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Guideline 1.2 - Overview and summary

From: Roberto Castaldo <r.castaldo@iol.it>
Date: Sun, 15 Feb 2004 20:06:31 +0100
To: <w3c-wai-gl@w3.org>
Message-ID: <065475718190f24ITNSMTP91@portalis.it>

Overview and summary for Guideline 1.2
--------------------------------------------------


[INTRODUCTION]

From the internal working draft 
(http://www.w3.org/WAI/GL/WCAG20/WD-WCAG20-20031117.html): 
"Provide synchronized media equivalents for time-dependent presentations"

For level 1 there are six success criteria:

Editorial Note: There is discussion about moving some of the current success
criteria from Level 1 to Level 2. The issue stems from trying to apply the
success criteria to every Web cam, newscast, and home broadcast. Another
approach is to allow a conformance claim to state, for example, "All pages
and applications on this site meet the Level 1 guidelines of WCAG 2.0 except
the Web cam at http://example.org/webcam/."

1. an audio descripiton of visual events is provided for audio-visual media.
2. Captions are provided for all significant dialogue and sounds in
time-dependent material.
Editorial Note: A definition for "time dependent" is needed that explains
that it includes audio and visual information presented at the same time, as
well as audio or visual with interaction, or in combination with real-time
events.
Exception: If the Web content is real-time and audio-only and not
time-sensitive and not interactive a transcript or other non-audio
equivalent is sufficient.
Editorial Note: This exception also applies to item 3.
3. descriptions and captions are synchronized with the events they
represent. 
4. if the Web content is real-time video with audio, real-time captions are
provided unless the content:
	a. is a music program that is primarily non-vocal
5. if the Web content is real-time non-interactive video (e.g., a Webcam of
ambient conditions), either provide an equivalent that conforms to guideline
1.1 (e.g., an ongoing update of weather conditions) or link to an equivalent
that conforms to guideline 1.1 (e.g., a link to a weather Web site).
6. if a pure audio or pure video presentation requires a user to respond
interactively at specific times in the presentation, then a
time-synchronized equivalent (audio, visual or text) presentation is
provided. 
Exception: 
if content is rebroadcast from another medium or resource that complies to
broadcast requirements for accessibility (independent of these guidelines),
the rebroadcast satisfies the guideline if it complies with the other
guidelines.


For level 2 there is one success criterion:

Editorial Note: This whole guideline (1.2) needs reworking. Perhaps move
some down from above, or limit the items above to just certain classes of
content - and then put the rest of the coverage (for other types of content)
here.

1. Captions and audio descriptions are provided for all live broadcasts


For level 3 there is one success criterion:

1. The presentation does not require the user to read captions and the
visual presentation simultaneously in order to understand the content


Benefits of Guideline 1.2 (Informative) 

People who are deaf or have a hearing loss can access the auditory
information through the captions.
People who are blind or have low vision as well as those with cognitive
disabilities who have difficulty interpreting visually what is happening
benefit from the audio descriptions of the visual information.
People without disabilities also benefit from the media equivalents.
-People in noisy environments or with muted sound often use captions.
-Captions are used by many to develop language and reading skills.
-Audio descriptions also provide visual information for people who are
temporarily looking away from the video presentation such as when following
an instructional video and looking at their hands.
-Captions and text descriptions can also be used to index and search media
files.

Note: 
Time-dependent presentations requiring people to use a single sense to
follow two or more things at the same time may present significant barriers
to some users. Depending on the nature of the presentation, it may be
possible to avoid scenarios where, for example, a deaf user would be
required to watch an action on the screen and read the captions at the same
time. However, this may not be available for live broadcasts (e.g. a
football game). Where possible (especially for education and training
materials), provide content so that it does not require tracking multiple
simultaneous events with the same sense, or, give the user the ability to
freeze the video so that captions can be read without missing the video.


