[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: FFT - Spectrum Analyzer
From: |
Peter |
Subject: |
Re: FFT - Spectrum Analyzer |
Date: |
Mon, 11 Jun 2012 23:50:55 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 |
On 10-06-2012 00:27, Renato S. Yamane wrote:
Hi,
Anyone knows an way to analyze, with Octave, the Spectrum Frequency of a
digital media file (like an MP3)?
Something like this: http://img268.imageshack.us/img268/6345/bassiloveyou.jpg
For a long, non-stationary signal, you probably want to estimate the
power spectral density of the generating stochastic process (lots of
fancy words). This is done by the computing a "Welch periodogram".
So long story short: type
pwelch(input_signal,hamming(200));
and play aroung with the length of Hamming window until you get the
display you want. Octave's pwelch does not seem to plot on a dB scale,
so you might want
plot(20*log10(pwelch(input_signal,hamming(200)));
instead.
Cheers,
Peter.
- Re: FFT - Spectrum Analyzer, (continued)
- Re: FFT - Spectrum Analyzer, Sergei Steshenko, 2012/06/10
- Re: FFT - Spectrum Analyzer, Thomas D. Dean, 2012/06/10
- Re: FFT - Spectrum Analyzer, Markus Bergholz, 2012/06/10
- RE: FFT - Spectrum Analyzer, Damian Harty, 2012/06/11
- Re: FFT - Spectrum Analyzer, Juan Pablo Carbajal, 2012/06/11
- Re: FFT - Spectrum Analyzer, Sergei Steshenko, 2012/06/11
- RE: FFT - Spectrum Analyzer, Damian Harty, 2012/06/11
- Re: FFT - Spectrum Analyzer, Francesco Potortì, 2012/06/11
- Re: FFT - Spectrum Analyzer, Robert T. Short, 2012/06/11
- Re: FFT - Spectrum Analyzer, Sergei Steshenko, 2012/06/11
Re: FFT - Spectrum Analyzer,
Peter <=