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Latest Guideline 1.2 proposal, minor proposed changes to Guideline 1.1

From: Wendy Chisholm <wendy@w3.org>
Date: Wed, 10 Nov 2004 00:10:28 -0500
Message-ID: <4191A2C4.8000200@w3.org>
To: wai-gl <w3c-wai-gl@w3.org>
At the face-to-face I presented a proposal that combined Guideline 1.1 
and Guideline 1.2 [1].  From that discussion,  John Slatin and I took an 
action item to separate the two such that 1.1 focuses on text 
alternatives and 1.2 focuses on synchronized alternatives.  The 
following proposals are the results of these discussions (and also 
available at [2]). While the proposals are not perfect, we hope that 
they are a step forward and may be included in the next drafts for 
public review and discussion.  If adopted, this proposal should close 
the list of 24 issues at the end of this email. 

[1] <http://www.w3.org/2004/10/wcag-media-equiv2.html>
[2] <http://www.w3.org/2004/10/wcag-media-equiv3.html>

Guideline 1.1 Provide text alternatives for non-text content
Level 1

   1. For all non-text content that is functional, such as graphical 
links or buttons, text alternatives identify the purpose or function of 
the non-text content.
   2. For all non-text content that is used to convey information, text 
alternatives convey the same information.
      Note: for multimedia, this means transcripts are provided.
   3. For non-text content that is intended to create a specific sensory 
experience, such as music or visual art, text alternatives identify and 
describe the non-text content.
   4. [deleted]
   5. Non-text content that does not provide information, functionality, 
sensory experience, is marked such that it can be ignored by assistive 
   6. Any text alternatives provided are explicitly associated with 
non-text content.
   7. For live audio-only or live video-only content, such as internet 
radio or webcams, text alternatives describe the purpose of the 
presentation or alternative real-time content is linked to, such as 
traffic reports for a traffic webcam
      Note: real-time content does not imply real-time captions.
      Ednote: This is similar to #1 above, yet it seems we need to 
specifically address  audio-only and video-only content to avoid confusion.

Level 2
Level 3

   1. For multimedia content, a combined transcript of audio 
descriptions and captions is provided.

Example 1: an image used as a button.
A magnifying glass icon is used to link to the search page of a Web 
site. A screen reader identifies the button as a link and speaks the 
text alternative, "Search."

Example 2: a data chart.
A bar chart compares how many widgets were sold in June, July, and 
August. The short label says, "Figure one - Sales in June, July and 
August." The longer description identifies the type of chart, provides a 
high-level summary of the data comparable to that available from the 
chart, and provides the data in a table.

Example 3: a recording of a speech.
The link to an audio clip says, "Chairman's speech to the assembly." A 
link to a text transcript is provided immediately after the link to the 
audio clip.

Example 4: a recording of a symphony.
The link to an audio file says, "Beethoven's 5th Symphony performed by 
the Vienna Philharmonic Orchestra."

Example 5: an animation that illustrates how a car engine works.
An animation shows how a car engine works. There is no audio and the 
animation is part of a tutorial that describes how an engine works. All 
that is needed is a description of the image. From "How car engines 
work: Internal combustion"

Ednote: Examples to be developed: a live radio stream  and a live webcam.

Guideline 1.2 Provide synchronized alternatives for multimedia

Level 1
   1. Captions are provided for prerecorded multimedia.
   2. Audio descriptions are provided for prerecorded multimedia.
   3. If multimedia content is rebroadcast from another medium, the 
accessibility features required by policy for that medium are intact.

Ednote:  Even though there are instances where captions and audio 
descriptions are not required, this version of Guideline 1.2 does not 
attempt to address the variations. Instead, it assumes more detail is 
included in the techniques documents and that policy makers will clarify 
when captions and audio descriptions are required.

Level 2
   1. Real-time captions are provided for live multimedia.

Level 3
   1. Sign language is provided for multimedia
   2. Extended audio descriptions are provided for prerecorded multimedia.
   3. Audio descriptions are provided for live multimedia Ednote: Audio 
descriptions for live multimedia are rare. However, we wanted to 
encourage the development of future techniques.

Example 1: a movie with audio description
Transcript of audio from the first few minutes of, "Teaching Evolution 
Case Studies, Bonnie Chen" (copyright WGBH and Clear Blue Sky 
Productions, Inc.)

Describer: A title, "Teaching Evolution Case Studies. Bonnie Chen." Now, 
a teacher shows photographs.

Bonnie Chen: These are all shot at either the Everglades...for today you 
just happen to be a species of wading bird that has a beak like this."

Describer: wooden tongue depressors

Example 2: a captioned tutorial
A video clip shows how to tie a knot. The captions read, "(music)




 From Sample Transcript Formatting by Whit Anderson

Ednote: Examples to be developed: an animation with soundtrack of music 
with lyrics, an interactive slideshow, an animation with musical soundtrack.

Definitions - to be included in the Glossary:
(didn't finish these)

video-only: @@clarify that it is not a Web page (to address issue 792)

audio description - Additional audio narration that explains important 
details that cannot be understood from the main soundtrack alone. During 
pauses in dialog, audio description provide information about actions, 
characters, scene changes and on-screen text to people who are blind or 
visually impaired.

extended audio descriptions...

captions - A synchronized transcript of dialogue and important sound 
effects. Captions provide access to multimedia for people who are deaf 
or hard of hearing.

multimedia - contains both audio and video

non-text content  - @@

transcript - @@

Summary of issues for this guideline: 

24 Issues that could be closed if this proposal is adopted (some require 
verification from the reviewer before closing):
171, 438, 668, 792, 445, 981, 1084, 446, 447, 477, 667, 793, 871, 980, 
983 (if include suggestions in General Techniques), 1027, 1028, 1029, 
1083, 1085, 1155, 1156, 1157, 1158

9 Issues that are not addressed:  555, 781, 792, 794, 952, 1151, 1152, 
1153, 1154

wendy a chisholm
world wide web consortium
web accessibility initiative
Received on Wednesday, 10 November 2004 05:10:35 UTC

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