Image Processing Capabilities of ARM-based Micro-controllers for Visual Sensor Networks

Last decade witnessed the rapid development of Wireless Sensor Networks (WSNs). More recently, the availability of inexpensive hardware such as CMOS cameras and microphones that are able to ubiquitously capture multimedia content from the environment has fostered the development of Wireless Multimedia Sensor Networks (WMSNs) [1]. Nodes in such networks require significant amount of processing power to interpret the collected sensor data. Most of the currently available wireless multimedia sensor nodes are equipped with ARM7 core micro-controllers [2]. On the other hand, ARM9 core is a viable alternative, which delivers deterministic high performance and flexibility for demanding and cost-sensitive embedded applications. Thus, we evaluated the performance of the ARM7 core against the ARM9 core in terms of processing power and energy consumption. Our test results showed that architectural improvements of the ARM9 core alone resulted in a 30% speed-up in execution time, where the ARM9 core in general performed 9 to 11 times faster than the ARM7 core.