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Re: PowerPoint accessibility-alt question


From: Chagnon | PubCom
Date: Apr 29, 2014 8:38PM

There is one heck of a lot of misinformation in that online forum thread!
https://discussions.apple.com/thread/2803119 No one seemed to know the
details about fonts.

Summary for the WebAim original poster:

1) Use only OpenType fonts on Macs and Windows.

2) Stop using TrueType and PostScript fonts, both are deprecated font
technologies since 2000. They lack extended character sets which contain
many characters that will help accessibility. Plus, they lack some key
technical requirements for today's publishing technologies, such as EPUBs.
FYI, OpenType fonts can have up to 64,000 characters and are based on a
standardized, universal Unicode character set. That means better
accessibility now, and definitely in the future. Hopefully it will minimize
all those strange characters AT users run into in documents.

3) On the Mac, don't use dFonts as they too present problems in EPUBs and
accessible technologies.

4) Always always always embed your fonts into the PDF. Did I mention always?

5) OpenType fonts come in 2 flavors: TrueType and PostScript. For practical
purposes, this means absolutely nothing. As long as the font is OpenType, it
will be OK to use. The TrueType and PostScript flavors mostly just define
the original source code of the font. Example, Microsoft's fonts were
originally TrueType so their OpenType versions are OpenType/TrueType.
Adobe's font were originally PostScript so their OpenType versions are
OpenType/PostScript. As I said before, this doesn't affect accessibility or
making PDFs. In fact, I haven't seen it affect anything whatsoever except
for producing a lot of hogwash on Internet forums. So use OpenType,
regardless of the flavor.

6) TrueType fonts have the file extension dot TTF. OpenType fonts can have
either dot OTF or dot TTF. Therefore, you can't always tell if you're using
an OpenType font or not. Sighted users can see a blue-green O icon next to
the font name for all OpenType fonts, both TrueType flavored and PostScript
flavored. A blue TT icon appears next to TrueType fonts.

7) Recent operating systems from both Apple and Windows ship with
industry-standard OpenType fonts. Windows also includes a handful of old
TrueType fonts, and Apple ships with a handful of dFonts, neither of which
should be used to make accessible documents or EPUBs. I do not have a good
reason why these 2 companies still ship their operating systems with
out-of-date fonts.

8) The Calibri font mentioned in the forum is part of Microsoft's Cleartype
font collection that were developed specifically for better legibility and
readability on computer screens. They are installed with MS Windows and
Office, so they're fairly well distributed on Windows systems. And they are
in OpenType format.

That was probably more than you ever intended to know about fonts! Being a
former typesetter many decades ago, I couldn't give just a quick

-Bevi Chagnon
- PubCom.com - Trainers, Consultants, Designers, and Developers.
- Print, Web, Acrobat, XML, eBooks, and U.S. Federal Section 508
- 508 Workshop: www.workshop.pubcom.com
- US Federal Training: www.gpo.gov/customers/theinstitute.htm

-----Original Message-----

[mailto: <EMAIL REMOVED> ] On Behalf Of Duff Johnson
Sent: Tuesday, April 29, 2014 5:12 PM
To: WebAIM Discussion List
Subject: Re: [WebAIM] PowerPoint accessibility-alt question

> On the subject of Mac OS conversion of Word/PowerPoint files to PDFs,
we've noticed another problem that is related (I think) to the unicode font
issue - i.e., the PDF rendering wants to use unicode font and if it can't
find a font set that matches the one in the original document, it
substitutes different symbol and letter combinations for some characters in
the resultant PDF. This can make some words unintelligible if you're
listening to the PDF with a screen reader.
> In our experience, it seems to happen most frequently with PDFs that are
created on a Mac. We would love to give instructors and faculty members some
simple instructions on how to avoid this problem - does anyone has any
guidance on which fonts to use and which to avoid when creating MS Office
documents on a Mac?

The issue is: fonts must be embedded when the file is created. This applies
for files created on any platform.

For the Mac, this thread provides some tips to addressing the issue:


I hope this helps.

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