Microphone Input Detection

[floydzep]

I would like to create a VI that actively detects if there is a signal present on the microphone input of my sound card.  I don't care to extract any information from the signal other than if it is above a certain threshold I set.  My vision is that I can see a virtual LED light up when I speak into the mic and it will turn off when I stop talking.  I would also like to record the "mute" events (start and stop points) with a timestamp relative to start of the aquisition. 

Any help would be greatly appreciated.

Thanks!

[floydzep]

Never mind, I figured it out.  I just used a "microphone record" VI I found on here and found out how to tap into the input signal.  Then I stripped all of the junk I didn't need. 

[NathanT]

Hello Floyd,
      Have you had a chance to look at the sound related shipping examples in LabVIEW?  The Developer Zone is also a very helpful place to search.  When I searched for "sound" there, the third search result was: Determining the Current Sound Volume With LabVIEW.
       Both resources can give you a great foundation for your application.

Cheers,

NathanT

[suneelkv]

Hi All,

Even i'm looking for same kind of application....

I would like to create a VI that actively detects if there is a signal present on the microphone input of my sound card.  I wnat  to extract the information from the signal and based on time i want to save them as 1.wav 2.wav......... 

I've already used the sound2 folder .llb available in examples....

But triggering the Record on and off i couldnt do that....

Any help would be greatly appreciated.

Thanks in advance....

Cheers,

Suneel.V

[Jennifer_R]

Hi Suneel,

Are you referring to the Record From Microphone VI posted here?  The output of that VI is of the Dynamic Data type, but you can use the Convert from Dynamic Data Express VI to convert the data to a numeric array.  If you have a threshold to detect an input signal, you can then use comparison and array VIs to analyze and process the data. 

[suneelkv]

Hi Jennifer,

I've used similar VI's available in the examples (Sound2) of Lab view folder and developed few VI's.

Please see the attached below.

The problem i'm facing is I coudlnt initiate the record option automatically.(manually starting the VI and stopping the VI- need to be autoamted)

And even the recorded 1.wav is not similar to the library wave file available with me..

Play the library wave file attached here with...

Looks like some problem with the sound format..

Please give a proper suggestion as to how to make these two .wav formats equal...

if these two formats are equal, i already designed a comparison technique which will compare two .wav files and gives the result as pass/fail..

Thanks in Advance.

Cheers,

Suneel.V

[Jennifer_R]

Hi Suneel,

If the wave file is not correct, I assume the data displayed on the Waveform Graph is not what you are expecting to see either.  Have you verified that your microphone is the source of the data? 

You can find information on the sound VI inputs, including the sound format, in LabVIEW Help.  If you display the Context Help for the Sound Input Configure VI, there are details under Detailed help. 

You may want to try the Express VIs linked in my previous post as well. 

[venkat001]

Hi,

I'm writing a program to acquire a sound through microphone and play it on speaker through sound card available in the PC. I have problem in program,

1).  If I increase the volume more than 40 db I'm getting delay in microphone signal and feedback signal on speaker.

2). Need to plot the sound pressure level graph.

Attached the VI below.

Any suggestions would be greatly appreciated.

[nvnewbie]

Hi all,

I have a USB microphone (Brand is Polar and USB interface) to realtime measure the sound level, I found an example in Labview folder. But it seems not work, I can't record any sound, I am spend an hour to check it (change other id), I haven't idea:mansad: why it don't work,  (it works fine in windows XP with sound recorder and also work when use handfree to mic in recording). Attached the working example for Labview.Please give help. Thank you!

[JD_war_eagle]

Hi nvnewbie,

I would check in the Windows Device Manager to ensure that the device shows up as a sound device.  If it does, then you should be able to access it via the device ID of the Sound Input Configure.  You may also wish to look into the Acquire Sound Express VI, which may simplify the acquisition process.