- From: Maciej Stachowiak <mjs@apple.com>
- Date: Fri, 05 Nov 2010 10:27:28 +0100
- To: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
- Cc: Geoff Freed <geoff_freed@wgbh.org>, Frank Olivier <Frank.Olivier@microsoft.com>, "public-html@w3.org" <public-html@w3.org>, "public-html-a11y@w3.org" <public-html-a11y@w3.org>
We don't necessarily need super short all-caps tags. Here are some possible names in plain language: HTML5 Spec Requirement HTML5 Spec Requirement (already addressed) Timed Text Format Requirement UA Guidelines Requirement Regards, Maciej On Nov 5, 2010, at 3:11 AM, Silvia Pfeiffer wrote: > I actually used TTEXT (notice the 'E') and I first thought about TEXT, > but it needed something with time in it. How about CUE? > > Silvia. > > On Fri, Nov 5, 2010 at 12:56 PM, Geoff Freed <geoff_freed@wgbh.org> wrote: >> >> Hi, Frank and Silvia: >> >> I actually suggest that you *not* call it TTXT because, ironically, TTXT is >> already in use as the name of another timed-text format: >> http://gpac.sourceforge.net/doc_ttxt.php#ttxt . Maybe call it TRACKDETAIL? >> >> Geoff/NCAM >> >> >> >> On 11/4/10 5:19 PM, "Silvia Pfeiffer" <silviapfeiffer1@gmail.com> wrote: >> >> Maybe this classification is more useful in the Checklist [1] than the >> one we have there currently for "types of technologies affected"? >> >> I would, however, suggest calling the Text track format details TTEXT >> and not TRACK, since track is now the keyword for the markup in HTML5. >> >> [1] http://www.w3.org/WAI/PF/HTML/wiki/Media_Accessibility_Checklist >> >> Cheers, >> Silvia. >> >> >> On Fri, Nov 5, 2010 at 3:55 AM, Frank Olivier >> <Frank.Olivier@microsoft.com> wrote: >>> >>> Re http://www.w3.org/2010/11/04-html-wg-minutes.html >>> >>> Members of HTML WG and media a11y reviewed the >>> http://www.w3.org/WAI/PF/HTML/wiki/Media_Accessibility_Requirements >>> requirements >>> >>> We sorted the requirements into the following categories: >>> * UX: User agent user experience requirement >>> * SPECNEW: New requirements for the HTML5 specification >>> * SPECCED: Already in the HTML5 specification >>> * TRACK: Text track format detail - something that should be specced >>> in the track format, not the HTML spec >>> * NO: Not an issue we will address in the W3C >>> >>> >>> Of the 119 requirements in the document: >>> SPECNEW 11 items (9% of total) >>> SPECCED 21 (18%) >>> TRACK 24 (20%) >>> NO 4 (3%) >>> UX 73 (61%) >>> >>> Detailed list: >>> NO: (DV-9) Allow the author to use a codec which is optimized for voice >>> only, rather than requiring the same codec as the original soundtrack.Does >>> not seem like a UA issue: >>> NO: (KA-3) The author would be able to choose any/all of the controls, >>> skin them and position them. Needs discussion' kill >>> NO: (KA-5) The scripted and native controls must go through the same >>> platform-level accessibility framework (where it exists), so that a user >>> presented with the scripted version is not shut out from some expected >>> behavior. >>> NO: (PP-1) This necessitates a clear and unambiguous declared format, so >>> that existing authoring tools can be configured to export finished files in >>> the required format. >>> SPECCED, UX: (CA-2) Support the synchronisation of multitrack audio either >>> within the same file or from separate files - preferably both. >>> SPECCED: (API-1) The existence of alternative-content tracks for a media >>> resource must be exposed to the user agent. >>> SPECCED: (API-2) Since authors will need access to the alternative content >>> tracks, the structure needs to be exposed to authors as well, which requires >>> a dynamic interface. >>> SPECCED: (API-3) Accessibility APIs need to gain access to alternative >>> content tracks no matter whether those content tracks come from within a >>> resource or are combined through markup on the page. >>> SPECCED: (CA-1) Support clear audio as a separate, alternative audio track >>> from other audio-based alternative media resources. >>> SPECCED: (CC-22) Support captions that are provided inside media resources >>> as tracks, or in external files. >>> SPECCED: (CC-26) Support multiple tracks of foreign-language subtitles in >>> different languages. >>> SPECCED: (CC-27) Support live-captioning functionality. Addressed via API >>> SPECCED: (CN-4) Support third-party provided structural navigation markup. >>> SPECCED: (CNS-4) Producers and authors may optionally provide additional >>> access options to identified structures, such as direct access to any node >>> in a table of contents. [May