I have run the following command:(adsbygoogle = window.adsbygoogle || []).push({});

c = wavread('sample.wav');

amplitude = log (abs(fft(c)));

and obtained the following plot:

[PLAIN]http://img179.imageshack.us/img179/8733/withoutplusone.jpg [Broken]

however, i was told to use this instead:

amplitude = log (1+abs(fft(c)));

and obtained the following plot:

[PLAIN]http://img146.imageshack.us/img146/4594/withplusone.jpg [Broken]

my question is: why do we have to take the log 1 plus amplitude, instead of just the log of amplitude.

thanks.

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# MATLAB: Fast Fourier Transform

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