scope:

Organization of the document

This International Standard specifies a metadata system for describing multimedia content. This document specifies the Multimedia Description Schemes (MDS) description tools (Description Schemes, Descriptors, and datatypes) that comprise ISO/IEC 15938-5. The following set of subclauses are provided for each MDS description tool, where optional subclauses are indicated as (optional):

• Syntax: specifies the normative syntax of the description tool using Description Definition Language (DDL) (see ISO/IEC 15938-2).

• Binary syntax (optional): specifies the normative binary representation for the description tool, where relevant. If a binary syntax is not specified, then the binary coding method of ISO/IEC 15938-1 shall apply for the description tool.

• Semantic: specifies the normative semantics of the description tool and each of its components (attributes and elements).

• Informative examples (optional): provides informative examples that illustrate the use or instantiation of the description tool in creating descriptions.

Overview of Multimedia Description Schemes

The basic elements, which are shown at the bottom level in Figure 1, form the building blocks for the higher-level description tools. The following basic elements are defined: schema tools (the root element, top-level types, description metadata, and packages), basic datatypes (integers, reals, vectors, matrices), linking and media localization tools (spatial and temporal localization), basic description tools (language, text, classification schemes). The basic elements are specified in the following clauses: clause 4 (Schema tools), clause 5 (Basic datatypes), clause 6 (Linking, identification and localization tools), and clause 7 (Basic description tools). Table 1 summarizes the basic elements.

The content description tools, which are shown at the middle level in Figure 1, describe the features of the multimedia content and the immutable metadata related to the multimedia content. The following description tools for content description are defined: structure description tools (spatio-temporal segments of multimedia content) and semantic description tools (objects, events). The following description tools for content metadata are defined: media description (storage format, encoding), creation & production (title, creator, classification), and usage (access rights, publication). The content description and metadata tools are related in the sense that the content description tools use the content metadata tools. For example, a description of creation and production or media information can be attached to an individual video or video segment in order to describe the structure and creation and production of the multimedia content. Table 2 summarizes tools for describing content and related metadata.

The tools for navigation and access, which are shown at the middle level in Figure 1, describe the browsing, summarization, and access of content. These tools are specified in clause 13 (Navigation and access tools). The tools for content organization tools, shown at the top level in Figure 1, describe collections and models of multimedia content. These tools are specified in clause 14 (Content organization tools). The tools for user interaction, shown on the right in Figure 1, describe user preferences pertaining to consumption of multimedia and usage history. These tools are specified in clause 15 (User interaction tools). Table 3 summarizes tools for describing content organization, navigation and access, and user interaction.

Finally, classification schemes, which organize terms that are used by the description tools, are specified in Annex B (Classification Schemes).