filtering a wav file

[lordy]

352kbps

noise with audio

yes

here is the picture attached
.............

that wont look right
i tried many filter like min-max-mean-gaussian-laplacian ..... i didn't get any result.

do exactly this
[y,fs] = wavread('2'); % there u will get fs which is 22050 in ur case

t= 1:fs;
x3 = y(1:fs);

f =abs(fft(x3));

figure, plot(x3)
figure, plot(t,f)


in time signal small amplitude which are continuous is noise.

 

[phongphanp]

You are going to design for Statistics or best representation about preserving , understanding , computerization ?

 

[foxbrain]

i made what u had told me about and here are the results attached.....
i guess the first figure is the file signal and the second is the signal in the time and frequency.
how can i delete the small amplitude (noise)?

 

[lordy]

dude it look like if you use any particular band of frequency filter it will block ur audio signal also. so any simple method or direct filtering is not going to help u.

how much time do u have for this? it is not easy task. u need to learn audio processing.

just check Independent component analysis for noise reduction.

check the link

**broken link removed**

 

[foxbrain]

i've got 1 to 2 weeks as maximum and i need it by matlab

 

[Djerly_NSSC]

use wavelet could do better
but you should know what kind of noise it is
or you could analysis it first of all

 

[Ismail Bagalkote]

good thoughts i will help u

 

[cherryman]

I thing it will be better to use STFT instead FFT. Try to use the spectrogram method in matlab. It will give You an information about frequencies in time slots. It's much simpler than doing it manually with FFT.
https://www.mathworks.com/help/signal/ref/spectrogram.html?searchHighlight=spectrogram

See the figure below. It should be rotated, but You can see that much noise is above 2.5kHz.
At first try to cut this frequencies with simple LP FIR filter. You can design it using fdatool in matlab.