CAJ | 학술논문

针对无线传感器网络能量、存储、处理能力严重受限的特点,基于"在网计算"的思想,结合JPEG2000算法流程以及无线传感器网络的网络拓扑结构特点,提出一种基于邻居簇的JPEG2000多节点协同图像压缩方法.首先,将相机节点采集的图像分片,并根据图像的梯度幅度值进行压缩比特率的自适应优化分配.然后,将压缩任务转移到多个邻居簇内,以最小化网络总能耗为目标,由多节点协作共同完成图像压缩和传输.仿真结果表明,该方法不仅使无线传感器网络中实现大尺寸图像的JPEG2000编码成为可能,且相机节点能耗仅为压缩图像后传输至基站方案的3.4%,极大地平衡了网络节点能耗,使网络生命周期提高了7倍以上.
침대무선전감기망락능량、존저、처리능력엄중수한적특점,기우"재망계산"적사상,결합JPEG2000산법류정이급무선전감기망락적망락탁복결구특점,제출일충기우린거족적JPEG2000다절점협동도상압축방법.수선,장상궤절점채집적도상분편,병근거도상적제도폭도치진행압축비특솔적자괄응우화분배.연후,장압축임무전이도다개린거족내,이최소화망락총능모위목표,유다절점협작공동완성도상압축화전수.방진결과표명,해방법불부사무선전감기망락중실현대척촌도상적JPEG2000편마성위가능,차상궤절점능모부위압축도상후전수지기참방안적3.4%,겁대지평형료망락절점능모,사망락생명주기제고료7배이상.
In combination of the characteristic of JPEG2000 and the network architecture of Wireless Sensor Networks (WSNs), a multi-node cooperative JPEG2000 image compression method based on neighbor clusters is proposed by using the concept of in network processing to improve their energy,meomory and computional power. Firstly, the images captured by the camera node are partitioned into tiles and the adaptive bit rate is allocated by a optimum method based on gradient magnitudes. Then the tiles are sent to the neighbor clusters and compressed by multiple nodes cooperatively to minimize the total energy consumption of the network. Simulation results show that the proposed image compression method not only realizes the JPEG2000 compression of big size images in the WSNs, but also balances the energy load among all nodes. Compared with the compressing image before sending it to the base station, the proposed method has decreased the energy consumption of the camera node to 3.4%. These results show that the lifetime period of the network has improved by 7 times.