Using Computer Vision Technologies to Make the Virtual Visible

Augmented reality (AR) applications typically overlay LQIRUPDWLRQDERXWWKHXVHU∂VHQYLURQPHQWLQWKHLUPRELOH� SKRQH∂VFDPHUDYLHZ��5DWKHUWKDQRQO\�XVL ng the camera view as a backdrop f or information presentation, however, AR applications could also benefit from using the camera as a sensor to a greater extent . Beyond using visual data for markerless tracking, AR applications could recognize objects and provide users with information based on these objects. We present two applications that use the camera as a sensor: Pic ⴀ in and SubwayArt . The first allo ws users to check ⴀ in on location ⴀ sharing service foursquare by taking a picture of the venue they are at. The second provides users with information about artworks in the Stockholm subway system by combining localization and computer vision techniques.