bert2/DtmfDetection

LiveAudioDtmfAnalyzer seems not working

FrankBolleri opened this issue · 5 comments

FrankBolleri commented

I'm unable to run both the samples
How to detect DTMF tones through mic in, but with each audio channel analyzed separately and
How to detect DTMF tones in the current audio output
and i suspect there is something not working in LiveAudioDtmfAnalyzer

I am testing playing DTMF sound from cell phone app and the site http://onlinetonegenerator.com/dtmf.html

I am placing cell phone in front of my external microphone, as well of the speaker of my PC if I use the generator online.

Please consider that:

  • If I just use N-Audio, I am able to obtain correctly data from WaveInEvent micIn, and execute, for example, the FFT - so I have no doubt that my microphone is working correctly with N-Audio acquisition.

  • When testing scenario How to detect DTMF tones in the current audio output I have activated the listening of the microphone input in Windows audio properties.

  • If i use the example named How to print all DTMF tones in an MP3 file, but with each audio channel analyzed separately: it works well.

I hope this can help you to improve your library!

Thanks and regards,
Francesco

Expected Behavior

I'm expecting DtmfToneStarted and DtmfToneStopped events are raised.

Current Behavior

DtmfToneStarted and DtmfToneStopped events are never raised.

bert2 commented

Hi, thanks for the report and sorry for the late reply.

Have you tried using the example program?

bert2 commented

I was unable to reproduce your problem. I created a new .NET Framework console app, copied the examples and ran it while playing DTMF sounds via this video and my mobile phone touchpad. Both worked.

However, the website you linked didn't work for me either. I suspect there is something wrong with the site. Also, when analyzing microphone audio, I had to place my mic very close to the loudspeakers of my mobile.

FrankBolleri commented

Hi bert2
thank you for your hints.

I discover that in both case my failures seems related to the volume of the sound.
For both (generator website and the video 911) I have to keep very high volume, and in that way it works!

The environment is a room very quiet and seems a little strange to me to need so higher volume; excuse me but in my first attempt I have tried with a low volume, around a middle of the maximum possible.

Closing the issue, I'd like to express the wish to have some parameter for tune the sensibility of recognition process, if is possible to implement.
Or if that parameter is already existent, if you can indicate me please.

Thanks for your attention and for drive me to the solution.

Warm regards,
Francesco

bert2 commented

You can use NAudio to boost the volume of your audio stream before you pass it to the analyzer. I'm not sure how this is done exactly, but the documentation should help.

FrankBolleri commented

Ok, thank you very much for the support.

Great work!

Regards,
Francesco

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