An inexpensive wireless smart camera system for IoT applications based on an ARM Cortex-M7 microcontroller

Abstract

This paper presents a new proposal of a low-cost and low-power wireless smart camera device, designed to be used as an inexpensive smart image acquisition edge node for Internet of Things (IoT). Taking the advantages of the ARM CortexM7 microcontrollers, a high-performance STM32F7 microcontroller is used as a main digital signal processor (DSP) to acquire and transfer images at full rate, keeping the core idle to do real-time image processing. In order to design a very compact, low-cost and low-power wireless image sensor node, the DSP is supported by an embedded 1.3 Mega Pixel CMOS camera sensor and a low consumption 2.4GHz Wi-Fi module. This setup allows a custom build-in image processing algorithm for specific IoT sensing applications or a simply setup as low-cost streaming Motion JPEG (MJPEG) wireless camera node. In this work, both configurations have been tested and analyzed. Results show that the device can acquire and process images simultaneously at a full rate (30 fps) and the MJPEG transmission reaches 7.23 fps with a QVGA resolution.