Network Working Group                                         M. Nilsson
Request for Comments: 3003                                 November 2000
Category: Standards Track
        
Network Working Group                                         M. Nilsson
Request for Comments: 3003                                 November 2000
Category: Standards Track

The audio/mpeg Media Type

音频/mpeg媒体类型

Status of this Memo

本备忘录的状况

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.

本文件规定了互联网社区的互联网标准跟踪协议，并要求进行讨论和提出改进建议。有关本协议的标准化状态和状态，请参考当前版本的“互联网官方协议标准”（STD 1）。本备忘录的分发不受限制。

Copyright Notice

版权公告

Copyright (C) The Internet Society (2000). All Rights Reserved.

版权所有（C）互联网协会（2000年）。版权所有。

Abstract

摘要

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.

MPEG-1和MPEG-2标准的音频层在internet上经常使用，但这些文件没有统一的多用途internet邮件扩展（MIME）类型。本文档的目的是定义媒体类型audio/mpeg以引用此类内容。

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 [RFC2119].

本文件中的关键词“必须”、“不得”、“要求”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照RFC 2119[RFC2119]中所述进行解释。

1. MPEG audio
1. mpeg声音

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.

在MPEG-1[MPEG-1]和MPEG-2[MPEG-2]标准中定义为第I层、第II层和第III层的音频压缩是压缩低质量损失的音频的常用方法。压缩音频被分成几个小数据帧，每个小数据帧包含一个帧头和压缩音频数据。

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.

mime类型音频/mpeg定义了一个基本字节流，其中包含符合[mpeg-1]和[mpeg-2]的mpeg帧，可能夹杂着非mpeg数据。非MPEG数据是没有MPEG同步或以其他方式无法无误解压缩的数据。

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

通常，MPEG音频元数据与MPEG流连接，例如，元数据格式ID3将128字节的数据块放在流的末尾，而ID3v2[ID3v2]将变量的数据块放在前面

size to the stream.

大小与流一致。

NOTE: MPEG audio was not designed as a file format but as a format for transmitting audio streams. As such, it does not have any well defined way of including meta data along with audio information. Some products embed meta data using zero amplitude frames or disguised as transmission errors. Others embed the MPEG data in WAV format.

注意：MPEG音频不是作为文件格式设计的，而是作为传输音频流的格式设计的。因此，它没有任何定义良好的方式将元数据与音频信息一起包含。有些产品使用零振幅帧嵌入元数据，或者伪装成传输错误。其他的则以WAV格式嵌入MPEG数据。

NOTE: The audio/MPS mime type is in use in addition to the audio/mpeg. The MPA [RFC 1890] sub-type refers to MPEG audio when it is segmented and send as a Realtime Transport Protocol (RTP) payload.

注意：除了音频/mpeg外，还使用音频/MPS mime类型。MPA[RFC 1890]子类型指的是MPEG音频，当它被分割并作为实时传输协议（RTP）有效负载发送时。

2. Registration Information
2. 注册信息 
   To: ietf-types@iana.org Subject: Registration of MIME media type
   audio/mpeg
        
   To: ietf-types@iana.org Subject: Registration of MIME media type
   audio/mpeg

MIME media type name: audio

MIME媒体类型名称：音频

MIME subtype name: mpeg

MIME子类型名称：mpeg

Required parameters: none

所需参数：无

Optional parameters: none

可选参数：无

Encoding considerations:

编码注意事项：

For use over internet it is assumed that lower layers take care of transmission errors, so audio/mpeg data MAY include MPEG frames generated without the optional cyclic redundancy checks (CRC) for improved audio quality.

为了在因特网上使用，假设较低层负责传输错误，因此音频/mpeg数据可以包括在没有用于改进音频质量的可选循环冗余校验（CRC）的情况下生成的mpeg帧。

The MPEG audio data is binary data, and must be encoded for non-binary transport; the Base64 encoding is suitable for Email. Note that the MPEG audio data does not compress easily using lossless compression.

MPEG音频数据是二进制数据，必须进行编码以进行非二进制传输；Base64编码适用于电子邮件。请注意，MPEG音频数据不容易使用无损压缩进行压缩。

Security considerations:

安全考虑：

MPEG is a tagged data format, and some tags are available for private use. As such, arbitrary material could potentially be transferred in the MPEG stream, including executable content. Tagged data containing executable content SHOULD never be sent and MUST not be executed if it is received.

MPEG是一种带标签的数据格式，有些标签可供私人使用。因此，可以在MPEG流中传输任意材料，包括可执行内容。不应发送包含可执行内容的标记数据，如果接收到该数据，则不得执行该数据。

NOTE

笔记

The requirement that such content not be executed on receipt is especially important since situations exist where content will be generated independently and therefore could contain executable content that the sender is unaware of.

