Quality-of-service guarantees for wireless computer vision

This paper describes a cost effective and scalable design for a distributed active vision system that consists of mobile cameras, a cluster of high-performance workstations interconnected by a high bandwidth network, and a wireless LAN that connects mobile cameras with the computing cluster. The goal is to support a wireless vision platform that can quickly be moved within a large wireless cell-space by hand, via remote control, or autonomously. The vision algorithms are redesigned to minimize the hardware needed on the mobile platform, and to make us of a distributed network of high-speed nodes accessible by the wireless host machine. This work addresses three problem areas in a distributed active vision system: the design of distributed algorithms for real-time vision processing, the need for network protocol support to achieve real-time guarantees across the wireless network connection, and development of a distributed processing framework. In particular, we present designs to address three aspects of the wireless network protocol problem: providing deterministic guarantees over a multiple access wireless channel, efficient recovery from lost or corrupted packets, and synchronization of video streams. We use active stereo vision and dynamic focus control as examples of the kind of vision tasks that can be supported by this environment.