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Re: How to make accessible flowcharts?

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From: Philip Kiff
Date: Feb 8, 2019 9:18AM

I've found all these ideas for alternative formatting of flowcharts and
links to suggestions for text rewriting to be very interesting and
thought-provoking. Thanks!

Circling back to Itzel McClaren's original question of what to do with a
flowchart in a pre-existing PDF, though, I would note that most of these
options are not available. Within a pre-existing PDF that you are trying
to remediate, you are more or less limited to two options:

1. Tag the entire flowchart as one large figure and then add a single
extended description as alternative text.

2. Tag each individual text and graphic object within the flowchart and
then laboriously try to re-order all the elements into a nested list
structure, applying explanatory alternative text onto each specific
shape or connector as you go.

The problem I find with using extended alternative text passages in
option 1 is that you can't add semantic structure to alternative text in
a PDF (it's the same in HTML). So even if you come up with a method of
re-writing the flowchart into a coherent nested list structure, your
alternative text will read as a single stream of text without any list
items or nesting. You can improve things somewhat by creating a
numbering scheme and explaining how that works at the beginning of your
long alternative text stream. But unless you can actually insert the
structured text into the main body of the PDF text where it can be
tagged with regular text structures, then it loses some of its ability
to serve as truly accessible "alternative" text for a flowchart.

I have a few times inserted "invisible" text into PDFs in order to
insert structured semantic text into a pre-existing PDF and make that
text available only to screen readers. By "invisible" I just mean that I
insert the text in the same colour as the background colour of the page,
so it does not appear on screen or in print. But I see that also as an
inadequate method of dealing with complex figures because not all users
who benefit from such explanatory text will be screen reader users.

The best method I've found (aside from editing the source PDF content
and starting over) is option 2, which I think is still not really
adequate except in the case of flowcharts whose object containers in the
PDF can be shoe-horned into a nested list structure.

Phil.

Philip Kiff
D4K Communications

On 2019-02-05 2:19 PM, Itzel McClaren (US - IFS) wrote:
> Hello, we have a flowchart in PDF and we are having a hard time figuring
> out what's the most efficient and effective way to make the flowchart
> accessible. Any suggestions?