RE: Mathematics as Images

According to the definitions in WCAG, text is "sequence of characters that can be programmatically determined, where the sequence is expressing something in human language".

And human language is "language that is spoken, written or signed (through visual or tactile means) to communicate with humans".

https://www.w3.org/TR/WCAG21/#dfn-text

https://www.w3.org/TR/WCAG21/#dfn-human-language-s


Based on those definitions, I would say there is a very strong case that formulae are text and that images of formulae violate SC 1.4.5 Images of Text.

However, that is only a standards-based view. In practice, images of formulae might be a good solution, but I have no expertise in that area.

Steve Green
Managing Director
Test Partners Ltd


-----Original Message-----
From: Patrick H. Lauke <redux@splintered.co.uk> 
Sent: Thursday, July 20, 2023 11:07 PM
To: w3c-wai-ig@w3.org
Subject: Re: Mathematics as Images

Unless I'm missing something, there's nothing in 1.4.10 Reflow that says that it *doesn't* apply to formulae. I'll note though that the way
1.4.10 is specified, it wouldn't violate 1.4.10 in general if content simply rescales/gets super tiny, as long as it doesn't get cut off or causes bidirectional scrolling. That's unfortunately the way that 1.4.10 was specified.

If the formula simply gets smaller and smaller to fit horizontally into the viewport, then that would normally be a failure of 1.4.4 Resize Text, except that "images of text" are exempt from this criterion.

So then we land on what was, if I recall, the original question: if a formula is presented as an image, does it fail 1.4.5 Images of Text. 
Because if it *does*, then it should be turned into actual text, which then in turn must be resizable under 1.4.4 Resize Text.

However, because support for complex mathematical formulae in browsers has historically been bad to non-existent (with only recent advances in MathML support), the argument that a complex formula must not be presented as an image is currently quite weak - at least in my view.

P

On 20/07/2023 22:13, Wayne Dick wrote:
> Many people did not consider my issue with mathematics as images. This 
> image is a "reflowable" book on Projective Geometry from 
> Springer-Verlag sold on Vital Source. All the text enlarges and 
> reflows, but the mathematical notation  is  not enlarged.
> That is the kind of sloppy presentation of mathematics. It is very 
> hard to read this because you cannot treat it like PDF that you must 
> have to zoom, and you  cannot treat  it like reflowable  text because 
> every formula must be zoomed.
> Vital Source is a web based service. This format is misleading and 
> very difficult to use. It should violate SC 1.4.10. As far as 
> understanding that mathematics is language not images, Springer-Verlag 
> and Vital Source should know  better.
> How can a young person with low vision become a scientist?
> Best, Wayne

--
Patrick H. Lauke

https://www.splintered.co.uk/ | https://github.com/patrickhlauke https://flickr.com/photos/redux/ | https://www.deviantart.com/redux https://mastodon.social/@patrick_h_lauke | skype: patrick_h_lauke

Received on Thursday, 20 July 2023 22:35:28 UTC