Problem with role mapping paragraph styles to tags, from InDesign to PDF.

[GreenRoof]

I am using InDesign 15.1.1 to create several accessible, tagged PDFs.

I have tagged every paragraph style correctly under the export tags for PDF (Edit all export tags > show: PDF), and I have left any list items and table of contents items with the default ‘Automatic’ tag.

I am exporting as an interactive PDF with ‘Create tagged PDF’ checked. 

Then when viewing the PDF in Acrobat Pro DC, in the Tags pane I have selected ‘Apply role mapping to tags’. This should ensure that in the tags pane in Acrobat, all my original paragraph style names are displaying as the tags that I have created. But this is not happening. I am finding that some of the tags are role mapping correctly, while several other tags are appearing incorrectly role-mapped with their original paragraph style names in place instead of the tags that I had assigned to them in InDesign.

There seems to be no logic to this. Why have some of my paragraph styles been role mapped correctly as per the tags I have created in InDesign and yet some styles have not? I am having to fix the role mapping, tag by tag in Acrobat which is a tortuous waste of time.

Is there a bug that can be causing this? I really need a solution as I have some very large documents to create as accessible PDFs.

[GreenRoof]

Having revisited this same project a year later, to produce an update of the design, the role-mapping problem I first posted about was still occurring. After a year of experience, I can confirm that the way to fix the problem is to simply rename some of the longest or similarly worded paragraph styles to make them simpler and less similar. I rename a few styles at a time and re-export the PDF until it finally role maps correctly.

As a matter of course nowadays I try to avoid too many long paragraph styles which begin with the same wording, such as: 'Body copy front section accounts - bold'; 'Body copy front section accounts - italic'; 'Body copy front section accounts - blue'. Instead I might call them 'Bold body copy front section accounts'; 'Italic body copy front section accounts'; 'Body copy front - blue', just to mix it up a bit. This seems to avoid any problems with the role mapping.

[Bevi Chagnon - PubCom.com · Accepted solution]

Yes, confirming that long InDesign style names often cause conflicts during Acrobat's role mapping.

Although the style name becomes the "custom tag" in Acrobat (the long tag names that are similar to our InDesign style names), they are truncated by the PDF Export / Acrobat utilities. So long InDesign names can become wierdly named or overriden in Acrobat tags.

Easy solution: as you mentioned, write shorter names for your InDesign paragraph styles. Why not use some shorthand:

P = body text

B = bold

Your 'Body copy front section accounts - italic' can become 'P front sec accts - I'.

Added benefit: by starting a style's name with the intended final tag, it's easy to check and correct the role mapping in Acrobat.

[GreenRoof · Accepted solution]

Thanks for the affirmation Bevi.

Yes, I have discovered that when InDesign paragraph style names are long, and begin with the same wording then they can get confused during PDF export. During PDF export only the initial few characters of the style name are used by the software to specify the role mapping, meaning anything that you have placed at the end of a long name to differentiate it from other similarly worded styles may get lost, thereby confusing one style with another. This can either result in incorrect role mapping (i.e the wrong tag being applied) or no role mapping (i.e. the paragraph style name appears in the tags panel instead of the tag specified in InDesign.

If possible, can you vote this as the correct answer for the benefit of others? Then hopefully it won't take them ages to work it out for themselves as I had too! 🙂 Many thanks.

Thanks for the shorthand tips.

[_Aaron_]

What constitutes a too-long style name? In other words, how many characters are allowed before Acrobat truncates it?

[GreenRoof]

In my experience it's 20 characters (including spaces, dashes etc). So if you named two paragraph styles like this:

'main heading big blue' [i.e. 21 characters]

'main heading big blue section 2'

... then they would both be truncated to the same thing, i.e. 'main heading big blu'. This is where the software starts getting confused.

Hope that helps.

As Bevi has suggested, a simple way to avoid this is to add some tag shorthand at the front of the name to differentiate them. For example if you re-named the above as shown below then there would be no confusion if they get truncated:

'h2 main heading big blue'

'h3 main heading big blue section 2'

[_Aaron_]

Thanks for clarifying, GreenRoof!

[Bevi Chagnon - PubCom.com]

Confirming @GreenRoof suggestion.

However, we've had tag problems when two or more InDesign style names are at 20 characters: they all get truncted to the same 20 characters.

So our advice: 19 characters max in any style name.

[Iain McLeod]

I may have found a workaround. 

I have a long document with quite prescriptive tagging, all mapped through the Paragraph Style's Export Tagging and verified through "Edit all Export Tags" – but several styles refuse to tag/role-map properly in an interactive PDF (they are completely missing in the PDF's role map). I've tried a long list of things to fix it, most of which are covered in this thread, but the only thing that works is to:

– create a text frame on the first page that just overlaps the page bounds (so that it doesn't appear on the page but does get included in the tag structure)

– add some sample text and style it with the paragraph styles that go missing (probably better practice to include every style)

– export and check

– delete the dummy text's "<Sect>" tag so that it isn't read by assistive technology

– save.

I only discovered this as I got tired of trying to manually find the styles in Acrobat, the first of which appears 46+ pages into this document, with no way to search in the Tags panel. 

It looks very much like the export to interactive PDF function gives up on building the role map after a number of pages have been exported... this might also explain why some users can get results when exporting a subset of pages.