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Re: Captions and Alt-text

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From: Chagnon | PubCom
Date: Mar 1, 2013 9:58AM

Unless you are proficient in InDesign, especially with long documents, it is
difficult to see what happens when the PDF is exported from InDesign.
It's entirely based on how InDesign was programmed to convert the pieces
that create the laid out page into structured tags in the PDF. Let me try to
describe what happens.

This is a 300 page book. The body text is one continuous 300-page long
story. A photo and a caption will be on each page, and each one is a
separate computer object.

Therefore each page of the book will hold a portion of the body text story
and its related photo and caption.

InDesign Method #1: Anchored photos and caption boxes.

InDesign has a new tool that lets designers anchor the photo and caption box
into the main body text. The theory is that this tool would drop the correct
figure tag and caption tag where they belong in the main body text tag
structure.
That would be nice if it worked. But it doesn't, not completely. Here is
what you get in the exported PDF:
1. Photo alone = good, creates the figure tag and places it where it
belongs in the structure.
2. Text box alone = broken, creates a gibberish tag that's not
readable.
3. Photo and text together in a box = broken, creates a gibberish
tag.
4. Grouped items = broken, creates a gibberish tag.

InDesign Method #2: Don't anchor the photos and caption boxes.

With this method, the photos and caption boxes are still placed on each page
but are not anchored into the text. They export with the correct tags in the
PDF, but they are ganged at the end of the main story. With this 300 page
book, that means the AT user will see the content in this order:
1. Page 1's body text.
2. Page 2's body text.
Etc. to 300. Page 300's body text.
301. Page 1's figure tag.
302. Page 1's caption tag.
303. Page 2's figure tag.
And so on.

They, by hand in Acrobat, we would move each photo and caption from the end
of the tag structure to where it belongs up front on its related page. Do
that for 300 individual photos and 300 individual captions.

The labor - and cost to the federal government and its taxpayers - is mind
blowing.

Those of you who have had the thrilling experience of moving tags in a PDF
file to correct the tag structure can image how much my team here is looking
forward to this project.

If only Adobe could fix the export of anchored and grouped objects from
InDesign to a tagged PDF we'd be much happier. Gee, all of us taxpayers
would be happier, too!

-Bevi
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- - - - - - - - - - - - - - -
www.PubCom.com - Trainers, Consultants, Designers, Developers.
Print, Web, Acrobat, XML, eBooks, and U.S. Federal Section 508
Accessibility.
New schedule for classes and workshops coming in 2013.

-----Original Message-----
From: <EMAIL REMOVED>
[mailto: <EMAIL REMOVED> ] On Behalf Of Duff Johnson
Sent: Friday, March 01, 2013 10:03 AM
To: WebAIM Discussion List
Subject: Re: [WebAIM] Captions and Alt-text

Bevi,

> But this project was laid out in Adobe InDesign, which has a tragic
> shortcoming: items that are placed inside separate text frames (like
> captions) do not get tagged correctly in the exported PDF, so we end
> up fixing the tags by hand in Acrobat.

One of many many many shortcomings. yes. You'd think that InDesign would do
a good job given that it's developed by the same company that invented PDF,
but...

> Doing this for 300+ photos would be several days' worth of work.
>
> So I'm wondering if this workaround would really work for AT users:
>
> 1) Copy the caption text into the Alt-Text tag, and
>
> 2) Artifact the caption itself so that AT-users don't voice it twice.

This approach isn't great because some kinds of AT won't handle such a
workaround very well - magnifiers (that use tags) won't see the caption, for
example.

Do the captions not follow directly after the photos in the structure tree?
If they do, then why wouldn't your originally proposed approach be
acceptable?

Duff Johnson

Independent Consultant
ISO 32000 Intl. Project Co-Leader, US Chairman ISO 14289 US Chairman PDF
Association Vice-Chairman

+1 617 283 4226
<EMAIL REMOVED>
http://duff-johnson.com

messages to <EMAIL REMOVED>