- From: gregory j. rosmaita <oedipus@hicom.net>
- Date: Mon, 14 May 2001 14:11:30 -0400 (EDT)
- To: Anne Pemberton <apembert@erols.com>
- cc: w3c-wai-gl@w3.org
aloha, anne! Anne Pemberton wrote: > With my limited knowledge of specifics in technologies, we can go > either of two choices - 1) work to put everything onto each page, and have > people tripping over other folks' needs, or put some of the requirements on > a site, rather than a page level ... there will be pages of text and > illustrations perhaps with accompanying sound files, but multi-media would > be linked from a page "other modality page" rather than *ON* the other > modality page .... to which i reply: as lisa wrote in another thread, it is time that we, as a working group, disabused ourselves of the notion that addressing the accessibility needs of one group of users necessarily leads to the erection of barriers for others -- that logic runs counter to the whole exercise of drafting, testing, and promulgating web content accessibility guidelines... if i add an image to my page, then i need to ensure that its functionality and purpose is clear when the image isn't rendered; likewise, if i include an audio file, it is incumbent upon me as a page author, to provide a text transcript of the contents of the audio file, or -- if the file, for example, contains non-verbal information, a "long description" of its nature, function, and purpose... anne also wrote: > On the multi-media page, we need to specify the controls that are needed > for accessibility - such as the ability to stop, pause, back up a bit, play > forward, etc. If it is felt that these controls are needed on each and > every type of multi-media, then the guidelines need to specify the minimum > types of controls that are necessary. to which i reply that these are the types of control that are (properly) covered by the User Agent Accessibility Guidelines (UAAG), the last call draft of which can be found at: <http://www.w3.org/TR/uaag10/> while i have included a longer list of pertinent UAAG checkpoints as a postscript, the following, i believe, address the concerns you outlined: checkpoint 3.2 - configuration not to render multi-media except upon explicit user request; ability to have UA display/render each multi-media component individually on user request; P1 checkpoint 3.8 - ability to turn off individual multi-media components that are exposed through the UA by explicit user request as per 3.2; P3 checkpoint 4.4 - ability to slow presentation rate of audio & animations, including video; "audio and animations whose recognized role is to create a purely stylistic effect exempted, but refer to notes on 4.7 and explicit dependency on WCAG 1.0 (do not convey info through style alone); P1 checkpoint 4.5 - ability to stop, pause, resume, fast advance, & fast reverse audio & animations, including video; applies to content that is either rendered automatically or on explicit user request; "audio and animations whose recognized role is to create a purely stylistic effect exempted, but refer to notes on 4.8 and explicit dependency on WCAG 1.0 (do not convey info through style alone); P1 checkpoint 4.6 - user control of positioning/repositioning of text transcripts, collated transcripts, and captions; P1 checkpoint 4.7 - ability to slow presentation rate of audio & animations, including video for "audio and animations whose recognized role is to create a purely stylistic effect" (i.e. those exempted from 4.4); P2 checkpoint 4.8 - ability to stop, pause, resume, fast advance, & fast reverse audio & animations, including video, not covered by 4.5; P2 where WCAG enters the picture is in providing guidance to authors on how to integrate multi-media components into their pages so that the above-listed checkpoints apply -- i'm thinking in particular of the practice of embedding multi-media players in web pages, which often precludes anyone without a pointing device (or the ability to use one) from controlling the embedded multi-media player from the keyboard, since any keyboard input acts not on the embedded player, but upon the browser, since it is the browser that receives keyboard input and not the embedded player, since the browser doesn't have a "pass-through" mechanism, which the user could use to force the browser ignore the next keyboard input so that it can be received by the embedded player... i believe that this particular case is actually covered by UAAG checkpoints 1.1 (ensure that user can operate UA fully through keyboard input alone; P1); 9.2 (allow the user to move the content focus to any enabled element in the viewport, including disabled elements; P1); and 9.6 (allow user to move content focus to any enabled element in viewport, excluding disabled elements [special case of 9.2]; P2), but that is my personal reading of the document and does not represent a consensus on the part of the User Agent working group, of which i am a member... anne also commented: > I did include illustrations and sound files with the text page. I > don't feel there is any need for an "all text version" ... It is easy in > any/all? browsers to turn off the illustrations, and sounds files can be > controllable by the user (if by turning the speaker off if all else fails!) > ... So all these can reside on the same page... to which i reply that i don't think that anyone's being asked to provide an "all text version", but, rather, multi-media enhanced pages/documents/applications (in the XML sense of the word) that transform gracefully when support for particular multi-media components is either turned off or not available--that is, not supported by the browser being used to render the document source... moreover, turning off support for a content type (such as scripts, so as to prevent being taken unexpectedly to a new page whilst attempting to review the contents of a list box) as you suggest, is a far too draconian approach, which is why the User Agent Accessibility Guidelines address both configuration (don't show me any images) and control (show me just this particular image/hide this particular image/suppress this particular action) gregory. PS: my on-the-fly listing of UAAG checkpoints that appertain to control over multi-media components are: 2.3 - access to unrendered "conditional content" (P1) 2.4 - ability to control timed events (P1) 2.5 - configuration/control over text transcripts, captions, and audio description 2.6 - respect synchronization cues during rendering (P1) 2.7 - repair text for conditional content required by spec, but which author has failed to provide (P2) 2.8 - configuration for handling "null" conditional content (P3) 2.9 - configuration to render all conditional content automatically 3.1 - ability to configure UA not to render background images/alert if background available but not rendered (P1) 3.2 - configuration not to render multi-media except upon explicit user request; ability to have UA display/render each multi-media component individually on user request; P1 3.3 - ability to configure UA to render animated or blinking text as motionless, unblinking text (P2) 3.7 - configuration not to render images with option to have UA substitute a placeholder in context for unrendered images; ability to have UA render original content when placeholders rendered (P2) 3.8 - once user has viewed original author-supplied content associated with placeholder, allow user to turn off rendering of author-supplied content 4.4 - ability to slow presentation rate of audio & animations, including video; "audio and animations whose recognized role is to create a purely stylistic effect exempted, but refer to notes on 4.7 and explicit dependency on WCAG 1.0 (do not convey info through style alone); P1 4.5 - ability to stop, pause, resume, fast advance, & fast reverse audio & animations, including video; applies to content that is either rendered automatically or on explicit user request; "audio and animations whose recognized role is to create a purely stylistic effect exempted, but refer to notes on 4.8 and explicit dependency on WCAG 1.0 (do not convey info through style alone); P1 4.6 - user control of positioning/repositioning of text transcripts, collated transcripts, and captions; P1 4.7 - ability to slow presentation rate of audio & animations, including video for "audio and animations whose recognized role is to create a purely stylistic effect" (i.e. those exempted from 4.4); P2 4.8 - ability to stop, pause, resume, fast advance, & fast reverse audio & animations, including video, not covered by 4.5; P2 4.9 - global configuration & control over volume of all audio with option to override author-specified volumes and UA default volume settings (P1) 4.10 - allow independent control of volumes of each distinct audio source when more than one audio source is playing 4.12 - control of synthesized speech volume independent of other audio (for example, turn down volume on background sound without affecting voice output levels) ---------------------------------------------------------------- ACCOUNTABILITY, n. The mother of caution. -- Ambrose Bierce, _The Devil's Dictionary_ ---------------------------------------------------------------- Gregory J. Rosmaita: oedipus@hicom.net Camera Obscura: http://www.hicom.net/~oedipus/ VICUG NYC: http://www.hicom.net/~oedipus/vicug/index.html Read 'Em & Speak: http://www.hicom.net/~oedipus/books/index.html ----------------------------------------------------------------
Received on Monday, 14 May 2001 14:11:39 UTC