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Re: tagging PDF's

for

From: Duff Johnson
Date: Mar 22, 2012 9:57AM

This issue is one of my bugbears, as some of you know all too well.

On Mar 22, 2012, at 9:41 AM, Bevi Chagnon wrote:

> Karen wrote: "While it is preferable to have both the Tags Panel and the
> Order Panel match up, adaptive technology reads through the Tags Tree so
> making sure it is correct is the goal."
>
> I've come across some AT (other than screen readers) that do use the PDF's
> Reading Order but I can't recall which ones off the top of my head.

So-called AT which uses "reading order" (better understood as: "painting order" for reasons that I will be only too happy to explain again should it be necessary) is relying on LUCK, no more, no less.

Further, so-called AT depending on "reading order" is incapable (in principle, not just in practice) of representing semantic structures such as lists and tables.

Consequently, there is no such thing as AT which uses "reading order" in PDF unless you are also willing to consider a plain-text viewer as an AT for web-pages.

A car will open a can of beans if you drive over the can _just_ right, but (a) it will always make a mess and (b) this capability does not mean that a car is a can-opener.

Likewise, with Acrobat Reflow we have software that offers a few people some (very limited) success some (very limited) amount of the time. That does not make it AT.

> Keep in mind that Acrobat's Reflow utility is one that follows the Reading
> Order, sort of. Reflow doesn't follow Reading Order precisely, but there is
> a definite correlation for most of the items on a PDF's page. I've learned
> that Reflow is being taught to low-vision users so that they can more easily
> enlarge text and navigate through a multi-column PDF.

Acrobat's Reflow is a curse in no small part because it so RADICALLY muddied the waters for users while being just (barely) useful enough to be plausible from time-to-time (basically, as a function of the simplicity of the document) that some have learned to live with it, regardless of how poor an implementation it really is.

> Dana, in InDesign, you can control the PDF's RO through the Articles and
> Layers panels. The sequence in the Articles panel is top down, that is the
> top most item will be read first in the PDF's RO. In the Layers panel, it's
> the opposite: the bottom most item will be read first in the PDF's RO.
>
> So put the 2 panels side-by-side on your monitor and try to get them to
> match up, top down and bottom up. It won't be perfect because the Layers
> panel will have more items in it than the Articles panel, but get as close
> as you can.

How fantastically embarrassing that InDesign is still so poor at PDF production! How many years has it been since tagged PDF was released?

> One suggestion: minimize the number of layers used in InDesign to make it
> easier to rearrange the order of layout items. INDD is not Photoshop and
> most layouts don't need layers to create the visual design, but many
> designers have gotten into the habit of using them unnecessarily.

…that, and tell Adobe to fix ID already!

Duff.