VizLens: A Robust and Interactive Screen Reader for Interfaces in the Real World

The world is full of physical interfaces that are inaccessible to blind people, from microwaves and information kiosks to thermostats and checkout terminals. Blind people cannot independently use such devices without at least first learning their layout, and usually only after labeling them with sighted assistance. We introduce VizLens - an accessible mobile application and supporting backend that can robustly and interactively help blind people use nearly any interface they encounter. VizLens users capture a photo of an inaccessible interface and send it to multiple crowd workers, who work in parallel to quickly label and describe elements of the interface to make subsequent computer vision easier. The VizLens application helps users recapture the interface in the field of the camera, and uses computer vision to interactively describe the part of the interface beneath their finger (updating 8 times per second). We show that VizLens provides accurate and usable real-time feedback in a study with 10 blind participants, and our crowdsourcing labeling workflow was fast (8 minutes), accurate (99.7%), and cheap ($1.15). We then explore extensions of VizLens that allow it to (i) adapt to state changes in dynamic interfaces, (ii) combine crowd labeling with OCR technology to handle dynamic displays, and (iii) benefit from head-mounted cameras. VizLens robustly solves a long-standing challenge in accessibility by deeply integrating crowdsourcing and computer vision, and foreshadows a future of increasingly powerful interactive applications that would be currently impossible with either alone.