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Tue, 22 Jan 2013 17:25:09 +0000
Spectrogram
http://www.mathworks.com/matlabcentral/newsreader/view_thread/325980#896015
Matthew
hello,<br>
<br>
I'm trying to write my own spectrogram function. <br>
<br>
Would something along the lines of:<br>
<br>
I=abs(fftc(E*G)).^2 <br>
<br>
work well? the fftc is pretty much just a fourier transform, E is my input data and G is just a gaussian function that I'm using as a gating function. I plan on altering the width of the Gaussian later on to help with a more usable spectrogram, but would this type of code actually give me a spectrogram?<br>
<br>
thanks!

Tue, 22 Jan 2013 23:30:14 +0000
Re: Spectrogram
http://www.mathworks.com/matlabcentral/newsreader/view_thread/325980#896049
Sadik
Hi Matthew,<br>
<br>
If I know it correctly, you need to use overlapping windows of data, each of which will be windowed with a Hamming window or so to avoid Gibbs ringing. The fourier transform of these windows will then be put into columns and the resulting matrix will be displayed. <br>
<br>
If you have not already, you may want to google shorttime fourier transform [STFT] in the context of speech processing.<br>
<br>
Best.