I used AT & T Natural Voices , which provides JSAPI and MS SAPI bindings. It provides excellent quality voices, a good "general" vocabulary of speech, many pronunciation controls and several languages. It is a bit expensive but works very well.
I used it to read important sensory telemetry for drivers in a mobile sensor application. We had no complaints about voice quality. He had about 75% finished accuracy with scientific terms and much higher (maybe 90% +) with normal dialogue. We got up to 99 +% accuracy using markup (most of the errors were in scientific terms with unusual combinations of phonemes).
It was a bit heavy for the processor (we were working on an equivalent Pentium-III machine, and this gave 50% -75% of the peak processor). It uses a built-in speech engine (compatible with Windows, Linux and Mac) with a Java interface.
There are a huge number of voices and languages ...
James Schek Sep 29 '08 at 19:30 2008-09-29 19:30
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