An audio stream redirector for the Ethernet Speaker

Abstract

The authors have developed the “Ethernet Speaker” (ES), a network‐enabled single board computer embedded into a conventional audio speaker. Audio streams are transmitted in the local area network using multicast packets, and the ES can select any one of them and play it back. A key requirement for the ES is that it must be capable of playing any type of audio stream, independent of the streaming protocol, or the encoding used. The authors achieved this by providing a streaming audio server built using the kernel‐based audio stream redirector (ASR) in the OpenBSD kernel. The ASR accepts input from any of the existing audio file players, or streaming audio clients. Since all audio applications have to be able to use the system audio driver, this system can accommodate any protocol or file format, provided that there exists some compatible player running under OpenBSD. This paper discusses the design and implementation of the server as an ASR, the streaming protocol developed for this application, and the implementation of the client.

Citation

Mandrekar, I., Prevelakis, V. and Turner, D.M. (2004), "An audio stream redirector for the Ethernet Speaker", Campus-Wide Information Systems, Vol. 21 No. 5, pp. 211-216. https://doi.org/10.1108/10650740410567572