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[media] Addressing "2.7 Extended Captioning" feedback

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Thu, 24 Jun 2010 23:03:46 +1000
Message-ID: <AANLkTilb24x-HviA7E2FcucGITw96PBbhdKBJCk3Sfdr@mail.gmail.com>
To: Sean Hayes <Sean.Hayes@microsoft.com>
Cc: HTML Accessibility Task Force <public-html-a11y@w3.org>
Hi Sean,

(cc-ed to a11y TF for documentation)

I'm now reviewing the "extended captioning" section 2.7:

(ECC-1) Much too vague. What are the actual requirements and use cases?

Reply: the use cases are described in the introduction to this
section; however, they should probably be made more concrete and the
term "extended captioning" be described better.

Proposal: add an introductory sentences, something like "Extended
captions are captions that have been enriched with further data -
examples are glossary definitions for acronyms and other intialisms,
foreign terms (for example Latin), jargon or descriptions for other
difficult language. Such extensions can provide important additional
information to the content that will enable or improve the
understanding of the main content to accessibility users. Extended
captioning will be particularly useful for those with restricted
reading skills."

(ECC-2) I would like to see links, but "other activation mechanisms"
is again much too vague. What are the actual requirements and use

Proposal: improve ECC-2 by replacing it with "These enrichments may be
provided as additional timed text tracks, or inline in the captions as
comments, or as hyperlinks on the terms that are being described

(ECC-4) Is the feature part of the format, or a feature of the UA?

Reply: this feature is analogous to extended audio descriptions -
where timing for an extended caption is longer than the available time
for the caption, it may be necessary to halt the media to allow for
more time to read back on the caption and its additional material.

One particular instance of this feature may be: when a hyperlink is
clicked in a caption, the media resource pauses and the new resource
opens in an overlay. When the overlay is closed, the media resource
and the synchronised caption continue.

(ECC-1) What does this mean? What is the format of "metadata markup"?

Reply: see 1. above

(ECC-2) What are "other activation mechanisms"?

Reply: see 2. above

(ECC-4) How does this work? Who decides if "overlap is OK ..."

Reply: if an author provides extended captions, then overlap has to be
expected to play back those captions with the media resource. A user
could always overrule the default behaviour, i.e. decide to ignore
caption extensions, or control them better with from keyboard, etc.

ECC-1,2 and 4 need to be more explicit

Reply: see above

ECC-4	Could say "with the user setting overriding the author setting",
or specify which side sets this option?

Replay: just adopt proosed text

Also I am not sure what ECC-1 and -2 actually mean.

Reply: See 1. and 2. above

(ECC-1), (ECC-2) and (ECC-4) need to be defined more clearly.

Reply: see 1., 2., and 4. above.

Regarding ECC-4 what about providing a feature to configure wrapping
text with smaller fonts? This seems better than cutting off the text.

Reply: it still needs to remain readable, so smaller font is probably
not a good idea.

General, these should probably be called additional text information
or something, as captions are a representation of the audio track; and
this text is not in the audio. This text should not be marked as
caption type.

Reply: The word "caption" is actually menat here, but extended with
further information. And since the effect can be similar to extended
audio descriptions, this seems a valid name for the requirement.

ECC-1 - what user need is this addressing?

Reply: See 1. above

ECC 2 - split into two requirements, one for additional information
that can be displayed in the same time as a caption (Ruby for example
could be considered this kind of information); and another for
information which is presented independantly outside the timeline of
the media.

Reply: don't quite understand what purpose that has

ECC-4 - needs to be distinguished from the normal caption case of two
speech acts that overlap in time (e.g. an interruption).

Reply: are overlapping captions necessary for the "normal case"?

Also the required display time of extended text information is
dependant on the users reading speed. user should have a means to
control the display time and size so that if they can keep up they
avoid pausing the video

Reply: add this as extra requirement

Received on Thursday, 24 June 2010 13:04:41 UTC

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