Interfacing with a customized wireless microphone through LV

[xhuo]

Hi,

I am trying to interface a customized wireless microphone with a commercial speech recognition software (Dragon Naturally Speaking) through LabVIEW 2009. So far I managed to read the audio data stream into LabVIEW. But I have no idea how I can feed this data to the speech recognition software. It seems to me the software should receives audio data from microphone, essentially the sound card, by default. It means I should write the audio data to the output buffer of the sound card. But I don't know how to do that.

Does anyone have similar experience? Any help is appreciated!

Thanks a lot.

Xueliang

[xhuo]

I forgot to mention that the audio data is received directly through USB and the sound card is bypassed. I had difficulty in feeding the audio data to the speech recognition software. Someone told me I have to write a specific driver for my device. I was wondering if there is a simpler way to do this in LabVIEW.

Thanks,

Xueliang

[Matt_McLaughlin]

Hi Xueliang,

For a good jumping off point, try looking at the code and discussion on this page: Voice Recognition in LabVIEW . This page goes over older software versions, but it should give you some ideas about using Dragon Naturally Speaking with LabVIEW.

When you say you had trouble feeding the audio data to the speech recognition software what specifically do you mean? How are you trying to interact with the software?

[xhuo]

Hi, Matt,

Thanks a lot for your reply. I have downloaded the example code in your link and played around with it. I found it is not what I exactly want. My problem is not related to using Dragon Naturally Speaking in the LabVIEW, but actually using LabVIEW as a bridge to receive the audio data stream through USB and then send audio data to the Dragon Naturally speaking in real time. In this way, I can use my customized USB microphone with Dragon.

What I meant of  "having trouble feeding the audio data to the speech recognition software" is that I don't know how I can make the SR software recognize the audio data that is received in LabVIEW. If we use a normal microphone, the data should be received directly from sound card. I want to know if there is a way that we can bypass the sound card and directly give Dragon the audio data that is  received from USB. 

I hope I have made the problem a little more clear. Look forward to your reply.

Thanks,

Xueliang

[Matt_McLaughlin]

Hi Xueliang,

It sounds like the issue here depends on how the Dragon Naturally Speaking software is expecting to receive the audio data. Do you know what type of data their product works with? On their website, they have a page regarding Hardware Compatibility, which may be useful to check out. You may also want to try contacting their product support to see if this a plausible way of using their software.

I hope that helps!

[AnalogKid2DigitalMan]

This may be considered a Rube, but can you output the processed data from LabVIEW to the sound card connected to a speaker, and then have a microphone placed near the speaker to act as the input to Dragon? Dragon is a pretty cool application, by the way!

-AK2DM

[xhuo]

Thanks Matt. You post is very helpful.

You are absolutely right. I need to find out how the software is expecting to receive the data. I have no idea what type of data Dragon works. I should call their technical support. They charge considerable service fee for this kind of technical questions.

[xhuo]

Hey, AK2DM,

Thanks a lot for your suggestion. It is a very practical idea. I actually have thought about it. I think a better solution is to use an audio cable to connect line in and line out of the computer so the output of speaker will be fed to the input of Dragon. I also found a software called virtual audio cable, can do the similar thing. I am gonna give it a try!

Thanks,

Xueliang

[AnalogKid2DigitalMan]

Be careful directly connecting the audio out to microphone in jacks. The audio out signal may be on the order of 100's of mV to over a volt, while the microphone input is expecting a signal on the order of 10's of mV. Start out with the volume at a very low level. There may also be an impedance mismatch between the two.

You may want to check the specs of your sound card for the output/input levels and impedances.

-AK2DM