Low-cost prioritization of image blocks in wireless sensor networks for border surveillance
详细信息   
摘要
Wireless Sensor Networks (WSNs) are becoming more imperative in monitoring and surveillance applications, such as border surveillance. For these applications, cameras attached on several sensor nodes are placed on preselected locations in the border region. In case of an intrusion event, these cameras capture images and transmit them to the sink node via other sensor nodes. WSNs operate with limited resources. Therefore, resource utilization is needed when processing and transporting images. In this study, we propose a cost-effective method for dynamic (on-the-fly) prioritization of image macro-blocks. Therefore, we employ a simple encoding scheme at the source node by labeling data blocks as 鈥渋mportant鈥?and 鈥渘ot-important鈥?based on the information they contain. The network then transmits 鈥渋mportant鈥?data blocks from reliable paths. We established an experimental setup to assess the success of the proposed method using various prioritization measures for labeling and we compared the results with JPEG encoding. The results indicate the usefulness of the proposed prioritization based encoding scheme in terms of transferred image quality, delay and energy.