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Re: How to make accessible flowcharts?


From: Isabel Holdsworth
Date: Feb 19, 2019 2:38AM

Please everyone avoid adding long and complex strings of alternative
text to images like the plague. Depending on the screenreader being
used, it's not always possible to read the alternative text in a
granular fashion, so it must be read in a single hit. Also, as
mentioned before, many users who could benefit from having complex
images explained won't be screenreader users, but won't have access to
your description.
Cheers, Isabel

On 08/02/2019, Philip Kiff < <EMAIL REMOVED> > wrote:
> 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?
> > > > >