由于存在内容将独立生成的情况，因此可能包含发送方不知道的可执行内容，因此在接收时不执行此类内容的要求尤为重要。

Audio/mpeg objects are not signed or encrypted internally. External security mechanisms must be employed to ensure content confidentiality

音频/mpeg对象未在内部签名或加密。必须使用外部安全机制来确保内容的机密性

Interoperability considerations:

互操作性注意事项：

MPEG audio has proven to be widely interoperable across computer platforms.

MPEG音频已被证明可以跨计算机平台进行广泛的互操作。

Published specification: see [MPEG-1] and [MPEG-2]

已发布规范：参见[MPEG-1]和[MPEG-2]

Applications which use this media type:

使用此媒体类型的应用程序：

MPEG audio is device-, platform- and vendor-neutral and is supported by a wide range of encoders and decoders (players).

MPEG音频不受设备、平台和供应商的影响，并由多种编码器和解码器（播放器）支持。

Additional information:

其他信息： 

       Magic number(s): none
       File extension(s): .mp1, .mp2, .mp3
       Macintosh File Type Code(s): MPEG
       Object Identifier(s) or OID(s): none
        
       Magic number(s): none
       File extension(s): .mp1, .mp2, .mp3
       Macintosh File Type Code(s): MPEG
       Object Identifier(s) or OID(s): none

Person & email address to contact for further information:

联系人和电子邮件地址，以获取更多信息：

The author of this document.

本文件的作者。

Intended usage: COMMON

预期用途：普通

Author/Change controller: Martin Nilsson (see section 5)

作者/变更控制员：马丁·尼尔森（见第5节）

3. Security Considerations

3. 安全考虑

Security considerations are discussed in the security considerations clause of the MIME registration in section 2.

第2节MIME注册的安全注意事项条款讨论了安全注意事项。

4. References
4. 工具书类 
   [ID3v2]
     Martin Nilsson, "ID3 tag version 2.3.0".
     <url:http://www.id3.org/id3v2.3.0.txt>
        
   [ID3v2]
     Martin Nilsson, "ID3 tag version 2.3.0".
     <url:http://www.id3.org/id3v2.3.0.txt>
        
   [MPEG-1]
     ISO/IEC 11172-3:1993.
     Coding of moving pictures and associated audio for digital storage
     media at up to about 1,5 Mbit/s, Part 3: Audio.
     Technical committee / subcommittee: JTC 1 / SC 29
        
   [MPEG-1]
     ISO/IEC 11172-3:1993.
     Coding of moving pictures and associated audio for digital storage
     media at up to about 1,5 Mbit/s, Part 3: Audio.
     Technical committee / subcommittee: JTC 1 / SC 29

[MPEG-2] ISO/IEC 13818-3:1995 Generic coding of moving pictures and associated audio information, Part 3: Audio. Technical committee / subcommittee: JTC 1 / SC 29

[MPEG-2]ISO/IEC 13818-3:1995运动图像和相关音频信息的通用编码，第3部分：音频。技术委员会/小组委员会：JTC 1/SC 29

and

和

ISO/IEC DIS 13818-3 Generic coding of moving pictures and associated audio information, Part 3: Audio (Revision of ISO/IEC 13818-3:1995)

ISO/IEC DIS 13818-3运动图像和相关音频信息的通用编码，第3部分：音频（ISO/IEC 13818-3-1995修订版）

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.

[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。

5. Author's Address
5. 作者地址

Martin Nilsson Rydsvagen 246 C. 30 S-584 34 Linkoping Sweden

Martin Nilsson Rydsvagen 246 C.30 S-584 34 Linkoping瑞典 

   EMail: nilsson@id3.org
        
   EMail: nilsson@id3.org
6. Full Copyright Statement
6. 完整版权声明

Copyright (C) The Internet Society (2000). All Rights Reserved.

版权所有（C）互联网协会（2000年）。版权所有。

This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English.

本文件及其译本可复制并提供给他人，对其进行评论或解释或协助其实施的衍生作品可全部或部分编制、复制、出版和分发，不受任何限制，前提是上述版权声明和本段包含在所有此类副本和衍生作品中。但是，不得以任何方式修改本文件本身，例如删除版权通知或对互联网协会或其他互联网组织的引用，除非出于制定互联网标准的需要，在这种情况下，必须遵循互联网标准过程中定义的版权程序，或根据需要将其翻译成英语以外的其他语言。

The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns.

上述授予的有限许可是永久性的，互联网协会或其继承人或受让人不会撤销。

This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

本文件和其中包含的信息是按“原样”提供的，互联网协会和互联网工程任务组否认所有明示或暗示的保证，包括但不限于任何保证，即使用本文中的信息不会侵犯任何权利，或对适销性或特定用途适用性的任何默示保证。

Acknowledgement

确认

Funding for the RFC Editor function is currently provided by the Internet Society.

RFC编辑功能的资金目前由互联网协会提供。