With the advent of high-resolution recording and playback systems, a proportion of the ultrasonic frequency spectrum can potentially be utilized as a carrier for imperceptible data, which can be used to trigger events or to hold metadata in the form of, for example, an ISRC (International Standard Recording Code), a website URL or audio track liner notes. The Sonic Quick Response Code (SQRC) algorithm was previously proposed as a method for encoding inaudible acoustic metadata within a 96 kHz audio file in the 30-35 kHz range