Network-Adaptive Image and Video Transmission in Camera-Based Wireless Sensor Networks

We investigate image and video transmission in camera-based wireless sensor networks (WSNs). Our objective is to design a mechanism that finds the transmission strategies that maximize the expected reconstruction quality of the transmitted data at the base station while making efficient use of the limited resources of the WSN. Our approach is based on quality-scalable coding and multipath transmission. Unlike conventional approaches where data is sent over the paths regardless of its importance at the destination, we propose a network-adaptive transmission mechanism that decomposes the source bitstream into segments of unequal importance and reserves the most reliable paths to transmit the segments with the highest importance. Moreover, we use unequal segment loss protection with erasure codes of different strengths to maximize the expected quality at the destination and propose a fast algorithm that finds nearly optimal transmission strategies. We also present simulation results using a test video sequence that show that the proposed transmission mechanism provides adaptability to the time and space varying conditions of camera-based wireless sensor networks.