On Fri, Dec 26, 2008 at 5:56 AM, Christopher Corbell <chriscorb...@gmail.com> wrote: > I'm working on an accessibility app for the visually impaired and was hoping > to use NSSpeechRecognizer. > > I've found it extremely difficult to get NSSpeechRecognizer to behave > predictably on my system. Does anyone on the list have experience with this > class & success with the Speech Recognition system preference panel? Any > tips or tricks? > > I find that that calibration dialog for the Speech Recognition settings > doesn't work at all for me. I'm using a pretty standard external microphone > (built-in to a Logitech Webcam) with an intel Mac Mini. I can see my signal > just fine and I'm speaking clearly in as accent-neutral a way as I can, and > still none of the test sentences ever highlights. Is a headset mic > typically required, or is there some other gotcha here? > > When I give NSSpeechRecognizer a very small and unambiguous command set, I > find it badly misses the mark. For example I might have "Play", "Next", and > "Stop" in my command set, and it will interpret "Next" as "Play", but it > will never interpret "Play" as a command - pretty unusable, I'm hoping it's > just a calibration issue.
I'm afraid I don't know a lot about this stuff, but since nobody else has answered yet, I'll give it a shot. >From what you describe I'd guess that your gain is not set well. You need a good strong signal when you speak, but it absolutely must not clip. If it's too quiet then I think that the recognizer won't realize when you're speaking, or won't be able to understand what you're saying when you do. If it's clipping then it will get a lot of distortion. Try to make it so that your speech just reaches the top of the green area. I've never used speech recognition extensively but I have played around with it a fair amount, and with a decent microphone that's properly calibrated, I haven't really had much trouble with it misunderstanding me, certainly not to the degree which you describe. You might also try recording yourself and then playing it back. Listen to see how it sounds. If it's distorted or otherwise of low quality then that will hurt recognition badly. > One last note - is there any way to do proper dictation with this class or > will it only recognize the preset command list you give it? I'm thinking > for example of prompting for a file name to save to, or a term to search on > - it would be nice to have true dictation, otherwise I'll resort to > providing an alphabet as a command set so the user can spell it out > (assuming I can get that to work). Alas, no dictation. The great thing about Apple's speech recognition is that it's speaker-independent and requires no training. However the state of the art for such things is that dictation requires training to a particular speaker's voice before it can work. So Apple's recognizer, by virtue of its capabilities in other areas, loses out on this capability. You'll have to go with your alphabet command set or some other idea that works with a predefined set of recognizable phrases. Mike _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
