Post a reasonable sized section of one of your images showing this striping so we can see what you are talking about, as the image you sent me directly showed no such striping and nothing in the spectrum of the FFT to indicate that there was something to filter there.



Hello,

I have some sat images with redundant noise in them. Mainly the noise is one
AKA banding/striping, whereby the sensor used for obtaining the image on the
sat induces some errors and there is a general effect of parallel equally
spaced horizontal lines across parts of the image...

Now, the removal procedure can be done in 2 ways I gather and I would like
some ideas from experts on this list as to how implement both of them using
imagemagick's command line utilities..

1) Using a noise removal filter.
Which kind of filter and kernel would I need to do this? A low-pass filter?
Made how?

2) Using FFT
Converting the signals to frequency domain star diagram with FFT, removing
the "Stars" , using the inverse FFT to reconvert to the original spatial
domain and getting a clean noiseless output image..

For the FFT part, I have installed Sean Burke's implementation of the FFT /
inverse FFT and it does the job quite well... Only problem now is what to
use to filter the frequency domain "star diagram" and remove the stars
before reconversion by inverse FFT...

Thanks in advance for you time..

--
Mattia
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