From C.Cartledge@sheffield.ac.uk Tue Nov 30 18:54:20 1993 Received: from osiris.dknet.dk by dkuug.dk with SMTP id AA06635 (5.65c8/IDA-1.4.4j for ); Tue, 30 Nov 1993 18:20:30 +0100 X400-Received: by mta osiris.dknet.dk in /PRMD=minerva/ADMD=dk400/C=dk/; Relayed; Tue, 30 Nov 1993 18:20:23 +0100 X400-Received: by /PRMD=uk.ac/ADMD= /C=gb/; Relayed; Tue, 30 Nov 1993 18:20:53 +0100 X400-Received: by /PRMD=UK.AC/ADMD= /C=GB/; Relayed; Tue, 30 Nov 1993 18:14:28 +0100 X400-Received: by /PRMD=UK.AC/ADMD= /C=GB/; Relayed; Tue, 30 Nov 1993 18:02:58 +0100 X400-Received: by /PRMD=UK.AC/ADMD= /C=GB/; Relayed; Tue, 30 Nov 1993 17:54:20 +0100 Date: Tue, 30 Nov 1993 17:54:20 +0100 X400-Originator: C.Cartledge@sheffield.ac.uk X400-Recipients: sc24@dkuug.dk X400-Mts-Identifier: [/PRMD=uk.ac/ADMD= /C=gb/; Message-Id: To: SC24 list , IST/31 , S.Price@sheffield.ac.uk Subject: IST/18 comments on NP on PREMO (fwd) Reply-To: Chris Cartledge Original-Sender: Chris Cartledge Mime-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=US-ASCII X-Charset: ASCII X-Char-Esc: 29 Colleagues, I have discussed the matter with Steve Price (UK SC18) and in the absence of other input (other than the earlier acceptance of the document with no comment by UK SC24 experts) have jointly agreed the following: Title: UK comments to JTC1 on NP on PREMO (Presentation Environments for Multimedia Objects) Date 1993-11-30 (JTC1 N2627) : Revised text of a proposal for a New Work Item on Presentation Environments for Multimedia Objects (PREMO) The UK votes YES to this NP and does not want to see technical work postponed further. However some UK experts have serious reservations about the direction of the work and so the UK requests that the Working Group address the following issues at an early date. In particular, in respect of ODA, the UK suggests that there be a joint meeting of SC18 and SC24 experts to determine the suitability of ODA (either itself or the concepts) as a storage and transfer mechanism for PREMO. There also need to be joint meetings to ensure that MHEG and PREMO experts can agree the relationship and interfaces between PREMO and MHEG. The other comments are under three headings: 1. duplication of existing standards 2. support of existing standards 3. general structure of the proposed work 1. DUPLICATION OF EXISTING STANDARDS The revised text of the NP does not adequately address the previously raised issue of duplication of standard specifications. The work of the PREMO group must be directed so that that it builds upon existing standards whereever possible rather than duplicating them as the current text might suggest. ISO 8613 : 1989 (ODA) specifies the structuring and relationships of multiple content types. Importantly it also standardises the layout and presentation of multiple contents in relationship with each other. ISO/IEC 8613-14, currently at the stage of DIS, adds provision for time and hypermedia relationships. The above is all defined in an object oriented manner permitting access to and handling of individual and composite objects. The text of the NP would suggest that SC24 will be re-invent these features under the PREMO work item. Instead the issues need to be examined jointly with SC18 experts. ISO/IEC 135221-1 (MHEG), currently at the stage of DIS, specifies similar structuring, layout and presentation facilities for a real-time interchange environment. The relationship between ODA and MHEG is clear and a technical report on their interworking is in preparation. Both ODA and MHEG have been developed in collaboration with ITU-T. Again SC24 needs to agree a relationship with MHEG experts. 2. SUPPORT FOR EXISTING STANDARDS The revised text does not demonstrate that the resulting work will fully support existing standards. The PREMO work must address the issue of interfaces to support existing standards and not constrain itself to a restricted set of applications. The added value aspect of PREMO is the specification of an interface to an environment in which all, many as yet unknown, data formats can be presented in relation to each other. In this regard the proposal is weak because it constrains itself to specific structures and models. To quote from clause 2.2.7, "HyperODA and PREMO could achieve interoperability if HyperODA were specified as a HyTime application". HyperODA (ISO/IEC DIS 8613-14) is not a HyTime application, neither is MHEG and neither will be many other hypermedia data formats and consequently PREMO is not serving the needs of a wide range of applications. 3. GENERAL STRUCTURE OF THE PROPOSED WORK The NP contains an open ended statement of extensions that will be developed (see clause 2.2.1). Each item of extension should be the explicit subject of future NPs.