RtAudio is a set of C++ classes that provide a common API
(Application Programming Interface) for realtime audio input
and output across Linux, Macintosh OS-X and Windows operating
systems.
RtAudio significantly simplifies the process of interacting
with computer audio hardware.

It was designed with the following objectives:

- object-oriented C++ design
- simple, common API across all supported platforms
- only one source and one header file for easy inclusion in
  programming projects
- allow simultaneous multi-api support
- support dynamic connection of devices
- provide extensive audio device parameter control
- allow audio device capability probing
- automatic internal conversion for data format, channel number
  compensation, (de)interleaving, and byte-swapping

RtAudio incorporates the concept of audio streams, which represent
audio output (playback) and input (recording).
Available audio devices and their capabilities can be enumerated
and then specified when opening a stream.
Where applicable, multiple API support can be compiled and a
particular API specified when creating an RtAudio instance.