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Re: how to detect images having math expressions

for

From: Jukka K. Korpela
Date: Jun 4, 2008 7:40AM


Steve Green wrote:

> It is not helpful to say that an approach should not be considered
> just because it is not 100% reliable.

Did someone say so?

> Nor is it helpful to state that
> sites should be rebuilt or that every page should be tested.

Who said the latter?

I did say that testing could be used to demonstrate that a site should
be rebuilt. The results could prove that it is cheaper to rebuild it
than to fix and patch things.

> The question that we and many other organisations face is how to make
> best use of the available resources.

Don't we all?

> So I would be interested to know how you might approach the task of
> assessing a 10,000 page website with a view to making the most
> beneficial improvements within a budget and timescale that does not
> allow all pages to be assessed.

I wouldn't, except if I were first asked to evaluate the site to see
whether it would, exceptionally, be a candidate for such processing,
given its purpose and orientation and specific accessibility aspects.

It would be waste of time and money to analyze an arbitrary site
according to some large set of evaluation criteria using automatic and
semiautomatic tools. This would just end up with some project that tries
to fix some automatically detectable problems (or "problems" - the tools
tend to detect problems that aren't) if some fixes can be found for
them.

For example, for pages with lots of math expressions (the original topic
of this discussion started), the _real_ accessibility problem is math is
so difficult to most people, and it's even more difficult when presented
poorly. Alt texts are relevant and must be required, but the textual
replacement problem is largely unsolvable in practice. Moreover, the
great majority of people have problems with the math itself. (This
includes, but is not limited to, explaining the meanings of symbols
used.) This shouldn't be difficult to understand (even to a
mathematician), if you just think about it, instead scanning through
endless lists of guidelines and techniques and checkpoints.

Jukka K. Korpela ("Yucca")
http://www.cs.tut.fi/~jkorpela/