- From: Janina Sajka <janina@rednote.net>
- Date: Tue, 13 Jul 2010 23:51:55 -0400
- To: HTML Accessibility Task Force <public-html-a11y@w3.org>
Colleagues: The following is a first-pass, high level description of the content types and API mechanisms our user requirements expose. It is meant to be a list of things we need to support in our eventual change proposal. it is intentionally agnostic regarding any particular technology. ASSUMPTION: A "default" media content type (video or audio) is presumed in all cases. + 2.1 Audio Description One or more audio tracks Multiple audio tracks may be present to support audio description in various languages, e.g. EN, FR, DE, JP, etc, or to support multiple levels of description. + 2.2 Texted Audio Description Text content with the ability to contain semantic and style instructions. Multiple documents may be present to support texted audio description in various languages, e.g. EN, FR, DE, JP, etc, or to support multiple levels of description. + 2.3 Extended audio description Same as "2.1 Audio Description + 2.4 Clear audio An audio "track." + 2.5 Content Navigation by Content Structure A structured data file. NOTE: Data in this file is used to synchronize all media representations available for a given content publication, i.e. whatever audio, video, and text document--default and alternative--versions may be provided. + 2.6 Captioning Text content with the ability to contain hyperlinks, and semantic and style instructions. QUESTION: Are subtitles separate documents? Or are they combined with captions in a single document, in which case multiple documents may be present to support subtitles and captions in various languages, e.g. EN, FR, DE, JP, etc. + 2.7 Extended Captioning Same as 2.6 Captioning + 2.8 Sign Translation A video "track." Multiple video tracks may be present to support sign translation in various signing languages, e.g. ASL, BSL, NZSL, etc. Note that the example signing languages given here are all translations of English. + 2.9 Transcripts Text content with the ability to contain semantic and style instructions. + 3.1 Access to interactive controls / menus An API providing access to: Stop/Start Pause Fast Forward and Rewind (time based) time-scale modification control volume (for each available audio track) pan location (for each available audio track) pitch-shift control audio filters Next and Previous (structural navigation) Granularity Adjustment Control (Structural Navigation) Viewport content selection, on screen location and sizing control Font selection, foreground/background color, bold, etc configuration/selection Extended descriptions and extended captions configuration/control Ancillary content configuration/control + 3.5 Discovery and activation/deactivation of available alternative content by the user A discovery mechanism and presentation of available media options for user selection. + 3.8 Requirements on the parallel use of alternate content on potentially multiple devices in parallel A discovery mechanism of available OS provided output device options for user selection. -- Janina Sajka, Phone: +1.443.300.2200 sip:janina@asterisk.rednote.net Chair, Open Accessibility janina@a11y.org Linux Foundation http://a11y.org Chair, Protocols & Formats Web Accessibility Initiative http://www.w3.org/wai/pf World Wide Web Consortium (W3C)
Received on Wednesday, 14 July 2010 03:52:26 UTC