Delivery of QR codes to cellular phones through data embedding in audio

摘要

We describe a system that delivers a website address to a cellular phone by encoding inaudible binary data within an analogue audio signal, to be received and decoded by the cellular phone. This is an alternative method to encoding web site address in QR code label and scanning it by the cellular phone camera. Data embedding in the audio signal is done by modifying the phase of its Modulated Complex Lapped Transform (MCLT) coefficients, and transforming it back to the time domain while the perceived quality of the embedded audio is kept the same as that of the origin. In this work a whole system which embeds data in an audio signal and transmits it over an acoustic channel was built and tested both by simulation and in reality. Data transmission rate is sufficient to deliver the same amount of information contained in a QR code label in a shorter time than it takes to aim a camera, scan, and decode the data. Additionally, with data embedding in audio several users may get service in parallel.