Computer Science Department
School of Computer Science, Carnegie Mellon University
A Contact Sheet Approach to
Jan Harkes, Mahadev Satyanarayanan,
We describe a cloud-based approach to opportunistic, crowd-sourced, near real-time search of untagged images on smartphones that is sensitive to bandwidth and energy constraints. Our approach is inspired by the long-established practice of photographers using contact sheets to rapidly visualize a new collection of photographs, and then selecting a subset on which to focus attention. On behalf of each smartphone, the cloud maintains a virtual contact sheet of images that have been captured but not yet uploaded. The virtual contact sheet consists of thumbnails as well as full or partial meta data associated with the image. If search processing on the cloud indicates that a particular thumbnail is relevant, then its full-fidelity image can be obtained from the corresponding smartphone for further search processing or presentation to the user. We identify refinements, design tradeoffs and research questions pertaining to this approach.