The original aptX algorithm was developed in the 1980s by Dr. Stephen Smyth as part of his Ph.D. research at Queen’s University Belfast School of Electronics, Electrical Engineering and Computer Science;[3] its design is based on time domain ADPCM principles without psychoacoustic auditory masking techniques.
aptX audio coding was first introduced to the commercial market as a semiconductor product, a custom programmed DSP integrated circuit with part name APTX100ED, which was initially adopted by broadcast automation equipment manufacturers who required a means to store CD-quality audio on a computer hard disk drive for automatic playout during a radio show, for example, hence replacing the task of the disc jockey.
Since its commercial introduction in the early 1990s, the range of aptX algorithms for real-time audio data compression has continued to expand with intellectual property becoming available in the form of software, firmware and programmable hardware for professional audio, television and radio broadcast, and consumer electronics, especially applications in wireless audio, low latency wireless audio for gaming and video, and audio over IP.[4] In addition, the aptX codec can be used instead of SBC, the sub-band coding scheme for lossy stereo/mono audio streaming mandated by the Bluetooth SIG for the Advanced Audio Distribution Profile (A2DP) of Bluetooth, the short-range wireless personal-area networkstandard. aptX is supported in high-performance Bluetooth peripherals.[5][6]
Today, both standard aptX and Enhanced aptX (E-aptX) are used in both ISDN and IP audio codec hardware from numerous broadcast equipment makers, including APT WorldCast Systems,[7] Tieline Technology, AVT, Harris Corporation, BW Broadcast, Digigram, MAYAH, Prodys, and Qbit. An addition to the aptX family in the form of aptX Live, offering up to 8:1 compression, was introduced in 2007;[8] and aptX-HD, a lossy, but scalable, adaptive, “near-lossless” quality audio codec was announced in April, 2009.[9]
aptX was previously named apt-X until acquired by CSR plc in 2010.[10] CSR was subsequently acquired by Qualcomm in August 2015.[11]