Re: Multilingual synthesis

[Tomas Cerha <cerha brailcom org>]

juan rafael fern�ez wrote:
> The scenario:
> ---------------
> A teacher of languages wants TTS in English, Spanish, German, French
> and Italian. Uses Spanish UTF-8 locale.

I believe that such user requirement makes much sense even if you are
not a language teacher.  Many people read and write emails, documents or
browse the web in more than just one language.

As you noted, this is not a problem to use multiple speech engines on
one system and speech APIs, such as Speech Dispatcher support switching
languages on the fly.

The question is, however, how to use this functionality within the user
interface programs, such as screen readers, since most of the time we
don't have the information about the language of the text we are working on.

We must distinguish two distinct areas:
  * User Interface (texts provided by the software in use)
  * The document (or more generally any textual data we work with)

The situation is usually quite good with the user interface.  The
language may be determined from the current locale and a properly
localized system will have all the user interface in just one language.
 Deviations to this rule exist, but I think it is reasonable to consider
them marginal.

Still the best situation in the area of documents is with web documents.
 The language may (and should) be specified in document headers.  We can
also determine the language of each piece of text within the page, which
is good for multi-lingual documents.

The situations with e-mails is notably worse.  As far as I know, there
no language header widely used by current user agents.

I also can't find a way to set a language for a document in
OpenOffice.org, but this may be just my fault.

I believe that the solution to this would be to:
   1. Use the language information wherever possible
   2. Provide a mechanism to switch the language manually

Well, this was all just a theory.  I don't know how is this problem
addresed by screen reader developers, so I would like to join the
question.  What is the current situation and what is the plan?

I am especially interested if Orca currently performs any kind of
language switching and if there is anything I can do to support it in
the Speech Dispatcher backend.

Any comments to this are greatly appreciated!

Best regards, Tomas