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Re: Do fonts have to be embedded in a WCAG 2.0 conformingPDFdocument?

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From: Chagnon | PubCom
Date: Apr 15, 2015 9:49AM

Commenting on Duff's response:

Duff: "The lack of embedded fonts can cause a range of issues varying from (merely) an unintended ugly appearance to total illegibility."

True, but if fonts are not embedded in the PDF, Acrobat is designed to substitute default fonts like Times New Roman (serif) and Arial (sans serif). Acrobat used to install with their proprietary default fonts called Adobe Sans and Adobe Sans Serif, but I don't know if that is still the case in the most recent versions of Acrobat.

But, those substituted fonts are scalable (resizable) so their legibility should be ok to meet WCAG. I've never seen a case where the substituted font is a bitmapped font rather than a vector/scalable font; of course, bitmapped fonts aren't resizable. You do miss the aesthetic aspects of the font when, for example, Times New Roman is substituted for a missing handwritten script font. Extremely different appearance, but that's not WCAG.

Duff: "Font embedding is also necessary for Unicode mapping of text, affecting adaptability and reuse, and allowing recovery of semantic properties for each character of the textual content."

Absolutely! And this will continue to become more important as both AT and other publishing technologies start to recognize the difference between, for example, quote mark-like glyphs. In non-Unicode fonts, there's only one symbol to represent open and closed quotes, inches, minutes, and GPS coordinates, so who knows how a screen reader will voice it. But Unicode has specific characters for them which can trigger the appropriate voicing (or interpretation by other technologies). Well, should trigger the appropriate voicing...we're not there yet!

Bottom line:
Use Unicode fonts. Ditch the old TrueType and PostScript fonts.
Check the box to embed them when making PDFs (subset is less than 100% of the characters are used).
And use embeddable fonts. Some fonts are protected, which prevents them from being embedded into PDFs.

--Bevi Chagnon

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Bevi Chagnon | www.PubCom.com
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