A novel approach for audible acoustic quick response codes

Compared to image-based quick response (QR) codes, acoustic QR codes have some advantages. However, an acoustic QR scanner cannot recognize an acoustic QR code at a distance of more than two meters from an acoustic QR announcer. To this end, we propose a new sort of acoustic QR code, called an audible acoustic QR code (AAQRC), which employs humanly audible sound to carry users' information directly. First, a user's string of characters is translated into a string of pitches. Then, the related algorithms convert the string of pitches into a playable audio file. As a result, an AAQRC is generated, consisting of the audio itself. AAQRC recognition is the opposite process of AAQRC generation. Compared with the existing approach for acoustic QR codes, the new method can recognize acoustic QR codes at a longer distance, even if there are obstacles between the AAQRC announcer and AAQRC scanner.