Research Article
Power Efficient Clustering for Wireless Multimedia
Sensor Network
Seng-Kyoun Jo,
1
Muhammad Ikram,
2
Ilgu Jung,
1
Won Ryu,
1
and Jinsul Kim
3
1
ETRI, 218 Gajeong-ro, Yuseong-gu, Daejeon 305-700, Republic of Korea
2
Darmstadt University of Technology, Hochschulstraße 10, 64289 Darmstadt, Germany
3
Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea
Correspondence should be addressed to Jinsul Kim; jsworld@jnu.ac.kr
Received 4 January 2014; Accepted 20 February 2014; Published 2 April 2014
Academic Editor: Sabah Mohammed
Copyright © 2014 Seng-Kyoun Jo et al. Tis is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Te availability of inexpensive hardware such as CMOS cameras and microphones has fostered the development of wireless
multimedia sensor networks (WMSNs). In WMSNs, wirelessly interconnected devices enable ubiquitously retrieving multimedia
contents such as video and audio streams, and still images along with scalar data from surroundings for wide range of applications
are constrained by processing, memory, and power resources. Image compression via low-complexity and resource efcient
transforms has been addressed by several researchers to prolong network lifetime where energy conservation is achieved through
sharing computational load among sensor nodes and by adjusting the transmission ranges of camera nodes. However, those schemes
are not adaptive to the presence and changes of energy level of computational sensor nodes and to the amount of computational
load. We propose a resource and energy efcient distributed image compression algorithm that dynamically confgures according
to the energy levels and the forwarding strategy that is based on the entropy of the image. Te simulation results show that our
adaptive distributed image compression scheme signifcantly prolongs the network lifetime and improves the network utilization
efciency, while maintaining adequate image quality.
1. Introduction
A wireless multimedia sensor network (WMSN) consists of
sensor nodes deployed over a geographical area for monitor-
ing physical phenomena like temperature, humidity, vibra-
tions, seismic events, and so forth [1]. In WMSNs, a sensor
node is a tiny device that includes three basic components:
a sensing subsystem for data acquisition from the physical
surrounding environment, a processing subsystem for local
data processing and storage, and a wireless communication
subsystem for data transmission. Moreover, a power source
supplies the energy needed by the device to perform the
sensing and reporting tasks. Te power source ofen consists
of a battery with limited energy. In an unattainable environ-
ment, it could not be possible or inconvenient to recharge the
battery. Terefore, the sensor network should have a lifetime
long enough to fulfll the application requirements. A single
node failure, due to limited energy, could afect WMSNs
lifetime and/or overall utilization.
To prolong network lifetime in environmental moni-
toring and process control applications, the bulk amount
of monitored multimedia data needs to be efciently com-
pressed before transmission. But, multimedia compression
algorithms, image compression, are constrained by pro-
cessing and communication efciency of sensor nodes in
WMSNs.
In this paper we consider energy and resources efcient
distributed image compression in environmental monitor-
ing and process control applications. Our scheme uses
distributed lapped biorthogonal transform- (LBT-) based
compression scheme to compress and transmit the data to
base station. Our scheme has the following key contributions.
(a) We prune out low-energy nodes through energy-level
driven clustering algorithm and classify the potential
nodes for processing LBT-based image compression.
As a result, both the network lifetime and network
utilization efciency are improved signifcantly.
Hindawi Publishing Corporation
International Journal of Distributed Sensor Networks
Volume 2014, Article ID 148595, 9 pages
http://dx.doi.org/10.1155/2014/148595