Alt-text not working in pdf.

First, the mouse-on tooltip is an unreliable way to test for alt. text. On some vector graphics, for example, it's not uncommon to tag one of the path elements with a tag (and alt. text) and leave the other elements as artifacts. This would cause the tool-tip to appear only when the mouse-on occurs over the tagged element.

One of the (few) virtues of the Accessibility Checker is the fact that it does, in fact, test your images for alt. text. You can rely on its results in that regard, at least.

Some our images may well be vector graphics, others are not. Here's another part of this.

We have two versions of this document. One is the full 438 page document, the other is component files of the larger version. We needed to have both versions on our website, and I had no urge to do this twice, so I worked on the smaller files, then compiled them into the larger version.

In the larger version there are images where the mouse-over test works, some where it doesn't. There are some images that don't work in either version (may be vector based), some that work in the component files but not in the larger version.

When I added the alt-text info, there were times when only part of the image would highlight (always the upper half), so I can understand that perhaps the whole image did not get tagged. But since it was the upper half, I figured that was the most likely area for the mouse to touch when somone is looking at the file. But that area does not react to the mouse-over either.

One other part - If I open the file in Acrobat, and go into the Touchup Reading Order, it shows the alt-text is in place for all the images. And when I use the Read Out Loud function in adobe, it reads the alt-text correctly.

Since the alt-text is made for readers, it seems to me that it being readable by a reader is really what we need to achieve, and that the mouse-over function isn't all that important. But I am getting some push from higher-ups that the mouse-over is the important function, and that the Read Out Loud is not a sufficient test.

Hi gaidheal,

The mouse-over is insignificant [b]"eye-candy"[/b].

I get to process a rather large population of PDFs that are CAD output.
I've not done a rigorous bean count, shake 'n bake, sort of statistical analysis -- no time for it.
However, it appears that once the PDF page size goes past tabloid the "tool tip" becomes problematic.
This happens with both raster (image) and vector graphic content.
As Duff pointed out, Full Checker (Adobe PDF) will alert you if a element's Alternate Text is missing.Remember, the Alternate Text is for the user of Assitive Technology (aka 'screen readers' - JAWS, Windows Eyes, NVDIA, etc).
The tool tip is, effectively, meaningless to one with a visual impairment (VI) or blind.
A VI individual could be someone with low to moderate visual acuity, [i]after[/i] use of corrective lenses.
To simulate such a condition - get a knee high from your wife/girl friend/the store.
Black is best. A 'skin tone' will do.
Rig up something that will let you place the stretched material over your eyes.
You have an official USN Submarine Service "Vision Obscuring Device" (VOD).
Used to cover the faceplate of EABs/OBAs prior to compartment entry during fire drills.
(simulates a smoke filled space nicely)

Now, find some Alt Text that appears in a 'tool tip' of a PDF. Whip up something from any jpeg/gif/png file it need be.
Slip on your VOD.

Rather awkward to read a 'tool tip' as the text is [i]small[/i].
And, what about the remainder of the PDF page content?
So, the VOD provides a handy litmus test as to the true "value" of a 'tool tip' to one with VI or blind, no?

Those of us who are not VI, let alone blind, do like our 'eye candy'; but, much of it becomes meaningless with the VOD in place.
"Well, just magnify it."
Magnifing content (PDF, paper, whatever) is limited; and this variable has a limit that approaches zero value rather quickly for many.


Here is an extract from an Adobe document on accessible PDF.

Note, no mention of 'tool tip' .Just a closing observation.
When you live with a "VOD" 24/7 it helps if what you need has an organized pattern to support usability and has accessibility that is appropriate to your needs.
Not someone else's notions.

Be well...

I agree with everything you said about a 'tool tip' being meaningless. But, as I said, I'm not the one making the decisions here. So I have to try to find, if not a resolutions, at least an explanation. The tabloid size limitation seems to fit, since it is mostly the auto-cad drawings that are the issue.
With an exception.
In the past, we would get large files that I would split into smaller files for easier access via the web. I would add tags to the full file, alt-text the images, then split into the smaller files ( we also post the full size). The alt-text tags worked ok on the extracted files. But in this case I compiled the smaller files into a full size doc. In the full size no 'tool-tip's are working. Is there information that is not carried into the larger doc that is kept when a tagged doc is split? (I know, I know, the tool-tip isn't important, but it's not my call). The alt-text tags are there, just don't show, where they do on the smaller files.