Examples of Guideline 1.2 (Informative) 

Example 1: a movie clip with audio description and captions. 
A clip from a movie is published on a Web site. In the clip, a child is
trying to lure a puppy to the child's bedroom by laying a trail of crumbs.
The child mumbles inaudibly to himself as he lays the trail. When not
watching the video, it is not obvious that he is laying a trail of crumbs
since all you hear is the mumbling. The audio description that is
interspersed with the child's mumbling says "Charlie lays a crumb on each
stair leading to his room." The caption that appears as he mumbles is,
"[inaudible mumbling]."

Example 2: a video clip of a news story. 
A video clip accompanies a news story about the recent flooding in a major
city. The reporter describes what is seen, for everyone. No audio
description is necessary. The captions display what the reporter is saying.

Example 3: a silent animation. 
An animation shows a pantomime climbing a ladder. There is no audio track
for this animation. No captions or audio description are required. Instead,
a text equivalent is provided as described in guideline 1.1.


[1. OUTSTANDING AND SUMMARY FOR ISSUES]

Here are all the open issues in Bugzilla about this guideline:

. Bug 171: accessible rebroadcasts 
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=171) 
This is about exceptions for rebroadcast of TV signals. Jason White's
Solution: if content is rebroadcast from another medium or resource that
complies to broadcast requirements of accessibility (independent of these
guidelines), the rebroadcast satisfies the checkpoint if complies with the
other guidelines.
. Bug 438: exception for rebroadcast video needs clarification
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=438)
It's about rebroadcast exception, and Jim House writes "Not sure if I
understand this right - what about news websites where they show clips from
previous television broadcasts that were captioned on television but not on
the web.  For example, I would like to see CNN or ABC or FOX caption their
web video clips."
. Bug 445: what does "primarily non-vocal" mean?
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=445)
CKW ask at what point does a music program become "primarily non-vocal"? Is
it possible to caption real-time music programs that have vocals? For
example, Shania Twain performing "live" at half-time of the Super Bowl is
real-time video with audio and is a music program that has vocals. Is it
required to caption the lyrics or is it ok to say, "Shania Twain performs
her song XYZ?"
. Bug 446: Move item 4 from required list (real-time, non-interactive)  to
1.1?
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=446)
CKW write: this guideline (1.2) is about synchronization of equivalents.
Does it make sense to have a criteria about text equivalents that are not
synchronized? Perhaps this fits best in Guideline 1.1?
. Bug 447: clarify item 5 under required?
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=447)
CKW put in evidence his doubts about "if an audio-only or video-only
presentation requires a user to respond interactively at specific times in
the presentation, then a time-synchronized equivalent (audio, visual or
text) presentation is provided" 
. Bug 477: simplify 1.2?
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=477)
Olivier Thereaux writes: "1.2: seems a bit on the verge of technology
independent. Would be nice if the requirements could be simplified and most
of the existing wording could be moved to examples/techniques." 
. Bug 555: Clarify use of captions for music with lyrics
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=555)
The U.S. Access Board writes: ". the Board selected the term multimedia
presentations instead of the term "media".  A single media, such as a video
only event, would require text equivalents.  Describing the output from a
web cam is a difficult issue.  We do agree with the WAI suggestions for
handling web cam output (provide a link to equivalent information in text
when possible).  Also, regarding captioning, clarification is needed on
whether this requires music with lyrics to display the lyrics as captions on
the screen?"
. Bug 597: proposed wording for Guideline 1.2, SC 2
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=597)
Current wording for Checkpoint 1.2, SC 2:
2 . All significant dialogue and sounds are captioned
Exception: if the Web content is real-time and audio-only and not
time-sensitive and not interactive a transcript or other non-audio
equivalent is sufficient.
Editorial Note: This exception also applies to item 3.
Proposed wording for Guideline 1.2, SC 2
2. Captions are provided for all significant dialogue and sounds.
Exception: A text transcript or other non-audio equivalent that is not
synchronized with the multimedia presentation satisfies this success
criterion if all four of the following statements about the content are
true:
(a) The content is real-time and 
(b) the content is audio-only and 
(c) the content is not time-sensitive and 
(d) the content is not interactive.
. Bug 598: proposed wording for Guideline 1.2, SC 3
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=598)
Current wording for Checkpoint 1.2, SC 3:
3. Descriptions and captions are synchronized with the events they
represent.
Exception: If the Web content is real-time and audio-only and not
time-sensitive and not interactive a transcript or other non-audio
equivalent is sufficient.
Proposed wording for Guideline 1.2, SC 3:
