High-accuracy scheme based on a look-up table for motion detection in an optical camera communication system

Area of Science:

• Optical Camera Communication (OCC)
• Human-Computer Interaction
• Signal Processing

Background:

• Optical Camera Communication (OCC) systems offer a wireless communication channel using light emitters and cameras.
• Accurate motion detection (MD) is crucial for intuitive user interfaces and data input in OCC systems.
• Existing MD methods can be complex or lack accuracy in real-world scenarios.

Purpose of the Study:

• To propose and experimentally demonstrate a high-accuracy motion detection (MD) scheme for an optical camera communication (OCC) system.
• To enable simultaneous data transmission and motion recognition using a mobile phone camera.
• To develop a robust MD scheme resilient to variations in motion and user input.

Main Methods:

• A look-up table (LUT) containing predefined motion patterns (lines, circles, numbers) was created.
• Data modulation using on-off keying (OOK) on an LED array at the transmitter.
• Motion capture via a mobile phone camera, string conversion, and matching against the LUT using Levenshtein distance (LD) and modified Jaccard coefficient (MJC).

Main Results:

• The proposed MD scheme achieved high accuracy (up to 98%) in recognizing four types of finger motions.
• Simultaneous data transmission was successfully demonstrated alongside motion recognition.
• A low bit error rate (BER) below 1e-6 was achieved at a distance of 80cm.

Conclusions:

• The developed LUT-based MD scheme provides a highly accurate and efficient solution for OCC systems.
• The system enables intuitive user interaction and reliable data transfer using common mobile devices.
• This approach advances the capabilities of camera-based communication and human-computer interaction.