shSpeech was originally developed by Eric Knepfler specifically for SH4. TomCatTwo (I only know his screen name) then did the conversion for SH3. The package has also been adapted for SH5, but there is a speech recognition capability imbedded in SH5 which is more widely used.
shSpeech is a stand-alone program which runs in background mode with SH3, SH4, or any other game program. It translates voice commands into keystrokes and mouse actions, like button clicks and dial settings. Because the mouse movement is GUI-dependent, some tailoring may be necessary to adjust it to the GUI you prefer. The good news is that it is pretty easy to make whatever changes you want. Out of the box, shSpeech will support ALL SH keystroke commands, so you can do a lot right off the bat. Changes require no programming skill whatsoever, just a very basic knowledge of how to make and modify simple spreadsheets using either Excel or a similar spreadsheet program. The ease and flexibility are what make spSpeech so attractive. You can adapt it to any game that uses keystroke commands, for example. And it is very easy to add your own voice commands.
The kick is when you are at the bridge view of your Gato and say: "Take 'er down." and your crew goes about diving the boat!
"Sparks, put on some music from stateside. Nav, set course for Pearl"
Remember, real skippers didn't push buttons. They gave orders.
http://knepfler.com/shSpeech/