Memory Efficient Image Compression Scheme for Multimedia Sensor Networks

Image transmission in multimedia sensor network is a major challenge which raises issues related to its representation, storage and transmission. Image transmission over the network consume too much of energy and bandwidth. The computational and memory resources of wireless sensor nodes are typically very limited. These limitations prevent the application of modern signal processing techniques to preprocess the collected sensor data for energy and bandwidth efficient transmission over sensor networks. Image compression is one such technology that has been developed to reduce image size and used by Wireless Sensor Networks (WSN) applications. The original DCT transform algorithm and existing wavelet-based picture compression system is too complicated to be applied in the sensor node. In this paper, we describe a line-based DWT and Integer DCT based image compression algorithm particularly suited to the reduced storage and computational resources of a WSN node. The experimental result shows that the DCT transform is better than the DWT in terms of image quality but the DWT outperforms DCT in terms of memory space used.