3. Descriptions and captions are synchronized with the events they
represent.
Exception: A text transcript or other non-audio equivalent that is not
synchronized with the multimedia presentation satisfies this success
criterion if all four of the following statements about the content are
true: 
(a) The content is real-time and 
(b) the content is audio-only and 
(c) the content is not time-sensitive and 
(d) the content is not interactive
. Bug 599: Proposed wording for Guideline 1.2, SC 4
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=599)
Current wording for Checkpoint 1.2, SC 4:
4. If the Web content is real-time video with audio, real-time captions are
provided unless the content: 
* is a music program that is primarily non-vocal
Proposed wording for Guideline 1.2, SC 4:
4. If the Web content is real-time video with audio, then real-time captions
are provided.
Exception: if the content is a music program that is primarily non-vocal,
then captions are not required.
. Bug 600: Proposed wording for Guideline 1.2, SC 5
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=600)
Current wording for Checkpoint 1.2, SC 5:
5. If the Web content is real-time non-interactive video (e.g., a Webcam of
ambient conditions), either provide an equivalent that conforms to
checkpoint 1.1 (e.g., an ongoing update of weather conditions) or link to an
equivalent that conforms to checkpoint 1.1 (e.g., a link to a weather Web
site).
Proposed wording for Guideline 1.2, SC 5: 
5. If the Web content is real-time, non-interactive video (for example, a
Webcam view of weather), then one of the following is provided: 
* an equivalent that conforms to Guideline 1.1 (for example, an ongoing text
report of weather conditions);
* a link to an equivalent that conforms to Guideline 1.1 (for example, a
link to a weather Web site that conforms to Guideline 1.1).
. Bug 601: Proposed wording for Guideline 1.2, SC 6
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=601)
Current wording for Checkpoint 1.2, SC 6:
6. If a pure audio or pure video presentation requires a user to respond
interactively at specific times in the presentation, then a
time-synchronized equivalent (audio, visual or text) presentation is
provided.
Exception: if content is rebroadcast from another medium or resource that
complies to broadcast requirements for accessibility (independent of these
guidelines), the rebroadcast satisfies the checkpoint if it complies with
the other guidelines.
Proposed wording for Guideline 1.2, SC 6:
6. If a presentation that contains only audio or only video requires users
to respond interactively at specific times during the presentation, then a
synchronized equivalent presentation (audio, visual or text) is provided. 
[js note, 24 October: Is the word "presentation" necessary in
"time-synchronized equivalent presentation"? To me it seems to imply a
different presentation rather than a synchronized equivalent.]
Exception: if content that is rebroadcast from another medium or resource
meets accessibility requirements for that medium, then the rebroadcast
satisfies this guideline if it complies with other applicable sections of
WCAG 2.0.
. Bug 602: Proposed wording for Best Practice Measures for Guideline 1.2
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=602)
Current wording for Best Practice Measures for Checkpoint 1.2:
2. captions and audio descriptions are provided for all live broadcasts.
3. the presentation does not require the user to read captions and the
visual presentation simultaneously in order to understand the content. 
Proposed wording for Best Practice Measures for Guideline 1.2:
2. Synchronized captions and audio descriptions are provided for live
broadcasts.
3. the presentation does not require the user to read captions and follow
the visual presentation simultaneously
. Bug 667: is audio description alone sufficient?
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=667)
This is about audio description, and Greg Lowney writes: "Is an audio
description alone sufficient? It doesn't help a person who is deaf-blind,
who would instead benefit from having a textual description of the visuals,
which in turn could be reformatted into Braille or presented on a Braille
display. If you decide not to require textual descriptions for any
checkpoints, then I recommend at least making and explaining the explicit
decision to do so".
. Bug 668: 1.2 exception needs clarification
(URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=668)
Greg Lowney writes about this exception: "if content is rebroadcast from
another medium or resource that complies to broadcast requirements for
accessibility (independent of these guidelines), the rebroadcast satisfies
the checkpoint if it complies with the other guidelines", and says: "I'm not
sure I understand this exception. Take the example of a news broadcast on
television which is provided with closed captions when broadcast live; if
the live broadcast complies with accessibility guidelines for live
broadcasts, that would seem to invoke this exception and thus mean that the
web site where the broadcast is available for later viewing is not required
to provide any captioning.  Is that your intention?  Is the implication that
Checkpoint 1.1 would still be required, and be satisfied by providing static
rather than synchronized transcripts?  I do not understand why the
requirement should be higher for a multimedia presentation which is only on
the web site that it is for something that is now owned on the web site but
at one time was available somewhere else."


