ISO-13522-1-1997.pdf

INTERNATIONAL STANDARD ISO/IEC 13522-I First edition 1997-05-I 5 Information technology - Coding of multimedia and hypermedia information - Part 1: MHEG object representation - Base notation (ASN.l) Technologies de /information - Codage de /information multimkdia et hypermedia - Partie I: Repr these applications are highly interactive. - Sales and advertising: The association of attractive audiovisuals, showing the products to best advantage, with the stock control and ordering process is a natural commercial evolution. - Office information systems, engineering documentation: There is a long-standing need to be able to integrate drawings, images, audio and video into all types of office documentation. Integrated documents would also provide an attractive means of internal enterprise communication. - Culture: The computer processing of audiovisual information makes it possible to extend the audience for theatres, museums and cultural events. It also opens the possibility of new art forms. - Electronic publishing and electronic books: Much material that is currently published on paper could be enhanced by the integration of audiovisuals and by being available in a hypertext manner over a telecommunication network, for example, tourist guides and yellow pages, which could be a mixed sales and advertising application. - Public information: The use of audiovisual interfaces makes it possible for the public to use computer-based, real-time information systems, for example, a kiosk at which information is accessed through videotex or locally from CD. - Computer-supported multimedia co-operative work: There is a need to form effective teams of people who are geographically separated but have to share text, graphics, image, audio and other information, for example for remote maintenance, joint authorship or multimedia electronic mail. - Medical applications: There is a need for a timely retrieval of audiovisual information, including medical images, medical data and case history, in an integrated way from a remote site. This could be a mixed co- operative work application with different medical experts. - Interactive television applications: The emergence of digital television systems on terrestrial, satellite or cable networks, as well as the availability of new modulation and transmission techniques on the telephone network, creates favourable conditions for a new offer of interactive multimedia services based on the merging of television and telematics technologies, providing the users with interactive access to video documents. xli Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 04/02/2007 21:06:47 MDTNo reproduction or networking permitted without license from IHS -,-,- ISOAEC 13522-1:1997(E) 0 ISOAEC - New classes of applications: The widespread availability of remote access to audiovisual data processing systems open the way to new classes of applications such as interactive television, customised news programmes and archive materials. In the following paragraphs, the specific needs of communicating multimedia/hypermedia applications from these domains are examined, leading to a list of application requirements. This set of requirements constitutes the global framework of this part of ISOAEC 13522. 0.2 Multimedia/Hypermedia application requirements In the various domains presented above, interactive multimedia systems are perceived to have increased impact on users through their use of image, video and audio, in addition to traditional text information. The development of these systems is based upon support for multimedia information in the following areas: - Platforms: Emerging compression standards, such as JPEG (ISOAEC 10918) or MPEG (ISOAEC 11172, ISOAEC 13818), have enabled the development of dedicated hardware, which will soon be provided as a standard system resource. - Storage: The increasing capacity of magnetic and optical disks, combined with compression techniques, enables the storage of increasing amounts of high bandwidth information. - Communication: The increasing availability and bandwidth of digital transmission media, such as ISDN and other broadband telecommunication and broadcasting networks, enables the appropriate exchange of large amounts of data. Using these facilities, multimedia applications are anticipated to be designed to run on heterogeneous platforms and to be interconnected to offer multimedia services. These multimedia applications and services will use large quantities of structured multimedia objects resident in workstations, stored on digital interchange media and retrieved or distributed from remote sources through networks. These multimedia data will represent a significant investment and it is vital that the information should be applicable in a world of rapidly evolving systems and technologies. In particular, it is important that information should be interchangeable between the data structures supported by different applications. The following application requirements can be identified: a) multimedia database retrieval; b) frequent updates of multimedia data; c) manipulation of a set of data elements; d) creation of multimedia documents on a range of workstations; e) composition of multimedia data in time and space; f) ability to link part of a document with some other part of the same or another document in an open hyperdocument environment; g) synchronisation: 1) elementary synchronisation: two objects are synchronised with regard to the same reference origin time (parallel mode) or one with regard to the other (sequential mode); 2) chained synchronisation: a set of objects are presented one after another in the form of a chain; 3) cyclic synchronisation: one or more objects are repetitively presented; 4) conditional synchronisation: the presentation of an object is linked to the fulfilment of a condition; h) reuse of multimedia data by integration in different documents; xlii Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 04/02/2007 21:06:47 MDTNo reproduction or networking permitted without license from IHS -,-,- 0 ISOAEC ISO/IEC 13522-1:1997(E) i) exchange of multimedia data between heterogeneous systems; j) space wide range of users, including closed user groups; k) real-time interactivity, including acquisition of multimedia data; I) telecommunication of multimedia data; m) broadcast of multimedia data; n) wide range of data volumes and transfer rates; 0) access control, security; p) tariffing; q) copyright, licensing; r) wide range of support materials; s) use of a wide range of terminals and workstations, including devices with minimal resources; t) minimal resources: facilities that the interchange form must provide in order for a given set of objects, running in limited resources environments, to meet their functional specification as determined by the designer: 1) ease of specification: for specifying the minimum recommended resources needed by an MHEG application; 2) ease of application: minimum requirements of an application should be easily recognised by the negotiation process; 3) flexibility: the mechanism should be reliable across a broad range of system configurations