Re: [office-accessibility] ODF Accessibility wording for MathML section

[Richard Schwerdtfeger <schwer@us.ibm.com>]

Thank you Steve.

I would suggest rewording of the first paragraph but I understand where you are going with it.

Peter is incorporating your MathML changes into the current draft. Thank you for doing this.


Rich Schwerdtfeger
Distinguished Engineer, SWG Accessibility Architect/Strategist
Chair, IBM Accessibility Architecture Review Board
blog: http://www.ibm.com/developerworks/blogs/page/schwer
"Steve Noble" <steven@dessci.com>

"Steve Noble" <steven@dessci.com>

10/16/2006 11:18 AM

To	Richard Schwerdtfeger/Austin/IBM@IBMUS
cc	<office-accessibility@lists.oasis-open.org>
Subject	[office-accessibility] ODF Accessibility wording for MathML section

Hi Rich,

Here is what we came up with for the MathML language. Also suggesting a
minor rewrite for the opening Section 4 paragraph. Both in the
attachment.

Best regards,

Steve Noble
Director of Accessibility Policy
Design Science, Inc.
E-mail: SteveN@DesSci.com
Phone: (502) 969-3088
(See attached file: odf_math_recommendation.htm)

Title: Recommended language for math in ODF guidelines

Accessibility Guidelines for Implementations of Open Document Format v1.1

Suggested Revisions for MathML Language

4 Converting between ODF and other Document Formats

Accessibility issues surrounding document format conversion are often overlooked. This section covers issues that an office application must conserve to preserve accessibility when converting between ODF documents and other electronic formats such as HTML, DAISY or MS Office documents.

4.5 Preservation of MathML Accessibility Information

MathML is the accepted standard for representing mathematical notation in XML. Accessibility is an important goal of MathML since its inception. It can be used by synthetic speech applications or translated to Braille math codes for use with an embosser to print hard copy Braille or on a refreshable Braille display connected to a computer. MathML supports navigation within a mathematical expression. MathML also provides support for synchronized highlighting of what is spoken for the math, which is an important accessibility consideration both for users with low vision as well as people with print related learning disabilities such as dyslexia. For these reasons, MathML is being incorporated into other accessibility standards, such as DAISY and other ebook and document standards. MathML is also an accepted standard for interoperability between computer applications. Two of the many applications that can accept and/or produce MathML are Microsoft Office 2007 and Mathematica.

MathML can be exported to XHTML for use by Firefox or Internet Explorer when used with the (free) MathPlayer plug-in, which interfaces with screen readers to make the math accessible. MathML is supported in HTML by Internet Explorer and in an experimental version of Firefox, but in general, MathML support in HTML is problematic if cross-platform compatibility is desired. One industry approach to cross-platform compatibility has been to use the object tag in HTML. However, Internet Explorer's implementation of object tag does not follow the W3C guidelines and its rendering results are poor, so this approach is therefore to be discouraged.

An img tag with alt text does provide cross platform compatibility, but at a cost of sacrificing all but the most rudimentary level of accessibility to math. Math images cannot be enlarged well for large print, nor can their colors be changed for those with color disabilities. Math equations supplied in image formats cannot be navigated (other than the description supplied in the alt text), cannot be translated to Braille, nor can synchronized highlighting be supported. It is also important to note that generating good alt text for math is not simple because it must be unambiguous. For example, "1 over n plus 2" can mean "1/n+2" or "1/(n+2)". Furthermore, certain categories of readers may require enhanced verbosity while other may find this more confusing. Although images with alt text might seem like an accessible alternative, their use should be discouraged for the reasons listed above, and MathML should instead be used whenever possible.