What libraries are available for analyzing audio files for spoken keywords and/or speech to text?

Question

I'm a super-hero in my off-time and I'm trying to build an application that analyzes audio for spoken keywords. (Think emergency/911 calls) If a keyword is "robbery", and that word is spoken within the audio provided I would like to flag that file and possibly translate it to text.

What development libraries or software applications are out there for doing this sort of thing? C++ or Java libraries are preferred but not required.

Answer 1

Wiki page here is a good starting point. Of the ones mentioned there I think CMU Sphinx is the most active one.

Answer 2

You could work with Praat http://www.fon.hum.uva.nl/praat/ , it's an excelent program for working with phonetics and it has it's own scripting language. You can also find a lot of scripts in the Praat community. You can also use sendpraat http://www.fon.hum.uva.nl/praat/sendpraat.html to work with the praat functions as a subroutine.