Overview - ISO/IEC 13522-8:2001 (XML notation for ISO/IEC 13522-5)
ISO/IEC 13522-8:2001 defines an XML 1.0 notation for encoding MHEG-5 objects (the multimedia and hypermedia application model defined in ISO/IEC 13522-5:1997). This part provides a third, functionally equivalent representation to the existing ASN.1 and EBNF/textual notations by expressing MHEG-5 semantics unambiguously in a Document Type Definition (DTD). Annex A contains the normative XML DTD; Annex B gives XML examples and Annex C addresses DTD validation.
Key topics and technical requirements
- XML-based representation: Specifies a DTD for MHEG-5 objects so applications and engines can consume MHEG-5 descriptions in XML 1.0 (W3C).
- DTD as normative artifact: The DTD in Annex A is the unambiguous specification used to validate any MHEG-5 application written in XML.
- Functional equivalence: This XML notation is explicitly intended to be functionally equivalent to the notations in ISO/IEC 13522-5:1997 (ASN.1 and textual/EBNF); it does not replace or invalidate clauses in Part 5.
- Object model elements: The DTD includes elements for core classes such as application, scene, link, program (residentprg, remoteprg), and many attributes and subelements (for example, onstartup/onclosedown actions, items lists, characterset, colours, fonts, input event registration and nextscenes).
- Conformance and validation: Implementations that publish or accept MHEG-5 XML must validate documents against the provided DTD. No new conformance requirements are imposed on ISO/IEC 13522-5 implementations beyond using the DTD to validate XML encodings.
Applications and who uses this standard
- Interactive TV and broadcasting: Broadcasters and middleware vendors use the XML notation to author, exchange, and validate interactive applications compatible with MHEG-5 engines.
- Software and engine developers: Developers of MHEG-5 runtimes, authoring tools, and content ingestion pipelines implement DTD-based XML parsing and validation.
- Web and intranet integration: Content authors and system integrators who bridge WWW technologies with broadcast systems benefit from an XML form that is familiar to HTML/XML toolchains.
- Test labs and standards bodies: Conformance testing and interoperability work benefit from a clear XML schema (DTD) for automated validation.
Related standards
- ISO/IEC 13522-5:1997 - Support for base-level interactive applications (normative reference)
- XML 1.0 (W3C Recommendation) - Underpins the notation and validation mechanisms
Keywords: ISO/IEC 13522-8:2001, MHEG-5, XML notation, DTD, multimedia and hypermedia, ISO/IEC 13522-5, interactive applications, validation, conformance, broadcasting.