Users plan optimization for participatory urban texture documentation

We envision participatory texture documentation (PTD) as a process in which a group of users (dedicated individuals and/or general public) with cameraequipped mobile phones participate in collaborative collection of urban texture information. PTD enables inexpensive, scalable and high quality urban texture documentation. We propose to implement PTD in two steps. At the first step, termed viewpoint selection, a minimum number of viewpoints in the urban environment are selected from which the texture of the entire urban environment (the part visible to cameras) with a desirable quality can be collected/captured. At the second step, called viewpoint assignment, the selected viewpoints are assigned to the participating users such that given a limited number of users with various constraints (e.g., restricted available time) users can collectively capture the maximum amount of texture information within a limited time interval. In this paper, we define each of these steps and prove that both are NP-hard problems. Accordingly, we propose efficient algorithms to implement the viewpoint selection and assignment problems. This research has been funded in part by NSF grant CNS0831505 (CyberTrust), the NSF Integrated Media Systems Center (IMSC), the NSF Center for Embedded Networked Sensing (CENS), and in part by unrestricted cash and equipment gift from Google and Microsoft. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. H. Shirani-Mehr (B) · F. Banaei-Kashani · C. Shahabi Department of Computer Science, University of Southern California, Los Angeles, CA 90089, USA e-mail: [email protected] F. Banaei-Kashani e-mail: [email protected] C. Shahabi e-mail: [email protected]