Out of Sight!

QR codes, short for quick response codes, are two-dimensional barcodes that have become popular due to their ability to store and quickly retrieve information. Developed in the 1990s by the Japanese company Denso Wave, QR codes are now widely used in a variety of fields, from marketing and advertising to logistics and authentication. These codes are made up of black squares arranged on a white background, and they can store more data than traditional barcodes.

These codes function by encoding information within the arrangement of the black and white squares. The data can include text, URLs, contact information, or even more complex information like product details or encrypted data. To decode a QR code, a device equipped with a camera and a QR code reader app captures an image of the code. The app processes the image, extracts the encoded information, and presents it to the user. This straightforward process allows for rapid access to data by simply scanning the code with a compatible device.

Generating a QR code and applying it to an object is incredibly simple. This adds to the popularity and widespread use of the technology, however, it also makes it prone to misuse. Cybercriminals can tamper with QR codes to direct users to malicious websites or to steal sensitive data. This can be done by overlaying a QR code on top of a legitimate one, effectively redirecting users to a fraudulent site that may capture their personal information or distribute malware. Unfortunately for a user, it can be virtually impossible to detect if a QR code has been tampered with.

Malicious hackers may soon have a much harder time pulling off QR code-related scams thanks to the work of a group of researchers at MIT CSAIL. They have created an invisible tagging system that can encode data much like a QR code, but is directly embedded within objects. The new tags, called BrightMarkers, may not completely eliminate the possibility of tampering, but they certainly make it much harder to do so, requiring much more sophisticated attacks than slapping a sticker on top of an existing tag.

To embed a BrightMarker in an object, a user first downloads MIT’s plugin for 3D modeling programs, such as Blender. Designs are created as usual, then the plugin assists in positioning the BrightMarker tag within the object. An STL file can then be exported for use with a 3D printer. The marker itself is printed using a fluorescent filament.

Once a BrightMarker has been embedded within an object, it will be invisible to the naked eye. However, with the help of an infrared camera, the markers are visible and high-resolution features can be deciphered. At that point, the contents of the marker can be decoded much like a normal QR code — whether a traditional or infrared camera captured the image is of little consequence.

This new technology can replace the ubiquitous QR codes that, for example, lead us to a website listing a restaurant’s menu. But they can also enhance more sophisticated applications involving motion tracking, virtual reality, and object detection.

In one demonstration, the team showed how a BrightMarker embedded in a toy lightsaber could be used to track it in a virtual reality environment. They believe that embedding the tracking markers directly into objects could result in a more immersive virtual experience.

In another experiment, it was shown how wearable devices with BrightMarker tags could be used to track the movement of arms and legs with precision. Such devices could be as simple and unobtrusive as bracelets, and the algorithms required to perform the tracking could be less computationally intensive than those that are typically used for this purpose.

The researchers’ ultimate goal is to facilitate effortless interactions between the physical and digital worlds. To get there, they are currently working to solve a few issues around occlusion of the markers that hinder tracking systems, and they are also working out a plan to allow for mass production of BrightMarkers.