Pocketsphinx. Here is a demo https://www.youtube.com/watch?v=tfcme7maygw https://www.youtube.com/watch?v=tfcme7maygw and a blog post about how to do it: https

Pocketsphinx. Here is a demo https://www.youtube.com/watch?v=tfcme7maygw https://www.youtube.com/watch?v=tfcme7maygw and a blog post about how to do it: https://scaryreasoner.wordpress.com/2016/05/14/speech-recognition-and-natural-language-processing-in-space-nerds-in-space/ https://scaryreasoner.wordpress.com/2016/05/14/speech-recogn... Code is in here (gpl2) https://github.com/smcameron/space-nerds-in-space https://github.com/smcameron/space-nerds-in-space In particular, look at snis_nl.h, snis_nl.c The trick with pocketsphinx is to limit the vocabulary you want to recognize, and create a corpus of the types of things you want to be able to recognize and feed it through here: http://www.speech.cs.cmu.edu/tools/lmtool-new.html http://www.speech.cs.cmu.edu/tools/lmtool-new.html If you try to use pocketsphinx to recognize arbitrary English (e.g. dictation) it's not going to work very well in my experience.