Noise reduction in voip (skype)

[d91]

Hi people..

I am thinking about noise reduction in skype.. Like.. the standard annoying buzz the microphone usually gives, or something that is always there, but you can't get rid off.
I am using matlab and made 2 samples, 1 sample containing the noise + speech, and 1 sample containing only the noise.
I made a spectrogram off that and.. the frequency of the noise (and the intensity) is very much in the speech bandfrequency, which makes it ofcourse very hard to filter..
The idea I have is (all static now, but for an application later) take a sample of a person talking for about 3 seconds. Then a sample of the person not talking for also about 3 seconds.
Then, subtract the current stream of voice (I hope you get what i mean) with the sample of noise that is recorded..
Is this a good idea to try?

Or does anyone have an idea to get the noise out of a sample, without distorting the voice.. (the literature I found couldn't help me too much on it :/)
Another idea is to make a bandpass filter, which passes frequencies from 300 Hz to about 3 KHz, but ofcourse if the noise is within the 300 Hz - 3KHz range, then the problem still remains..

I am not an expert on DSP but I have some basic knowledge I guess, hopefully enough to fix this =)
Also, this is for a school assignment and a classmate and myself came up with this project.

Thanks in advance.. hopefully I have a reaction soon

Davey

 

[zorro]

The idea I have is (all static now, but for an application later) take a sample of a person talking for about 3 seconds. Then a sample of the person not talking for also about 3 seconds.
Then, subtract the current stream of voice (I hope you get what i mean) with the sample of noise that is recorded..
Is this a good idea to try?

Hoy want to cancel the noise in voice+noise1 substracting noise2.
You can not expect that the noise recorded in the second is the same as in the first record. You would get only more noise.
If the problem is ambient noise, there are techiques of noise cancelletion usinh one (or more) extra microphone.
Regards

Z