A team of researchers has developed an effective strategy to detect spy cameras using a smartphone. Dubbed LAPD, this new method addresses the limitations of most other solutions existing today.
Using Smartphone To Detect Hidden Cameras via LAPD Technique
Researchers from the National University of Singapore, Singapore, and Yonsei Univerity, South Korea, have revealed how a smartphone can spot hidden spy cameras. All it takes is downloading an app on the phone, which uses its time-of-flight (ToF) sensors to spot the cameras.
The researchers explained that most contemporary smartphones encase time-of-flight sensors to measure depth virtually. These sensors aid augmented reality-based experiences such as gaming.
So, the researchers proposed using this sensor to detect the reflections from camera surfaces hidden in various objects. They have termed this methodology “LAPD” (LaserAssisted Photography Detection). Users can download the LAPD app on their phones to detect cameras in suspected regions. Then, a simple scan of the suspected objects will let the users know about the presence of hidden cameras.
Most hidden cameras today exhibit small, difficult-to-detect form factors, especially those that just rely on a memory card for video storage with no live streaming. Hence, researchers believe that LAPD can prove helpful as it addresses the limitations of previous methodologies that typically rely on the traffic generated from the cameras.
In their study, the researchers tested the app in real-world setups involving 379 participants. They achieved better camera detection via LAPD at the rate of 88.9% compared to the 46% detection rate via the naked eye.
How LAPD works
Describing how it works, the researchers stated,
Specifically, the hidden camera embedded in the object reflects the incoming laser pulses at a higher intensity than its surroundings due to an effect called lens-sensor retro-reflection. This occurs when almost all light energy impacting an object is reflected directly back to the source. These unexpectedly high-intensity reflections from hidden cameras cause certain regions of the ToF sensor to be “saturated” and appear as black pixels. LAPD processes these saturated areas to automatically identify the hidden camera and its location and displays it on the user’s smartphone screen.
The following video demonstrates LAPD in action.
While LAPD can effectively detect hidden cameras, the method also has some limitations. The most significant limitation is the reliance on ToF sensors. So, any smartphones lacking this particular sensor will not be able to use LAPD.
Similarly, limitations also exist in the LAPD result rendering that depends on the accuracy of the underlying 3D localization system.
Interested users can read more about this study in the research paper the team has shared.