CONV2 Overlap-add Method

Overlap-add method of CONV2 using FFT2.

Description

CONV2OLAM Overlap-add method of CONV2 using FFT2.

See readme.txt for more informations.

Please contribute if you find this software useful.

Report bugs to [e-mail]
 
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  Luigi Rosa
  Via Centrale 27
  67042 Civita di Bagno
  L'Aquila --- ITALY
  email [e-mail]
  mobile [phone]
  http://utenti.lycos.it/matlab
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• MATLAB release: MATLAB 6.5 (R13)

[Ila Fiete]

This is a simple code for 2-d convolution, based on the built-in matlab routine for 2-d fft. You can write it easily yourself, but this code is pretty clean and straightforward.

For large matrices, filter2 or conv2 are v. slow in matlab for large matrices. This code leads to a considerable speedup, by a factor of 5-10 on my machine, when I convolve a 500^2 matrix with a 100^2 one.

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[Jason Jury]

Nice straightforward m-file. Benchmarked on AMD-64 with Linux. Run time for convolving 2 500x500 matrices (with zero-padding) was 1.5 seconds; same problem with 'conv2' command took 490 seconds. For large problems with conv2olam, the run time scales as N^(2.2), for NxN square matrices. With conv2, run time scales as N^(4.6).

[Usman Khan]

Excellent work. Must be appriciated.

[Kiran Bhagat]

Beautiful work...

[Till]

They way i understand it it can only handle matrices with a maximum size of 2.^13 = 8192. It would be nice if bigger matrices would work as well.