[Blindmath] What does "support braille math in a screenreader" mean technically?

[Susan Jolly]

Despite the Nemeth code having been a US standard for something like 40 
years, there is no transcribing software that can currently convert print 
math fully accurately to Nemeth.  (By print math I mean electronic math 
represented as either LaTeX or presentation MathML.) This problem persists 
despite there having been a significant amount of work addressing this 
issue. The same is true for other math codes but since I know more details 
about Nemeth I will stick mainly to that code here. So it seems to me that 
it is more than a bit unlikely that screenreader developers would have the 
resources to accomplish something that many others have not succeeded at.

I know there is currently a French project attempting to put support for 
several math codes, including Nemeth, into OpenOffice.  I don't know how 
that is progressing.

Please remember that the Nemeth code is a complete code; it has rules for 
both text and math.  The rules for text are quite similar to the rules for 
EBAE (English Braille American Edition) but have minor changes as necessary 
for compatibility with the representation of math.  The reason this fact is 
significant to this discussion is that it is my understanding that 
screenreaders or display drivers that convert to braille text in real time 
use the EBAE rules for text, not the Nemeth rules.

Officially here in the US, materials transcribed according to the Nemeth 
code must consistently follow all the rules of that code.  However, my guess 
is that many Nemeth readers would be quite happy if the text portions of an 
HTML document were to be transcribed according to EBAE while MathML islands 
were transcribed  according to the Nemeth rules for math.  I just noticed 
that the latest version of DBT (Duxbury's software) has something similar in 
that it allows for Nemeth math to be used with various non-English choices 
for text.

There are others on this list who understand the details of MathType and of 
screenreaders so this next may be a bit simplistic.  But it seems to me that 
the minimum you'd want is for a screenreader to simply recognize MathML 
islands and to at least have the capability to pass their contents through a 
user-supplied filter on the way to the display.

Finally let me point out that there are some serious formatting issues to be 
addressed when targetting braille math to a braille display. I'm referring 
to both simple issues such as where to break a line and more complex issues 
involving planar layouts.

I'm hoping for feedback here.

SusanJ