be done with cue range] >>> SPECCED: (DAC-4) Synchronized alternatives for time-based media (e.g., >>> captions, descriptions, sign language) can be rendered at the same time as >>> their associated audio tracks and visual tracks (UAAG 2.0 3.1.3). >>> SPECCED: (DV-3) Support multiple description tracks (e.g., discrete tracks >>> containing different levels of detail). >>> SPECCED: (DV-4) Support recordings of real human speech as a track of the >>> media resource, or as an external file. >>> SPECCED: (KA-3) All functionality available to native controls must also >>> be available to scripted controls. >>> SPECCED: (PP-1) Support existing production practice for alternative >>> content resources, in particular allow for the association of separate >>> alternative content resources to media resources. Browsers cannot support >>> all forms of time-stamp formats out there, just as they cannot support all >>> forms of image formats (etc.). >>> SPECCED: (PP-4) Typically, alternative content resources are created by >>> different entities to the ones that create the media content. They may even >>> be in different countries and not be allowed to re-publish the other one's >>> content. It is important to be able to host these resources separately, >>> associate them together through the Web page author, and eventually play >>> them back synchronously to the user. >>> SPECCED: (SL-4) Support multiple sign-language tracks in several sign >>> languages. >>> SPECCED: (T-1) Support the provisioning of a full text transcript for the >>> media asset in a separate but linked resource. where the linkage is >>> programmatically accessible to AT. >>> SPECNEW, SPECCED: (SL-1) Support sign-language video either as a track as >>> part of a media resource or as an external file. >>> SPECNEW, SPECCED: (SL-2) Support the synchronized playback of the >>> sign-language video with the media resource. >>> SPECNEW, TRACK: (CC-5) Support positioning in all parts of the screen - >>> either inside the media viewport but also possibly in a determined space >>> next to the media viewport. This is particularly important when multiple >>> captions are on screen at the same time and relate to different speakers, or >>> when in-picture text is avoided. >>> SPECNEW, TRACK: (CN-1) Provide a means to structure media resources so >>> that users can navigate them by semantic content structure. >>> SPECNEW, UX: (CC-25) Support edited and verbatim captions, if available. >>> SPECNEW, UX: (DV-8) Allow the author to provide fade and pan controls to >>> be accurately synchronized with the original soundtrack. >>> SPECNEW: (CN-3) Support both global navigation by the larger structural >>> elements of a media work, and also the most localized atomic structures of >>> that work, even though authors may not have marked-up all levels of >>> navigational granularity. >>> SPECNEW: (CN-6) Support direct access to any structural element, possibly >>> through URIs. [Media fragment-like issue] >>> SPECNEW: (CNS-1) All identified structures, including ancillary content as >>> defined in "Content Navigation" above, must be accessible with the use of >>> "next" and "previous," as refined by the granularity control. [May be >>> handled with cue ranges] >>> SPECNEW: (DAC-2) The user has a global option to specify which types of >>> alternative content by default and, in cases where the alternative content >>> has different dimensions than the original content, how the layout/reflow of >>> the document should be handled. (UAAG 2.0 3.1.2). [Probably minimal spec >>> text required: Media queries would work nicely here; also UX issue (user >>> sets media query to match)] >>> SPECNEW: (DAC-5) Non-synchronized alternatives (e.g., short text >>> alternatives, long descriptions) can be rendered as replacements for the >>> original rendered content (UAAG 2.0 3.1.3). >>> TRACK, UX: (CC-16) Use conventions that include inserting left-to-right >>> and right-to-left segments within a vertical run (e.g. Tate-chu-yoko in >>> Japanese), when rendered as text in a top-to-bottom oriented language. >>> TRACK, UX: (CC-19) Present the full range of typographical glyphs, layout >>> and punctuation marks normally associated with the natural language's >>> print-writing system. >>> TRACK, UX: (CC-21) Permit the distinction between different speakers. >>> TRACK, UX: (ECC-2) Support hyperlinks and other activation mechanisms for >>> supplementary data for (sections of) caption text. >>> TRACK, UX: (ECC-3) Support text cues that may be longer than