[Octave-patch-tracker] [patch #7588] synthesis.m fails when w_size=inc

[anonymous]

URL:
  <http://savannah.gnu.org/patch/?7588>

                 Summary: synthesis.m fails when w_size=inc
                 Project: GNU Octave
            Submitted by: None
            Submitted on: tor 28 jul 2011 22.46.16
                Category: None
                Priority: 5 - Normal
                  Status: None
                 Privacy: Public
             Assigned to: None
        Originator Email: address@hidden
             Open/Closed: Open
         Discussion Lock: Any

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Details:

For rectangular windows the signal can be fully reconstructed even when the
window size is equal to the increment.

But synthesis fails with an error (invalid row index = 0). To reproduce run:

x=rand(1024,1);
[y,c]=stft(x,128,128,64,3);
x2=synthesis(y,c);
max(abs(x2-x)) % validate expected result

The attached patch fixes the problem but also affects synthesis so that the
resulting signal starts earlier. Ie. previously this was fine

x=rand(1024,1);
[y,c]=stft(x);
x2=synthesis(y,c);
max(abs(x2-x(28:987))) % validate expected result

But with the patch this has to be changed to

x=rand(1024,1);
[y,c]=stft(x);
x2=synthesis(y,c);
max(abs(x2-x(29:988))) % validate expected result



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File Attachments:


-------------------------------------------------------
Date: tor 28 jul 2011 22.46.16  Name: synthesisfix.patch  Size: 367 B   By:
None

<http://savannah.gnu.org/patch/download.php?file_id=23712>

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Reply to this item at:

  <http://savannah.gnu.org/patch/?7588>

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