Prime M J

English

ePubs: the open archive for STFC research publications

Adapting multi media information for   internationalization and for users with disabilities3rd ERCIM Workshop, "User Interfaces For all"Martin PrimeM.Prime@rl.ac.ukRutherford Appleton Laboratory,Chilton, Didcot, Oxfordshire, OX11 0QX, UKAbstract: There is considerable pressure to make information more accessible, both tousers with disabilities, and to users around the world. One focus of informationdissemination and adaptation is the WWW. Current changes to browsers and contentmainly effect HTML text, not multimedia. HMML is the proposed WWW standard forsynchronised multimedia including video, audio, and media which are themselvesstatic. The Chameleon editor produces HMML and provides conditionals on theselection of channels for a particular presentation. This provides support for theadaptability of multimedia by rules to select the one appropriate for the users language,presentation and other adaptation needs.INTRODUCTIONWe live in an international world where the multilingual policy adopted by Europe is a criticaltest for system developers to support global information dissemination. The World Wide Webstill has a bias toward English and the western-european writing system. But modern business,research, and interpersonal communication is increasingly conducted in other writing systemsand languages. Web connectivity and use is continuing to grow rapidly all around the world,including countries and communities that have a low tolerance or understanding of English.While English remains prevalent on the Web, many companies are today investing - orconsidering investing - time and money into localizing content on the Web for non-Englishspeaking audiences. The Web must and is being enhanced to meet the needs of a globalcommunity.The first step to a global web, is to support HTML internationalisation, which is initially beingaddressed by W3C through widening the character set to incorporate Unicode to present awide range of character sets (see the draft HTML internationalisation standard atftp://ds.internic.net/rfc/rfc2070.txt). Obviously once this mechanism is in place, many furtherlayers of internationalisation are required in order to address different cultures and styles ofinteraction.An Internationalized & Multilingual Web should have the traditional facilities ofInternationalization and more advanced facilities needed for Language Engineering. Forexample, clients should have a language menu that shows in which other linguistic versionsthe currently displayed document is available; or clients should be capable of displaying andmoving in sync side by side, two linguistic versions of the same document.Parallel Hypertext is an extension of the hypertext paradigm to natural languages. Forexample, a user looking at a document in English should be able to obtain the Spanishtranslation in a transparent way; i.e., just by selecting the Spanish option in a language menuand not by selecting an anchor embedded in the English version. For this, the system mustknow about languages; i.e., the same in another language. The same property of alignness inParallel Texts applied to Parallel Hypertext.As well as internationalisation, there is also pressure on the WWW to address the informationneeds of users with disabilities. The motivation for addressing accessibility for the disabled inthe US is the "Americans with Disabilities Act" of 1990(gopher://trace.wisc.edu/00/ftp/PUB/TEXT/ADA_INFO/LAW/ADA.TXT). This was draftedin order to establish a clear and comprehensive prohibition of discrimination on the basis ofdisabilityW3C has its own Web Accessibility Initiative (http://www.w3c.org/WAI/) while other bodiesare already establishing an active infrastructure, such as the US National Centre forAccessible Media Symbol for the WWW(http://www.boston.com/wgbh/pages/ncam/symbolwinner.html) awarded to sites conformingto the Unified Web Site Accessibility Guidelines(http://www.trace.wisc.edu/text/guidelns/htmlguide/htmlguide.htm). Several large fundedprojects investigating accessibility of the Web at University of Toronto(http://www.toronto.ca/atrc/), Yuri Rubinsky Insight Foundation(http://www.yuri.org/webable/), as well as work undertaken at the major browser developersto make their browsers voice accessible (e.g. Microsoft athttp://www.microsoft.com/ie/most/howto/access.htm, or Mosaic athttp://www.staff.uiuc.edu/~jongund/access-browsers.html) or making them more usable byscreen readers (e.g. http://www.trace.wisc.edu/text/guidelns/browser/screen.html). In additionto basic browsers and htm page design accessibility is also being investigated for richermultimedia formats including the virtual reality language VRML(http://www.toronto.ca/atrc/rd/vrml/main.html) and the hypermedia language HMML.HMML - SYNCHRONISED MULTIMEDIA LANGUAGEThe Sychronised Multimedia working group of W3C has developed the specification of a newlanguage for synchronising audio, video and other media presentations on the web (HMML).HMML is the proposed WWW standard for presenting Synchronised Multimedia Information(see http://www.w3c.org/AudioVideo/Activity.html). The current HTML based webtechnology is limited