[2. PREVIOUSLY PROPOSED SOLUTIONS]

. Guideline

This isn't about Guideline 1.2 text, but refers to its structure and
content; in [Bug 477] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=477), Olivier Thereaux
asks to simplify the requirements and move most of the actual wording to
examples/techniques.

. Level 1 Success Criteria for guideline 1.2

1) In [Bug 667] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=667), Greg Lowney asks
whether is an audio description alone sufficient, as it is not enough for
deaf-blind persons, who would need a textual description of the visuals.
Anyway, "if you
decide not to require textual descriptions for any checkpoints, then I
recommend at least making and explaining the explicit decision to do so"

2) From [Bug 597] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=597), the proposed
wording for this SC is:
2. Captions are provided for all significant dialogue and sounds.
Exception: A text transcript or other non-audio equivalent that is not
synchronized with the multimedia presentation satisfies this success
criterion if all four of the following statements about the content are
true:
(a) The content is real-time and 
(b) the content is audio-only and 
(c) the content is not time-sensitive and 
(d) the content is not interactive.
3) From [Bug 598] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=598), the proposed
wording for this SC is:

3. descriptions and captions are synchronized with the events they
represent.
Exception: A text transcript or other non-audio equivalent that is not
synchronized with the multimedia presentation satisfies this success
criterion if all four of the following statements about the content are
true: 
(a) The content is real-time and 
(b) the content is audio-only and 
(c) the content is not time-sensitive and 
(d) the content is not interactive.

4) From [Bug 599] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=599), the proposed
wording for this SC is:
4. if the Web content is real-time video with audio, then real-time captions
are provided. Exception: if the content is a music program that is primarily
non-vocal, then captions are not required.
In [Bug 455] (URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=455),
CKW ask "At what point does a music program become "primarily non-vocal?"",
e.g. in music programs which have vocals.
In [Bug 446] (URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=446),
CKW say "Does it make sense to have a criteria about text equivalents that
are not synchronized? Perhaps this fits best in Checkpoint 1.1?"
In [Bug 555] (URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=555),
a clarification is needed on whether is necessary for music with lyrics
programs to display the lyrics as captions on the screen

5) From [Bug 600] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=600), the proposed
wording for this SC is:
5. if the Web content is real-time, non-interactive video (for example, a
Webcam view of weather), then one of the following is provided:
* an equivalent that conforms to Guideline 1.1 (for example, an ongoing text
report of weather conditions);
* a link to an equivalent that conforms to Guideline 1.1 (for example, a
link to a weather Web site that conforms to Guideline 1.1).

6) From [Bug 601] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=601), the proposed
wording for this SC is:
6. if a presentation that contains only audio or only video requires users
to respond interactively at specific times during the presentation, then a
synchronized equivalent presentation (audio, visual or text) is provided. 
[js note, 24 October: Is the word "presentation" necessary in
"time-synchronized equivalent presentation"? To me it seems to imply a
different presentation rather than a synchronized equivalent.] 

Exception: if content that is rebroadcast from another medium or resource
meets accessibility requirements for that medium, then the rebroadcast
satisfies this guideline if it complies with other applicable sections of
WCAG 2.0.
[Bug 438] (URL: http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=438),
from Jim House, is about broadcast exception; he requests to clarifying
about news websites where they show clips from previous television
broadcasts that were captioned on television but not on the web.
Also Greg Lowney, in [Bug 668] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=668), asks for
clarification concerning this exception: "if the live broadcast complies
with accessibility guidelines for live broadcasts, that would seem to invoke
this exception and thus mean that the web site where the broadcast is
available for later viewing is not required to provide any captioning". Is
it really the working group's intention?


