Use accessibility tags embedded in PDF

[yurydelendik]

Per conversation with Marco Zehe:

If a PDF file has accessibility tags embedded, such as for headings, tables, form fields, graphics with alternative text etc., try to use them in the text layer

[RyanEdwardHall]

I would really like to see something happen here, we have a blind user at work that took a look at pdf.js output and said it's unreadable with NVDA or JAWS. I understand this a huge challenge given how the div's have to be positioned for text selection, but as the issue stands, visually impaired users are unable to use the library because the dom lacks semantic features

[trjohnst]

Our team is also looking for a very similar feature. It would be great if such a thing was baked into PDF.js to handle semantic markup such as headings, lists, tables, and image. I know PDF's have such information encoded in their file format, but am unsure of the specifics of if they can be translated to semantic markup.

@RyanEdwardHall if the elements contained within the text layer have appropriate resetting applied to them via CSS, would that alleviate concerns around the positioning of the DOM elements?

[somascope]

I too would like such a feature for document structure tagging for accessible PDFs. If it's of helpful reference, these is Adobe's Acrobat page for doing this in software, which possible provides some insight.

[cuhaller]

I've also been looking for a solution to this for a while now and came across this article, https://engineering.linkedin.com/blog/2019/04/under-the-hood--learning-with-documents, outlining how LinkedIn solved this issue using PDF.js for the PDFs uploaded to LinkedIn Learning. I contacted the authors to learn more and they initially seemed open to contribute their edits back, but I haven't heard back after following up and offering to pay for their efforts. Guess they got busy with other projects.

[trjohnst]

@cuhaller that was the very project I was working on that needed accessible tagging. The PDF format when created correctly is surprisingly close to basic HTML elements that aid page readers. I've since left so, unfortunately, do not have access to any of the code. I will check in with the dev that worked on that component.

[cuhaller]

@trjohnst thanks, much appreciated, let us know what you find out.

[jcsteh]

This issue and #6269 are duplicates. I'd suggest this should be closed as a duplicate of #6269, as the latter has more technical details.