when it comes to creating continuous multimedia presentations. Forthese applications, content authors need to express things like "five minutes into thepresentation, show image X and keep it on the screen for ten seconds". More generallyspeaking, there must be a way to describe the synchronization between the different media(audio, video, text, images) that make up a continuous multimedia presentation.HMML is a declarative format for time representation and media synchronisation which,when supported by real time transport protocols between client and server, such as RTSP (seehttp://www.cs.columbia.edu/~hgs/rtsp/) calling RTP (seehttp://www.cs.columbia.edu/~hgs/rtp/), supports the synchronisation of media channels. Thecurrent draft of HMML (see http://www.w3c.org/AudioVideo/Group/WD-symm-format.html)is based on the CMIF format originally developed by CWI [1] and further refined in the EspritChameleon project [2].The Chameleon project has developed an editor and viewer for the HMML format, andexplored various options for layering choice mechanisms on top of the transport andsynchronisation layers which will support the options required for internationalisation andaccessibility.ADAPTING SYNCHRONISED MULTIMEDIAMuch of the work done on adaptation in the web is text, or HTML based, more work isneeded in the area of multimedia in general. A system should be capable of supportingdifferent cultures, natural languages, disabled users and Language Engineering facilities suchas Parallel Texts. Internationalization permeates most subsystems: client, transmission, server,data and authoring. (Language Engineering is the application of informatics to naturallanguages).There are also yet other, wider issues of adaptive multimedia, which also need to beaddressed.If one is producing a document accessible to different languages or to users with differentpresentation needs it is possible for the author at editing time to produce different editions foreach identified group of end users. This requires considerable authoring effort, but alsorequires storage of each edition, and the identification of the end user group for which theedition is appropriate. When documents are updated, all editions must be updated together inorder to maintain consistency. This approach is required to produce paper text documents inmultiple languages, but for multimedia documents, where the costs of producing media suchas video are considerably more than for paper text it is both more complex andexpensive.Films and videos can be dubbed in many languages, and like texts, editors canproduce multiple versions of the film and associated national soundtrack which must be storedand distributed to their respective markets. However, the production, inventory anddistribution costs for multiple editions of multimedia documents are prohibitive for all but themost expensive end-user product - best selling feature films and games.The alternative approach is to have a mechanism where one document base can exist and thenbe tailored at the time of presentation. For multimedia, a single digital video can be stored,with many associated, labelled national soundtracks, and the national version of the audio-video edition only comes together at presentation time, when a user has identified theirlanguage requirement.This makes sense in terms of product costs and presentationmaintenance for multimedia. It therefore makes the model attractive to the people whoultimately will need to foot the bill. The Chameleon system [2] through this mechanismsupports parallel language facilities [3].For multimedia Chameleon provides presentation time synchronisation as supported byHMML. Presentation time synchronisation of channels allows Chameleon to offer the abilityfor authors & publishers to keep a single copy of the document and vary it at presentation timein the same way that style sheets [4][5] offer support for run time variation of HTML texturaldocuments.Through the approach of producing a single multimedia document containingmany channels the Chameleon editor is able to support both many national versions as well asthose for differently-abled users through the use of adaptation rules to select the appropriatechannels.User requirements need to be gathered for the version to be presented to the individual user,though this can be carried out through a minimally intrusive dialogue or from the users storedprofile. Chameleon provides the author with control of the available resources, the channelsprovide a view of the media objects mapped onto the available logical resources. By supplyingan extra layer above the physical resources the author is able to describe the presentation in asystem-independent way. It is up to the player, optimized for a particular hardwareconfiguration, to interpret the logical channels and assign the media objects to the availablephysical output devices. It is possible for the author to add channels to Chameleon if the onethey need does not exist. The author can then produce a document that can be configuered bythe user. For example a blind user may chose to use the sound channel to present the textrather than the display text channel. These choices can be made at run time by the user.The