In the year 1999 MPEG understood that its technologies were having a disruptive impact on the media business. MPEG thought that the industry should not fend of a new threat with old repressive tools. The industry should convert the threat into an opportunity, but there were no standard tools to do that.

MPEG-21 is the standard resulting from the effort by MPEG to create a framework that would facilitate electronic commerce of digital media. It is a suite of specifications for end-to-end multimedia creation, delivery and consumption that can be used to enable open media markets.

This is represented in Figure 55. The basic MPEG-21 element is the Digital Item, a structured digital object with a standard representation, identification and metadata, around which a set of specifications were developed. MPEG-21 also includes specifications of Rights and Contracts and basic technologies such as the file format.

Figure  55 – Components of the MPEG-21 standard

An overview of the entire MPEG-21 standard, whose official title of MPEG-21 is Multimedia Framework, is available here. Some of the 21 MPEG-21 parts are briefly described below:

1. Part 2 – Digital Item Declaration specifies Digital Item (link)
2. Part 3 – Digital Item Identification specifies identification methods for Digital Items and their components (link)
3. Part 4 – Intellectual Property Management and Protection (IPMP) Components specifies how to include management and protection information and protected parts in a Digital Item (link)
4. Part 5 – Rights Expression Language specifies a language to express rights (link)
5. Part 6 – Rights Data Dictionary specifies a dictionary of rights-related data (link)
6. Part 7 – Digital Item Adaptation specifies description tools to enable optimised adaptation of multimedia content (link)
7. Part 15 – Event Reporting specifies a format to report events (links)
8. Part 17 – Fragment Identification of MPEG Resources specifies a syntax for URI Fragment Identifiers (link)
9. Part 19 – Media Value Chain Ontology specifies an ontology for Media Value Chains (link)
10. Part 20 – Contract Expression Language specifies a language to express digital contracts (link)
11. Part 21 – Media Contract Ontology specifies an ontology for media-related digital contracts (link).