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Re: Do fonts have to be embedded in a WCAG2.0conformingPDFdocument?

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From: Olaf Drümmer
Date: Apr 15, 2015 4:45PM

OK, looking at the Western world / Roman languages (and putting accessibility considerations for people using other scripts to the side for a moment):

Problems one could encounter when looking at visually presented PDFs for which some of all of the fonts are not embedded:
- character spacing 'off'
- e.g. boundaries (per space character) between words disappear, or appear where there are none
- characters move into each other / overlap each other
- justification 'off', fully justified text looks weird
- in cases where the fonts used are sub-standard, or not enough information can be figured out by a PDF viewer to do a decent simulation
- nothing is rendered for such text
- place holder characters are rendered for such text (e.g. bullet characters, or empty squares/rectangles, or … )
- select characters are included by some symbolic font (not uncommon for e.g. currency signs like the infamous Euro sign)
- important details are not rendered or rendered with a useless substitute presentation, might apply to currency sign, trademark sign, measurements units, sub/superscript characters (like for square or cubic meters), mathematical characters, characters representing check boxes or check marks, etc.
- when attempting to print such documents
- printer may fail to output pages where fonts are missing in a PDF, or will use Courier which is difficult to read for just about everyone but much harder for let's say people with cognitive impairments

I am probably forgetting a few aspects here…

While one could argue that a substantial portion of these are usability issues, they can be a much tougher obstacle for people with disabilities. In a way along the same lines as let's contrast: it's hard to read light grey text on white background for just about everyone, but WCAGs bothers anyway to require a minimal contrast for content to be considered visually accessible. I'd argue the same applies to fonts… (i.e. they must be available in their original form, which - for PDF - can only be achieved reliably by embedding them). Anyway - no reason to become nervous because of this aspect - PDF/UA has it covered nicely, and (in this regard as much as in lots of other regards) complements WCAG2 by filling the PDF specific gaps that stopped us from being as efficient as we could have been had authoritative and extensive PDF specific rules and guidelines been available earlier on.

Olaf


PS: BTW - I get reminded of font embedding issues each month when I receive my credit card statement. The character spacing is completely off in the PDF viewer I use. For a word like "hotel" the 'o' and the 't' would move into each other, and the word just becomes difficult to decipher. And it's happening because the font is not embedded and also is not a standard font like Helvetica or Arial that could easily be simulated/substituted by a similar font.



On 15 Apr 2015, at 23:17, Andrew Kirkpatrick < <EMAIL REMOVED> > wrote:

> Yes, France is still in the western world! :) that's part of the point of my scenario.
>
> Given that - what accessibility issues would you expect in that scenario?