I N N O V A T I O N S F O R E M B E D D E D D E S I G N S Using Smartphones and Tablets in Embedded Applications This white paper discusses the issues with transferring video and other high bandwidth data to a smartphone, iphone, ipad or other tablet device in embedded applications. An example application using a specialty USB camera and an embedded wireless network processor board is shown. Smartphones and tablets are proliferating through the commercial markets with more shipments today than PCs. Just as the PC did in the 1980 s and early 1990 s, smartphones and tablets are finding increased use in embedded applications such as medical and industrial automation due to their low price and wide availability. Applications based on PC technologies will naturally be ported to these new technologies to remain competitive. Smartphone and Tablet Shipments vs. PCs The processing power of these devices now rivals PCs, making them well suited for operator input, control, and data display. Their portability also allows for greater worker mobility in applications with dynamic environments. Their cloud connectivity capabilities through 3G and 4G networks make them appealing for applications needing to share information anytime, anywhere. The advanced display technologies used on these devices, such as the retina display on the latest ipad from Apple, is stunning in resolution and color depth, which adds to their appeal. There are challenges in using these devices for embedded applications. One of the biggest issues is that these devices do not typically include a wide variety of expansion ports for connecting peripherals and sensors. The majority of current generation smartphones and tablets
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Page 4 of 5 GW2382 Network Processor OpenWRT Linux USB Host USB UVC Camera GStreamer Multimedia Framework Optional JPEG Compression HTTP Web Server 802.11b Wireless ipad Software - ios 802.11b Wireless Web Browser Example Application Software Diagram The standard board support package (BSP) supplied with the GW2382 contained drivers for the USB host port and for the wireless radio. An additional UVC camera driver was then required for communicating with the camera. From here, a mechanism was needed to take the video stream and optionally compress and send to the HTTP web server. It was desirable to support several different camera types with different resolutions along with cameras with built-in JPEG compression and additionally raw video cameras. The open source GStreamer multimedia framework (www.gstreamer.net) was used to create a simple application for this operation. GStreamer allowed for this flexibility along with providing easily configured plug-in codecs for implementing the JPEG compression. On the ipad or Android device side, in the simplest form, the standard web browser could be used to view the video stream and select the different resolutions, frame rate, and compression. For a more polished user interface, a dedicated ipad application was created by Perceptive Development (www.perceptivedevelopment.com). This application added additional functionality such as user configuration settings, capturing stills of the live video, picture zoom, and managing software upgrades for the GW2382 embedded network processor board. A picture showing the complete solution is shown below.
Page 5 of 5 Example Application Final Configuration This application provides just one example of how an embedded network processor board can be used to provide a simple connection between a sensor and a smartphone or tablet. Using a network processor board allows both the sensor and the software to be decoupled from the smartphone or tablet, greatly simplifying the design. This same basic architecture can be expanded to support a wide variety of applications and sensors. Definition: Network Processor Board A motherboard designed specifically for embedded wireless network applications. Author Biography Ron Eisworth is the VP of Sales and Marketing at Gateworks Corporation and has worked in embedded design for over 25 years. He holds a BS degree in Electronic Engineering from Cal Poly San Luis Obispo, California and a MS in Electrical Engineering from the University of California at Santa Barbara. About Gateworks Corporation Gateworks Corporation is the leading supplier of powerful ARM-based board-level solutions for embedded wired and wireless network systems. Gateworks products are designed for demanding environments and operate over the full industrial temperature range. The company is headquartered in San Luis Obispo, California and manufactures 100% of its products in a highly efficient, automated SMT assembly facility in San Luis Obispo, California. For more information, see the company website at www.gateworks.com or email sales@gateworks.com. About Perceptive Development Perceptive Development has been developing ios and Android applications and attached peripherals since 2009. Contact Perceptive Development at www.perceptivedevelopment.com or phone (310)-953-3640 for more information on how they can help you develop your embedded mobile application.