the time >>> available until the next text cue and thus provide overlapping text cues. >>> TRACK, UX: (ECC-4) It needs to be possible to define timed text cues that >>> are allowed to overlap with each other in time and be present on screen at >>> the same time >>> TRACK: (CC-10) Render a background in a range of colors, supporting a full >>> range of opacities. >>> TRACK: (CC-11) Render text in a range of colors. >>> TRACK: (CC-14) Allow the use of mixed display styles-- e.g., mixing >>> paint-on captions with pop-on captions-- within a single caption cue or in >>> the caption stream as a whole. >>> TRACK: (CC-17.1) Represent content of different natural languages. In some >>> cases the inclusion of a few foreign words form part of the original >>> soundtrack, and thus need to be in the same caption resource. >>> TRACK: (CC-18) Represent content of at least those specific natural >>> languages that may be represented with [Unicode 3.2], including common >>> typographical conventions of that language (e.g., through the use of >>> furigana and other forms of ruby text). >>> TRACK: (CC-2) Allow the author to specify erasures, i.e., times when no >>> text is displayed on the screen (no text cues are active). >>> TRACK: (CC-20) Permit in-line mark-up for foreign words or phrases. >>> TRACK: (CC-3) Allow the author to assign timestamps so that one >>> caption/subtitle follows another, with no perceivable gap in between. >>> TRACK: (CC-4) Be available in a text encoding. >>> TRACK: (CC-8) Allow the author to specify line breaks. >>> TRACK: (CC-9) Permit a range of font faces and sizes. >>> TRACK: (CN-2) The navigation track should provide for hierarchical >>> structures with titles for the sections. >>> TRACK: (DV-14) Support metadata, such as copyright information, usage >>> rights, language, etc. >>> TRACK: (ECC-1) Support metadata markup for (sections of) timed text cues. >>> TRACK: (PP-2) Support the association of authoring and rights metadata >>> with alternative content resources, including copyright and usage >>> information. [Move to ATAG?] >>> TRACK: (PP-3) Support the simple replacement of alternative content >>> resources even after publishing. >>> UX, SPECCED: (MD-5) If the user can modify the state or value of a piece >>> of content through the user interface (e.g., by checking a box or editing a >>> text area), the same degree of write access is available programmatically >>> (UAAG 2.0 2.1.5). >>> UX: (CA-3) Support separate volume control of the different audio tracks. >>> UX: (CC-1) Render text in a time-synchronized manner, using the media >>> resource as the timebase master. >>> UX: (CC-12) Enable rendering of text with a thicker outline or a drop >>> shadow to allow for better contrast with the background. >>> UX: (CC-13) Where a background is used, it is preferable to keep the >>> caption background visible even in times where no text is displayed, such >>> that it minimises distraction. However, where captions are infrequent the >>> background should be allowed to disappear to enable the user to see as much >>> of the underlying video as possible. >>> UX: (CC-15) Support positioning such that the lowest line of captions >>> appears at least 1/12 of the total screen height above the bottom of the >>> screen, when rendered as text in a right-to-left or left-to-right language >>> UX: (CC-17.2) Also allow for separate caption files for different >>> languages and on-the-fly switching between them. This is also a requirement >>> for subtitles. >>> UX: (CC-23) Ascertain that captions are displayed in sync with the media >>> resource. >>> UX: (CC-24) Support user activation/deactivation of caption tracks. >>> UX: (CC-6) Support the display of multiple regions of text simultaneously. >>> UX: (CC-7) Display multiple rows of text when rendered as text in a >>> right-to-left or left-to-right language. >>> UX: (CN-10) Support that in bilingual texts both the original and >>> translated texts can appear on screen, with both the original and translated >>> text highlighted, line by line, in sync with the audio narration. >>> UX: (CN-5) Keep all content representations in sync, so that moving to any >>> particular structural element in media content also moves to the >>> corresponding point in all provided alternate media representations >>> (captions, described video, transcripts, etc) associated with that work. >>> UX: (CN-7) Support pausing primary content traversal to provide access to >>> such ancillary content in line. >>> UX: (CN-8) Support skipping of