. Level 2 Success Criteria for guideline 1.2

1) from [Bug 602] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=602), the word
"Synchronized" has been added, so the proposed wording for this SC is:
2. Synchronized captions and audio descriptions are provided for live
broadcasts


. Level 3 Success Criteria for guideline 1.2

1) From [Bug 602] (URL:
http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=602), the proposed
wording for this SC is:
3. the presentation does not require the user to read captions and follow
the visual presentation simultaneously


. Benefits of Guideline 1.2
[No proposal]

. Examples of Guideline 1.2
[No proposal]



[3. NEW PROPOSED SOLUTIONS]

. Guideline
[No proposal]

. Level 1 Success Criteria for Guideline 1.2
1) I agree with Greg about deaf-blind persons' needs, a text equivalent
should be provided too.
2) [No proposal]
3) [No proposal]
4) This is one of the most controversial point, especially about music with
lyrics which IMHO should always have captions; the problem is in the word
"primarily", which doesn't represent an objective concept. One way of
solving this problem may be to say "completely non-vocal", instead of
"non-vocal", so this criterion would become:
4. if the Web content is real-time video with audio, then real-time captions
are provided. Exception: if the content is a music program that is
completely non-vocal, then captions are not required.
5) [No proposal]
6) [No proposal]

. Level 2 Success Criteria for Guideline 1.2
[No proposal]

. Level 3 Success Criteria for Guideline 1.2
[No proposal]

. Benefits of Guideline 1.2
[No proposal]

. Examples of Guideline 1.2
I'd add an example about music with lyrics, to fix any possible
misunderstanding about 


[4. DEPENDENCIES BETWEEN GUIDELINES]

(1.1) For non-text content, provide text equivalents that serve the same
purpose or convey the same information as the non-text content, except when
the purpose of the non-text content is to create a specific sensory
experience (for example, music and visual art) in which case a text label or
description is sufficient
(3.3) Content is no more complex than is necessary and/or is supplemented
with simpler forms of the content. In particular, Level 2 SC point 1.g:
inclusion of non-text content to supplement text for key pages or sections
of the site where they felt it was appropriate.


[5 . ASSUMPTIONS]

I assume that WCAG working group intends to value multimedia elements on web
pages, and to make them fully fruible from anyone. One of the main
objections people often make about accessibility is that, in their opinion,
an accessible page/site is not as attractive as a "traditional" one; too
many times accessibility guidelines are considered as a heavy limit to web
pages users interaction and experience; they're a great opportunity instead.

With today's fast growing broad band Web connections, images, animations and
audio-video elements tend to gain more and more importance, and after all.
who likes only-text Web sites?
So, this Guideline puts the focus on how a developer can build pages with
multimedia elements and make them accessible at the same time, so that
everybody can understand that even the live SuperBowl final match can be
made accessible for every Web user.


[6. RATIONALE]

This guideline is useful for all Web users, in particular for people with
disabilities. 
Users who are deaf or have hearing loss can get informations by reading them
in the captions, blind people or low- vision people can hear meaningful
descriptions of every significant audio-video element on the Web page; also
people with cognitive disabilities benefit from audio descriptions of the
visual information (everyone after ten working hours becomes a low-vision
or/and a cognitive disable person).
All media equivalent can be very useful for all users, in many different
situations: 
.	Multimedia Web applications run in noisy environments ;
.	Collective e-learning sessions, where all audio elements must have a
proper synchronized caption;
.	Captions can be very useful in many cases to improve language and
reading skills (e.g. foreign language training sessions).



Roberto Castaldo
-----------------------------------
www.Webaccessibile.Org Coordinator
IWA/HWG Member
rcastaldo@webaccessibile.org
r.castaldo@iol.it
Cell 348 37 00 161
Icq 178 709 294
----------------------------------- 
 
Received on Sunday, 15 February 2004 14:06:33 UTC

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