In this paper, we propose two image transmission schemes driven by energy efficiency considerations in order to be suitable for wireless sensor networks. The first one is an open-loop image transmission scheme while the second one is closed-loop. Both schemes are based on wavelet image transform and semi-reliable transmission to achieve energy conservation. Wavelet image transform provides data decomposition in multiple levels of resolution, so the image can be divided into packets with different priorities. Semi-reliable transmission enables priority-based packet discarding by intermediate nodes according to their battery's state-of-charge. Such an image transmission approach provides a graceful trade-off between the image quality played out and the sensor nodes' lifetime. An analytical study in terms of dissipated energy is performed to compare our two schemes to a fully reliable image transmission scheme. Since image processing is computationally intensive and operates on a large data set, the cost of the wavelet image transform is considered in the energy consumption analysis. Results show up to 70% and 90% reductions in energy consumption with the open-loop and closed-loop schemes respectively compared to a non energy-aware one, with a guarantee for the image quality to be lower-bounded.
In another effort REF , the authors use an image transform and semi-reliable transmission to achieve energy conservation in order to provide a graceful tradeoff between the image quality and the sensor nodes' lifetime.
Energy-efficient image transmission in sensor networks
IJSNet
IJSNet
Computer Science