Structured Audio Orchestra Language

Last updated
Structured Audio Orchestra Language
Paradigm Imperative programming
Family MUSIC-N
First appeared1999
Filename extensions .saol
Website www.saol.net

Structured Audio Orchestra Language (SAOL) is an imperative, MUSIC-N programming language designed for describing virtual instruments, processing digital audio, and applying sound effects. It was published as subpart 5 of MPEG-4 Part 3 (ISO/IEC 14496-3:1999) in 1999. [1] [2] [3] [4]

In computer science, imperative programming is a programming paradigm that uses statements that change a program's state. In much the same way that the imperative mood in natural languages expresses commands, an imperative program consists of commands for the computer to perform. Imperative programming focuses on describing how a program operates.

MUSIC-N refers to a family of computer music programs and programming languages descended from or influenced by MUSIC, a program written by Max Mathews in 1957 at Bell Labs. MUSIC was the first computer program for generating digital audio waveforms through direct synthesis. It was one of the first programs for making music on a digital computer, and was certainly the first program to gain wide acceptance in the music research community as viable for that task. The world's first computer-controlled music was generated in Australia by programmer Geoff Hill on the CSIRAC computer which was designed and built by Trevor Pearcey and Maston Beard. However, CSIRAC produced sound by sending raw pulses to the speaker, it did not produce standard digital audio with PCM samples, like the MUSIC-series of programs.

Programming language Language designed to communicate instructions to a machine

A programming language is a formal language, which comprises a set of instructions that produce various kinds of output. Programming languages are used in computer programming to implement algorithms.

Contents

As part of the MPEG-4 international standard, SAOL is one of the key components of the MPEG-4 Structured Audio toolset, along with:

MPEG-4 is a method of defining compression of audio and visual (AV) digital data. It was introduced in late 1998 and designated a standard for a group of audio and video coding formats and related technology agreed upon by the ISO/IEC Moving Picture Experts Group (MPEG) under the formal standard ISO/IEC 14496 – Coding of audio-visual objects. Uses of MPEG-4 include compression of AV data for web and CD distribution, voice and broadcast television applications. The MPEG-4 standard was developed by a group led by Touradj Ebrahimi and Fernando Pereira.

International standards are technical standards developed by international organizations, such as Codex Alimentarius in food, the World Health Organization Guidelines in health, or ITU Recommendations in ICT and being publicly funded, are freely available for consideration and use worldwide.

MPEG-4 Structured Audio is an ISO/IEC standard for describing sound. It was published as subpart 5 of MPEG-4 Part 3 in 1999.

In computing, scheduling is the method by which work is assigned to resources that complete the work. The work may be virtual computation elements such as threads, processes or data flows, which are in turn scheduled onto hardware resources such as processors, network links or expansion cards.

See also

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References

  1. ISO (1999). "ISO/IEC 14496-3:1999 - Information technology -- Coding of audio-visual objects -- Part 3: Audio". ISO. Retrieved 2009-10-06.
  2. ISO/IEC JTC 1/SC 29/WG 11 (1998-05-15), ISO/IEC FCD 14496-3 Subpart 5 - Information Technology - Coding of Audiovisual Objects – Low Bitrate Coding of Multimedia Objects, Part 3: Audio, Subpart 5: Structured Audio, Final Committee Draft, N2203SA (PDF), retrieved 2009-10-10
  3. D. Thom, H. Purnhagen, and the MPEG Audio Subgroup (October 1998). "MPEG Audio FAQ Version 9 - MPEG-4". chiariglione.org. Archived from the original on 2009-09-26. Retrieved 2009-10-06.CS1 maint: multiple names: authors list (link)
  4. Heiko Purnhagen (2001-06-01). "The MPEG-4 Audio Standard: Overview and Applications". Heiko Purnhagen. Retrieved 2009-10-07.[ dead link ]