How does NVDA recignize table header from untagged pdf


Jonathan COHN
 

Hello,
First, I am assuming you mean that the PDF is tagged, but that the headers are not. I would expect that Column 1 and Row 1 are being considered as headings if no specific header is defined. However
 realize, that PDF can be interpreted by more than just Adobe Reader these days, so, it could even be that the reader you are using puts in implied headers. 
Jonathan
 

On Jul 14, 2021, at 08:49, harsh@... wrote:

I had a doubt regarding table headers, How does NVDA know the table headers of complex tables if they are not defined in pdf structure.

For structured pdf, tags aid for recognizing the headers, but even when they aren't present, NVDA correctly picked headers!!
 
Any explanation on how parsing or code works is welcome