Media Contract Formalization Using a Standardized Contract Expression Language

Contract expression languages (CELs) let users represent business contracts in a digital and structured form. Examples include the Content Reference Forum format, the OASIS eContracts standard, and a proposed extension for MPEG-21 Part 5. These formats have influenced the MPEG-21 CEL design, which has been recently specified by modeling the most relevant clauses in audiovisual contracts. As the authors describe, the MPEG-21 CEL defines a language for representing media contracts as XML. It's structured in two schemas: a core defining a contract's structural elements, and an extension with vocabulary for specific applications.