trivial adaptation rules introduced so far are of the form:     1) for visually handicapped users -a) increase font sizes, and use san-serif fonts for textb) select the audio channels for textc) do not present images     2) For internationalisation -a) select text & audio channels using national language & typography.Obviously, a scale of visual and auditory handicaps exist, for which different triggers andrules are required. There is no current agreement on a universal set of trigger tags fornationality or disability, although these are under negotiation by the XML community.Since different browser manufacturers (e.g. Netscape and Microsoft) have chosen toimplement cascading style sheets in different ways, which derive information from systemwide profiles on some platforms, and require information to be stored in browser’s own userprofile on others it is not possible to state a general method by which users will select the tagsto be used as triggers to the conditional statements in the HMML structure. However, allbrowser implementations will provide the tags to support the conditionals through their stylesheets.FURTHER ADAPTATION ISSUESChameleon can solve the run time selection of channels for information presentation side ofthe problem, but more work is in progress to provide solutions to other adaptation problems tomeet the needs of an international or disabled audience of multimedia presentations. Some ofthese problems are listed here so that adaptation rules to solve them for synchronisedmultimedia systems such as Chameleon [1] can be discussed at the workshop.Multilingual Aligned Text (MAT)A MAT is a record with one Linguistic Object per language field (English, Spanish, German,etc) that are the equivalence (usually the translation) of each other. MAT’s give rise to manyproblems of alignment and presentation since the translations do not occupy the same space ororientation.Date & Time and other structural conventionsExample, the internal representation could be 19951231 and the external representation couldbe December 31th 1995, or 31-12-1995 [6].Multilingual TypographyIt can be difficult to present some languages as the typography does not exist on thepresentation machine. For example bidirectional formatting control is important for languagessuch as Hebrew and Arabic. Although Chameleon would adapt to the appropriate channels ifthey are available on the end-user machine for various exotic typographic conventions, it isnot able to introduce all such channels itself.General Cultural ProblemsMany of the deeper cultural problems relate to the content of what is being presented, as wellas to conventions of comprehending it. Obviously, the acceptability of multimediapresentations for violence, sexual pornography or political content varies with culture, but sodo many of the conventions used within the presentations. Although the cinema distribution isglobal for Hollywood films, they use different conventions to those Indian films fromBollywood, which make each incomprehensible to the wrong audience. The selection ofcontent defined by pragmatic conventions is outside the scope of Chameleon, since it relies onPICS servers to rate the content. However, once again the use of multiple channels cansupport the run-time selection of the most appropriate content for a particular user - if any isavailable.CONCLUSIONChameleon suppports the editing and presentation of distributed multimedia documentsthrough HMML. HMML describes the structure of a multimedia document, supportingbinding at run time rather than at creation time. Chameleon introduces conditional statementswhich allow channels to be selected at run time depending on the user nationality,presentation station capabilities, and ultimately, user abilities, thereby accommodatingdisability. The conditional statements select the channels appropriate for the user atpresentation time based on information available to the browser through cascading stylesheets, browser or system wide user profiles.We are currently developing guidelines for authors to state the appropriate selection tags forthe conditional statements, and the appropriate conditional statements for internationalisationand the support of users with different disabilities. It is hoped that the workshop will providefurther guidance on the details of these tags and selection rules for continuous media beyondHTML.REFERENCES [1] Hardman, L. and Bulterman, D. Structured Multimedia Authoring. Proceedings of theACM Multimedia ’93 (Anaheim, CA), August 1993.>@ (XURSHDQ &RPPLVVLRQ &KDPHOHRQ $XWKRULQJ 6XSSRUW IRU $GDSWLYH 0XOWLPHGLD’RFXPHQWV&(&(635,7,93URMHFW>@ +DUGPDQ / %XOWHUPDQ ’ 	 * YDQ 5RVVXP 7KH $PVWHUGDP +\SHUPHGLD 0RGHO$GGLQJ7LPHDQG&RQWH[WWRWKH’H[WHU0RGHO&$&0)HE>@ +0NRQ :LXP /LH &DVFDGLQJ 6W\OH 6KHHWV OHYHO KWWSZZZZRUJSXE:::755(&&66’HFHPEHU>@ 2VVHQEUXJJHQ - +DUGPDQ / 5XWOHGJH / (OLHQV $ 6W\OH VKHHW VXSSRUW IRUK\SHUPHGLDGRFXPHQWV+\SHUWH[W$SULO>@0LVKD:ROI&KDUOHV:LFNVWHHG’DWHDQG7LPH)RUPDWV KWWSZZZZRUJ75127(GDWHWLPHKWPO6HSWHPEHU

Adapting Multimedia Information for Internationalisation and; for Users with Disabilities

Abstract

Similar works

Full text

Available Versions

ePubs: the open archive for STFC research publications