PDF UA - Auto-tag API and Accessibility Checker

[Aftia_Jeff]

I have some questions about PDF UA and the Auto-tag API / Accessibility checker.

1.  Does the Auto-tag API set the PDF UA document property (in any situation)?
2.  Do any of the Acrobat Services APIs set the PDF UA document property?
3.  Is there any connection between the PDF UA document property and the actual accessibility of the PDF or is it just a flag to indicate the document should be accessible?
4.  Does the Accessibility Checker report on whether the document is PDF UA compliant? AFAICT, it doesn't.

Thanks,

Jeff

[Joel Geraci · Accepted solution]

Copying the questions to put the responses inline.

Does the Auto-tag API set the PDF UA document property (in any situation)?

No. PDF/UA requires human verification for about 1/3 of the criteria. Because of this, we won't set the metadata automatically.

Do any of the Acrobat Services APIs set the PDF UA document property?

No.

Is there any connection between the PDF UA document property and the actual accessibility of the PDF or is it just a flag to indicate the document should be accessible?

It's just a piece of metadata. See image below. The author is responsible for it being an accurate representation of the level of tagging in the file.

Does the Accessibility Checker report on whether the document is PDF UA compliant? AFAICT, it doesn't.

It reports which machine-verifiable criteria pass, which fail, and what needs to be human verified.  

[Aftia_Jeff]

Thanks Joel.  Is there a comprehensive list of what is machine verified through Auto-tag and Accessibility checker?  Understanding the delta would really help.

[Joel Geraci]

Adobe uses the rules in the Matterhorn Protocol. The protocol consists of 31 checkpoints and 136 failure conditions that identify ways a PDF can fail to meet accessibility standards. 89 conditions can be validated by software tools and 47 conditions require manual review by humans due to their subjective nature. For each check point in the protocol document, the "How" column indicates M or H. M for machine, H for human.