ancillary content in order to not interrupt >>> content flow. >>> UX: (CN-9) Support access to each ancillary content item, including with >>> "next" and "previous" controls, apart from accessing the primary content of >>> the title. >>> UX: (CNS-2) Users must be able to discover, skip, play-in-line, or >>> directly access ancillary content structures. >>> UX: (CNS-3) Users need to be able to access the granularity control using >>> any input mode, e.g. keyboard, speech, pointer, etc. >>> UX: (DAC-1) The user has the ability to have indicators rendered along >>> with rendered elements that have alternative content (e.g., visual icons >>> rendered in proximity of content which has short text alternatives, long >>> descriptions, or captions). In cases where the alternative content has >>> different dimensions than the original content, the user has the option to >>> specify how the layout/reflow of the document should be handled. (UAAG 2.0 >>> 3.1.1). >>> UX: (DAC-3) The user can browse the alternatives and switch between them. >>> UX: (DAC-6) Provide the user with the global option to configure a cascade >>> of types of alternatives to render by default, in case a preferred >>> alternative content type is unavailable. >>> UX: (DAC-7) During time-based media playback, the user can determine which >>> tracks are available and select or deselect tracks. These selections may >>> override global default settings for captions, descriptions, etc. (UAAG 2.0 >>> 4.9.8) >>> UX: (DAC-8) Provide the user with the option to load time-based media >>> content such that the first frame is displayed (if video), but the content >>> is not played until explicit user request. >>> UX: (DV-1) Provide an indication that descriptions are available, and are >>> active/non-active. >>> UX: (DV-10) Allow the user to select from among different languages of >>> descriptions, if available, even if they are different from the language of >>> the main soundtrack. >>> UX: (DV-11) Support the simultaneous playback of both the described and >>> non-described audio tracks so that one may be directed at separate outputs >>> (e.g., a speaker and headphones). >>> UX: (DV-12) Provide a means to prevent descriptions from carrying over >>> from one program or channel when the user switches to a different program or >>> channel. >>> UX: (DV-13) Allow the user to relocate the description track within the >>> audio field, with the user setting overriding the author setting. The >>> setting should be re-adjustable as the media plays. >>> UX: (DV-2) Render descriptions in a time-synchronized manner, using the >>> media resource as the timebase master. >>> UX: (DV-6) Allow the user to independently adjust the volumes of the audio >>> description and original soundtracks, with the user's settings overriding >>> the author's. >>> UX: (DV-7) Permit smooth changes in volume rather than stepped changes. >>> The degree and speed of volume change should be under provider control. >>> UX: (ECC-5) Allow users to define the reading speed and thus define how >>> long each text cue requires, and whether media playback needs to pause >>> sometimes to let them catch up on their reading. >>> UX: (EVD-1) Support detailed user control as specified in (TVD-4) for >>> extended video descriptions. >>> UX: (EVD-2) Support automatically pausing the video and main audio tracks >>> in order to play a lengthy description. >>> UX: (EVD-3) Support resuming playback of video and main audio tracks when >>> the description is finished. >>> UX: (KA-1) Support operation of all functionality via the keyboard on >>> systems where a keyboard is (or can be) present (Needs better text), and >>> where a unique focus object is employed. This does not forbid and should not >>> discourage providing mouse input or other input methods in addition to >>> keyboard operation. (UAAG 2.0 4.1.1) >>> UX: (KA-2) Support a rich set of native controls for media operation, >>> including but not limited to play, pause, stop, jump to beginning, jump to >>> end, scale player size >>> UX: (KA-4) It must always be possible to enable native controls regardless >>> of the author preference to guarantee that such functionality is available >>> UX: (MD-2) Ensure accessibility of all user-interface components including >>> the user interface, rendered content, and alternative content; make >>> available the name, role, state, value, and description via a >>> platform-accessibility architecture. (UAAG 2.0 2.1.2) >>> UX: (MD-3) If a feature is not supported by the accessibility >>> architecture(s), provide an equivalent feature that does support the >>> accessibility architecture(s). Document the equivalent feature in the >>> conformance claim. (UAAG 2.0 2.1.3) >>> UX: (MD-4) If the user agent implements one or more DOMs, they must be >>> made programmatically available to assistive technologies. (UAAG 2.0 2.1.4) >>> This assumes the video element will write to the DOM. >>> UX: (MD-6) If any of the following properties are supported by the >>> accessibility-platform architecture, make the properties available to the >>> accessibility-platform architecture >>> UX: (MD-7) Ensure that programmatic exchanges between APIs proceed at a >>> rate such that users do not perceive a delay. (UAAG 2.0 2.1.7). >>> UX: (SL-3) Support the display of sign-language video either as >>> picture-in-picture or alpha-blended overlay, as parallel video, or as the >>> main video with the original video as picture-in-picture or alpha-blended >>> overlay. >>> UX: (SL-5) Support the interactive activation/deactivation of a >>> sign-language track by the user. >>> UX: (T-2) Support the provisioning of both scrolling and static display of >>> a full text transcript with the media resource, e.g. in a area next to the >>> video or underneath the video, which is also AT accessible. >>> UX: (TSM-1) The user can adjust the playback rate of the time-based media >>> tracks to between 50% and 250% of real time. >>> UX: (TSM-2) Speech whose playback rate has been adjusted by the user >>> maintains pitch in order to limit degradation of the speech quality. >>> UX: (TSM-3) All provided alternative media tracks remain synchronized >>> across this required range of playback rates. >>> UX: (TSM-4) The user agent provides a function that resets the playback >>> rate to normal (100%). >>> UX: (TSM-5) The user can stop, pause, and resume rendered audio and >>> animation content (including video and animated images) that last three or >>> more seconds at their default playback rate. >>> UX: (TVD-1) Support presentation of text video descriptions through a >>> screen reader or braille device, with playback speed control and voice >>> control and synchronisation points with the video. >>> UX: (TVD-2) TVDs need to be provided in a format that contains the >>> following information: (A) start time, text per description cue (the >>> duration is determined dynamically, though an end time could provide a cut >>> point) >>> UX: (TVD-3) Where possible, provide a text or separate audio track >>> privately to those that need it in a mixed-viewing situation, e.g., through >>> headphones. >>> UX: (TVD-4) Where possible, provide options for authors and users to deal >>> with the overflow case: continue reading, stop reading, and pause the video. >>> (One solution from a user's point of view may be to pause the video and >>> finish reading the TVD, for example.) User preference should override >>> authored option. >>> UX: (TVD-5) Support the control over speech-synthesis playback speed, >>> volume and voice, and provide synchronisation points with the video. >>> UX: (VP-1) It must be possible to deal with three different cases for the >>> relation between the viewport size, the position of media and of alternative >>> content: >>> UX: (VP-2) The user can change the following characteristics of visually >>> rendered text content, overriding those specified by the author or >>> user-agent defaults >>> UX: (VP-3) Provide the user with the ability to adjust the size of the >>> time-based media up to the full height or width of the containing viewport, >>> with the ability to preserve aspect ratio and to adjust the size of the >>> playback viewport to avoid cropping, within the scaling limitations imposed >>> by the media itself. >>> UX: (VP-4) Provide the user with the ability to control the contrast and >>> brightness of the content within the playback viewport. >>> UX: (VP-5) Captions and subtitles traditionally occupy the lower third of >>> the video, where also controls are also usually rendered. >>> UX: [In that this is a user agent issue] (MD-1) Support a >>> platform-accessibility architecture relevant to the operating environment. >>> (UAAG 2.0 2.1.1) >>> UX: (CA-4) Support pre-emphasis filters, pitch-shifting, and other >>> audio-processing algorithms. >>> UX: (DV-5) Allow the author to independently adjust the volumes of the >>> audio description and original soundtracks. [Actually a requirement on the >>> media format] >>> >>> >>> >>> >> >> >> >
Received on Friday, 5 November 2010 09:28:09 UTC