and media formats; 4) informative rather than restrictive: the using application should have the final determination as to whether a given set of objects can be interpreted; 5) extensible/open: the representation should function correctly as new formats, classes, and application- dependent parameters are added; 6) scalability: trade-off among different application platform capabilities, for example, resolution enhancement relative to presentation time; 7) composition: the minimum resource requirements for a given MHEG application should be combinable in some consistent and predictable manner when applications are combined; 8) graceful degradation: the primary concern of minimal resource systems is the manner in which degradation can be handled; an application should be able to express its policy with regard to this issue, for example, by using scalability and related mechanisms; u) real-time interchange and presentation: 1) object placement optimisation: objects that are likely to be accessed simultaneously are adjacent from the standpoint of the access mechanism; 2) progressive access of objects: images may be retrieved and presented in increasing resolution for systems with significant presentation delay; scalable versions of objects may be represented and retrieved for systems with insufficient resources for full fidelity presentation; 3) partial object retrieval: large objects may be retrieved in several portions, since the entire content is not presented at one time; 4) object sequencing: the order in which objects are expected to be presented should be used by the access mechanism when insufficient throughput would lead to unacceptable delays for the whole object to be interchanged; 5) separate retrieval of object description and object content: the object description should be retrieved without necessarily retrieving the content so that the system can use information about a set of objects to optimise the access for this set and resources needed for the access can be prepared; xliii Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 04/02/2007 21:06:47 MDTNo reproduction or networking permitted without license from IHS -,-,- ISOAEC 13522-1:1997(E) 0 ISO/IEC 6) global object index: a table of all objects and their position in an object set should be provided to support fast lookup of objects; 7) object interleaving: objects that are to be retrieved simultaneously may be interleaved so that large objects do not cause delays for other objects; 8) resource requirements: that for retrieval and presentation by the target system should be available by lookup rather than by derivation; 9) aggregate retrieval: a collection of objects can be aggregated so that they can be retrieved by one step rather than through a series of requests; v) ability to reference individual media objects internally and externally; w) ability to navigate in a hypermedia fashion; x) ability to support arbitrary hyperlink transversal schemes. These requirements can be summarised in a set of generic needs: - Application designers and vendors require application portability in a multi-vendor environment. - Applications need handle multimedia information structured in such a way that real-time interactivity (including acquisition of multimedia data), as well as real-time interchange of multimedia data can be ensured. - Applications need compose and synchronise multimedia data in space and time. - Applications need be able to define links between multimedia data elements. - Applications need be able to reuse multimedia data by integration in different contexts. - Applications need be able to frequently update the multimedia data, as well as to manipulate a set of data elements. - Applications need be able to be interpreted on different systems, from minimal resources to non-limited resources systems. - Applications need be interchanged and presented in real-time. These requirements have been taken into account in defining the standard for multimedia and hypermedia information. 0.3 Rationale for standardisation of multimedia and hypermedia information The rationale for a standard defining multimedia and hypermedia information structures is based on the following considerations. - Standardisation only at the level of monomedia information is not sufficient to guarantee application portability. Applications do not use the monomedia data separately but must define an associated set of parameters that are necessary for presentation. (Such parameters may include identification of the encoding algorithm applied to the data, decoding parameters relevant to the data, optional attributes to be used for presentation). - Standardisation only at the level of monomedia information is not sufficient for the design and interchange of multimedia and hypermedia information. Multimedia and hypermedia applications rely on abstractions or data structures that provide features such as synchronisation links and logical links between monomedia data. - The design and management of multimedia and hypermedia applications in distributed environments is eased if the internal details of the information presentation are masked from the application by the use of appropriate abstractions. The application should deal only with functions such as management of information distribution, scheduling of presentation, management of the user dialogue, and other high-level activities. This part of ISO/IEC 13522 aims to provide generic multimedia/hypermedia information structures that fulfil these requirements and additionally are suited to: xliv Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 04/02/2007 21:06:47 MDTNo reproduction or networking permitted without license from IHS -,-,- 0 ISOAEC ISOAEC 13522-1:1997(E) - real-time presentation, i.e. using multimedia presentation and synchronisation facilities available on the application platform: - real-time interchange, i.e. using communication facilities available on the application platform; - final-form representation, i.e. in which the information is represented and coded for direct presentation without requiring additional processing of its structure. 0.4 Objectives of this part of ISO/IEC 13522 0.4.1 Interchange This part of ISO/IEC 13522 provides interchange facilities for various media types. The media data may be encoded according to other international standards, e.g. JPEG for still image, MPEG for video, or may be encapsulated using private or proprietary coding techniques. The interchange units defined by this part of ISOAEC 13522 are handled by the MHEG engine under the control of a using application. In order to support multimedia interchange, as opposed to the interchange of multiple media, this part of ISOAEC 13522 provides structures for the composition of different media types within a single unit of interchange. 0.4.2 Presentation This part of ISO/IEC 13522 supports final-form presentation of multiple media types. This part of ISOAEC 13522 provides facilities for the identification of the coding technique to enable the use of the appropriate presentation resources on a specific platform. In order to support multimedia presentation, as opposed to the presentation