Scalable Visual Codes for Embedding Digital Data in the Physical World

Hermans, Frederik and McNamara, Liam and Voigt, Thiemo (2015) Scalable Visual Codes for Embedding Digital Data in the Physical World. In: Embedded Networked Sensor Systems (SenSys), 2015, Seoul, South Korea.

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Visual codes, such as QR codes, offer a low-cost alternative to RF technology when digital data needs to be embedded in objects in the physical world. However, in order to sup- port receivers with a poor visual channel, e.g. low-resolution cameras, most visual codes are designed for low data capacity and short reading distances. We present our work-in-progress on Focus, a visual code that avoids earlier work’s explicit trade-off between code capacity and channel quality. Rather than encoding the pay- load directly into individual pixels, Focus encodes the pay- load over a range of spatial frequencies. As a result, even a receiver with a very poor channel (e.g., with low-resolution camera or motion blur) can still partly decode a Focus code, because the code’s low-frequency components are robust to common channel impairments. A receiver with a good channel can decode all data from the same code. In our demo, we will present a prototype of Focus for smartphones and showcase how it deals with common impairments of the visual channel.

Item Type:Conference or Workshop Item (Other)
ID Code:5937
Deposited By:Liam McNamara
Deposited On:15 Jan 2016 10:22
Last Modified:10 Aug 2016 11:17

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