how can i get a wave file of a particular duration

Actually i got a .wave file of some duration but i need a particular portion of that .wave file.i used wavsurfer software but its not working.i need a .wav file ranging from 2.9sec to 3.4sec can anybody pls help me with matlab code??

Answer 1

[Jan]

When you know the frequency of the signal, you can specify the wanted part in the inputs:

[y, Fs] = wavread(filename, [N1, N2])

Or the modern version in new Matlab versions:

[y,Fs] = audioread(filename, [N1, N2])

Without knowing the frequency, you can either import the whole signal and cut it afterwards, or obtain the frequency:

info   = audioinfo(filename);
Fs     = info.SampleRate;
Signal = audioread(filename, round([2.9, 3.4] * Fs));  % [EDITED, typo]

[Sony]

[...] = wavread(filename,[N1 N2]) returns only samples N1 through N2 from each channel in the file. but how to find samples from 2.9 to 3.4 sec?

[Walter Roberson]

As Jan wrote,

round([2.9, 2.4] * Fs)

except his 2.4 should have been 3.4.

That is, multiply time desired by number of samples per second to get the sample number.

[Sony]

how to get number of samples per second?

[Walter Roberson]

Do you see above where Jan did the wavread() ? The second output, Fs, is the sampling frequency. You can also get it without reading the file by using wavinfo() (older) or audioinfo() (newer)