[Blindmath] Translating documents with MathML into Nemeth

[Susan Jolly]

Let me make sure we aren't talking apples and oranges here.

There are two ways to translate print to braille, which I'll call realtime 
processing and batch processing.

Realtime processing is used only with braille displays and requires software 
that can translate print electronic documents such as web pages in realtime. 
Screenreaders often have this capability as do some models of braille 
displays. This realtime processing essentially works line-by-line so it does 
not (to my knowledge) produce proper document formatting or handle planar 
layouts.

However, the realtime translators I am aware of only handle narrative or 
literary text. I do not know of any software than can provide realtime 
translation of electronic mathematical expressions (whatever format) to 
Nemeth (or other) braille math.  I'm not sure this would even make sense in 
all situations.

My understanding is that it is the intent of apps like MathPlayer to 
pre-translate math expressions from MathML to Nemeth with the idea that a 
properly configured screenreader could pass this pre-translated braille math 
directly to a braille display while at the same time providing the correct 
realtime translation of any surrounding non-mathematical text.  While this 
would likely be readable, it would not necessarily follow all of the Nemeth 
rules including but not limited to the rules for linebreaking which depend 
on both semantics and the cells per line in the braille display.

Batch processing is used to generate electronic braille documents which are 
treated as paged media where the formatting depends on the specified cells 
per line. The generated electronic braille document can be either displayed 
on a braille display or embossed.  (Of course, if one is reading electronic 
braille on a braille display, it is essential to ensure that this is done in 
translate off mode since it is already translated!) My understanding is that 
there can be problems if one uses a braille display to read an electronic 
braille document that has been formatted for a line length different from 
that of the display but I could be wrong.  I suspect this would be more of a 
problem for mathematical expressions than for text.

So now the question is whether there are batch processors that can translate 
from LaTeX or from HTML+MathML to Nemeth or other braille math codes?  There 
are a number of processors including DBT, TSS, and liblouis which can do 
this to some extent.  However, I don't think there is any current 
translation software that can produce perfect braille math automatically. 
In fact, there isn't any current software that can produce perfect 
contracted American English braille.

I'm getting ahead of myself here but I was going to suggest that the members 
of this list set up some well-designed test input for these applications. 
Good test input is preferably short which means that a lot of separate input 
files are needed to provide complete coverage.

Susan