Energy Efficient Data Processing in Visual Sensor Network

Identifying moving objects from a video sequence is a fundamental and critical task in many computervision applications. After the images are captured they must be processed and then sent to the server. In this paper we characterize the energy consumption of a visual sensor network testbed. Each node in the testbed consists of a "single-board computer", equipped with a network card and a webcam. We assess the energy consumption of activities representative of the target application (e.g., perimeter surveillance) using a benchmark that runs (individual and combinations of) "basic" tasks such as processing, image acquisition, and communication over the network. In our characterization, we consider the various hardware states that the system switches through as it executes these benchmarks, e.g., different radio modes (sleep, idle, transmission, reception), and webcam modes (off, on, and acquiring image) using Matlab Sensor Node and Lifetime simulator. We report the energy utilized by each frame during transmission at the server. Here we can analyze the energy consumed with processing and without processing of video frames.