本国际标准定义了多媒体内容描述接口，规定了一系列接口 从系统到应用程序级别，允许不同的系统交换有关多媒体内容的信息。信息技术 描述系统的体系结构、用于扩展和特定应用程序的语言，以及中的描述工具 音频和视频域，以及非特定于音频和视频域的工具。总的来说 包含上述所有组件的国际标准称为“MPEG-7”MPEG-7是 分为八个部分（定义见前言）。 MPEG-7标准的这一部分（第4部分:音频）规定了音频中与多媒体相关的描述工具 领域有关申请的更多详细信息，请参见下文。 MPEG-7标准的这一部分旨在与该标准的其他部分一起实施。 在里面 特别是，MPEG-7第4部分:音频假定了解第2部分:描述定义语言（DDL）的基本知识 描述符和描述方案的规范性语法定义。标准的这一部分也有 依赖于第5部分:多媒体描述方案中的条款，即许多基本 扩展DDL基本类型功能的描述方案。 MPEG-7是一种可扩展的标准。将标准扩展到提供的描述方案之外的方法 该标准的目的是在DDL中定义新的DSs，并使这些DSs与实例化的 描述。更多细节见第2部分。为避免与标准的其他部分重复功能， DDL是唯一提供的扩展设施。

This International Standard defines a Multimedia Content Description Interface, specifying a series of interfaces from system to application level to allow disparate systems to interchange information about multimedia content. It describes the architecture for systems, a language for extensions and specific applications, description tools in the audio and visual domains, as well as tools that are not specific to audio-visual domains. As a whole, this International Standard encompassing all of the aforementioned components is known as "MPEG-7." MPEG-7 is divided into eight parts (as defined in the Foreword). This part of the MPEG-7 Standard (Part 4: Audio) specifies description tools that pertain to multimedia in the audio domain. See below for further details of application. This part of the MPEG-7 Standard is intended to be implemented in conjunction with other parts of the standard. In particular, MPEG-7 Part 4: Audio assumes knowledge of Part 2: Description Definition Language (DDL) in its normative syntactic definitions of Descriptors and Description Schemes. This part of the standard also has dependencies upon clauses in Part 5: Multimedia Description Schemes, namely many of the fundamental Description Schemes that extend the basic type capabilities of the DDL. MPEG-7 is an extensible standard. The method to extend the standard beyond the Description Schemes provided in the standard is to define new ones in the DDL, and to make those DSs available with the instantiated descriptions. Further details are available in Part 2. To avoid duplicate functionality with other parts of the standard, the DDL is the only extension facility provided.