecho they read fewer slides that were fully redundant with the speech.