RFC 3003 (rfc3003) - Page 1 of 5
The audio/mpeg Media Type
Alternative Format: Original Text Document
Network Working Group M. Nilsson
Request for Comments: 3003 November 2000
Category: Standards Track
The audio/mpeg Media Type
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2000). All Rights Reserved.
Abstract
The audio layers of the MPEG-1 and MPEG-2 standards are in frequent
use on the internet, but there is no uniform Multipurpose Internet
Mail Extension (MIME) type for these files. The intention of this
document is to define the media type audio/mpeg to refer to this kind
of contents.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC 2119].
1. MPEG audio
The audio compression defined as layer I, layer II and layer III in
the MPEG-1 [MPEG-1] and MPEG-2 [MPEG-2] standards is a popular method
of compressing audio with a low quality loss. The compressed audio
is split into several small data frames, each containing a frame
header and compressed audio data.
The mime type audio/mpeg defines a elementary byte stream containing
MPEG frames according to [MPEG-1] and [MPEG-2], possibly interspersed
with non MPEG data. Non MPEG data is data without MPEG
synchronization or in other ways not possible to decompress without
error.
Typically MPEG audio meta data is concatenated with the MPEG stream,
e.g., the meta data format ID3 puts a 128 byte data block in the end
of the stream while ID3v2 [ID3V2] prepends a data block of variable
Nilsson Standards Track