Actually, I kinda like it when the tool-tip appears.
"My" CAD figures come with a caption that reflects what is in the title block.
Under it's own tag so it gets picked up.
The Alt Text for the element permits providing amplifing information.
I particlarly like this for scanned images of legacy materials such as graphs.
It provides a means of x & y axis and plot description.Not sure what constitutes the "large" files.
A multi-page PDF?
Or a single page "large" PDF (i.e., something like a 44 x 34)?
If the latter, then are you printng, via Adobe Printer, to a smaller page size to achieve a "split"?

Onto Alt Text.
It is a component of the structure tree.
Elements (tags) and components like Alternate Text reside there.
If you have a multipage PDF that is tagged and extract a page the
entire structure tree of the source PDF is replicated in the extracted page.
So, one page with a structure tree for a many page PDF which can be awkward.

Individual, tagged PDFs can be combined such that their structure trees come together in the output PDF.
Use the Option button to alert Combine to do accessibility.

While you can insert a page before or after a page in a PDF; the inserted page's structure tree is
always appended to the end of the existing structure tree.
So, page insert does need to be done in a manner that acknowledges this.

Thing is that when split/page extract and combine/page insert occurs with tagged PDFs
the strucure tree can be made unusable to Assitive Technology applications if the processes
used do not support structure tree integrity (as described in ISO 32000-1).
So, the question to resolve is are those tool-tips attached to a healthy structure tree or to one with dutch elm diesease?

Why bring this up?
A recent post to the webaim listserve provided links associated with testimony
to a judiciary committee of the US Congress.
The transcript of S.R. Bagenstos's testimony makes an interesting read.
S.R. Bagenstos is the Principal Deputy Assistand Attorney General for Civil Rights at the Department of Justice.

It seems calling something Section 508 accessible that is not actually usable by the "end-user" may have gotten a number of organizations in a pickle.

Given that people and organizations have a lot on their plate the execution of good intent sometimes goes awry.
If such should happen when the intention is to provide accessible PDF one might decide to back away from the task.
We all lose should that happen.

Here's a reference link to what John Foliot put to the web.
[url]http://john.foliot.ca/unauthorized/samuelbagenstos.php[/url]
Upper right of web page has link the the fedgov site with a PDF containing "official" transcript.
Links below that go to related testimony.

Be well...

Ok, I wasn't using the combine function before, just inserting files in the correct order. This time I used the combine function and the option for accessibility. So the larger file is created again, the tags are there as they were before, but the alt-text too-tip still doesn't show. In the individual files most of the images show the alt-text tool-tip, but not for some of the autocad images.
If I create a package of the files, the alt-text that displays in the smaller files show in the larger, but again some of the autocad images won't show the tool-tip.

The main issue is still getting those tool-tips to show. Is there a size or complexity limit that won't allow it to display?

I'm also trying to get a tool tip to show the alt text when mousing over figures in PDF. Client is requiring this.

Thought I had it figured out yesterday. Figures initially were metafiles in Word, so I replaced them with bitmaps and generated new PDF, tagged them as "Figure" and specified alt text in tag properties, and the alt text did show up like a tool tip when I ran my mouse cursor over them.

Today, same PDF file, no changes, but tool tip doesn't show up when I run mouse over any of the figures!

Is there a reliable way to get a tool tip to show up? Doesn't necessarily have to be the alt text if there's another way to enter it, but the end result does have to be 508 compliant.

Tried rebooting. Tool tips showing up now. How about that.

My experience with Adobe X Pro has been that if, say, a frame around a figure has alt text but the figure does not, the Accessibility Checker will return a problem with the figure even though screen reader testing confirms the alt text is there. In other words, the checker looks for the alt text attached to the figure and if it does not find it returns a problem even though the document is in fact accessible.

Another question, is it true or not that Screen Tips attached to links and alt text attached to tables in Word 2010 convert to similar items in Adobe X Pro or not? We were told that they do but I have not been able to get that result. Thankxs.