Dealing With Math and Screenreaders, Part 1

Reading Math Content

In the Previous post, we began exploring the subject of maths accessibility while using a screen reader. In this post, I hope to answer the very first question one might have regarding this important topic: how does one read maths using a screen reader?

In the past, it had been a difficult call to use screen readers to read mathematical content. Nowadays, though, a major screen reader like JAWS comes equipped to deal with maths content, especially if you are running Version 2020.

I will be discussing using NVDA as you will require some addons to deal with it.

Key Terms

When discussing mathematics, (whether as maths or math), it is important to avoid ambiguities. So throughout this post, the following working definitions will be used.1

term

A number, variable or any unit demarcated by an operator. for instance, an expression like $1 +3$, 1 and 3 are terms.

operator

A symbol that is an action of the expression. It tells us what is to be done to get a value. For instance:

OperatorAction
$+$Add
$-$Subtract
$\times$Multiply
$\div$Divide

: Common Maths Operators

Mathematical expression (or “expression” for short)

A set of terms, which when evaluated, give a single value. An expression is seen by its combination of terms along with operators like $+$, $-$, $\times$. For example, this is an expression: $8 + 8$, and this one as well: $$3x^2 + 12x - 9$$

Equation

An expression with an equal sign in it. For example, $1 + 4 = 5$ is an equation because it means whatever is on the lefthand side is equal to whatever is on the righthand side.

Variable

A letter which stands in place of a number. For example, when we say, $x^2$, that $x$ could stand for any number such that if we choose 5 to fill that variable, then the answer would be 25 because $5^2 = 25$.

The Problem

The need to read print material using some form of a computing device such as a computer, smartphone or a tablet by people who are blind is behind the need for screen readers. A screen reader is more than a simple application. It represents a whole environment, more or less like the operating system itself.

Because of that, whenever one thinks of reading any material, his or her first port of call is the screen-reader: will it be able to handle the material one throws at it? With prose,2 there is no problem. However, for a long time, dealing even with a simple mathematical expression like $x^2-x$ was not possible.

The challenge with mathematical expressions has to do with the fact that maths in itself is an expressive language, one that conveys a single meaning in an unambiguous manner as natural language does. Because of that, even in the history of digital text itself, it took a long time for it to be written accurately. For instance, until Professor Knuth developed the TeX language in the mid-70s, some maths symbols could not be accurately represented in digital form.

This makes it understandable why screen readers may not handle maths as one would wish to be productive.

The challenge with maths reading has to do not only with expressions, but tables, matrices, equations and plotting.

We often come across maths in documents, whether PDF or Word, and online.

Solution

If you are using the latest version of JAWS it should be able to read maths content on HTML pages using MathML format.

When using NVDA, a free and Opensource screen-reader, regardless of which version you will be using, you can install the Access8Math Addon.3 With this addon loaded, whenever you come across a math expression,

  • NVDA will change a tone to indicate that it has encountered maths expressions;
  • To interact with the expression,
    1. Press the SPACEBAR or ENTER key.
    2. A dialog box will launch letting you either copy or start the INTERACTION session.
  • When you want to investigate the whole expression, just Press the ENTER key to:
    • Move around the maths expression in a virtual window;
    • NVDA will display all the terms in the expression. Move from one term to another term using the LEFT and RIGHT ARROW keys.
    • You can further explore each term by pressing the DOWN ARROW key. Do this for any sub-term, until you hear “NO MORE zooming” or something to that effect.
    • Press the UP ARROW key to get out of a term.
    • Press the HOME key to navigate to the beginning of the entire expression.
  • After exploring an expression, press the ESCAPE key and close the Access8Math window by ALT+F4.

The advantage with Access8Math is that it can read even displayed maths in matrices and other arrays. You can move between columns and rows in the same way you would when exploring a simple expression.

The MathPlayer

While the above solutions work for HTML pages, we need a solution to deal with maths in Word documents. For that I recommend the free Math Player, which is developed by Design Science who also develop MathType which we will discuss in the next post on writing Maths.

MathPlayer makes it possible to read maths expression in the same way you would do using Access8Math in NVDA. It can also handle both simple and tabular expressions.

The only setback to MathPlayer as of the date of writing is that it seems not to be updated on a regular basis.

The Central Access Reader

While the above solutions may help for those on Windows, they do not work on Mac OS X. Also, It may be difficult to copy the maths expression as it is spoken. While Access8Math lets you copy the expression, it does so in its raw XML form.

To deal with these limitations, you may consider the free Central Access Reader (CAR) developed by the Central Washington University. Unlike MathPlayer, this one is regularly updated.

Central Access Reader is self-voicing, which means it is not specifically targetted to blind people only. It does not need your screen-reader. Instead, it uses the default voices on your computer to read for you. Self-voicing programs are good at that: they often come with not only audio feedback, but you can save that recording to MP3 and play using any music player. Anyway, we will discuss these self-voicing programs in a future post.

Using CAR, you can load your MS Word documents and paste text from the clipboard, and press the PLAY button. The way CAR handles maths is that it is verbose with expressions. When you save content using CAR, it also saves these verbose expressions, telling you when you just entered a numerator, ended a bracket and so forth. In my opinion, this is great especially when you are dealing with complicated formulas which you need to use for hand calculations.

Conclusion

Reading maths is not yet as perfect using screen-readers as we would have liked. However, great strides are being made. In fact, there are ways to not only deal with expressions, but even diagrams and plots. For the sake of space, I could not discuss these options, some of which are commercial, but I promise that I will provide a review of these programs one of these days.

For instance, the LaTeX Access — which is Open Source — and the LAMBDA programs provide a fully accessible solutions for both screen-readers and braille displays.

If you’ve installed some of the programs mentioned here, the best way to test them out and see whether your screen-reader can now handle maths is either

  • Reread this post and see whether you can now hear math expressions correctly;
  • go to this Math Torture site and hear how much you can handle. If your screen-reader can go through all the expressions, then you know that you are good to go. and
  • Best of all, start reading maths content and understand what you didn’t before.

I hope that by now, you have seen that it is possible to read maths and be productive. Until next time, happy reading and calculating!


  1. These terms I defined them this way for simplicity, they are not official. ↩︎

  2. Text used for natural languages like this post you are reading. ↩︎

  3. An addon is a script written for NVDA to perform extra functionality beyond its general screen-reading capabilities. Addons are popular for both NVDA and JAWS screen-readers. ↩︎

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