How can I remove moire patterns from a cover with GIMP?

[Arseen]

The moire effect is bad.   

What scanner program you are using?
Could you take print-screens of you scanner options so we could try to find the option to remove the moire before scanning? 

[arny91]

The scanning software is XSANE.
it hasn't any descreen option except for the median filter. But isn't the descreen/derasterization option of the other scanning software a median filter, in fact?

Screenshot: http://www.mediafire.com/?m9qy7428mxve0cs

P.S: Neither the original hp precisionscan ltx, which couldn't be used anymore on windows 7 had descreen.

[Arseen]

Did some research and didn't find any leads to solving the problem.

Only what we can try is take a scan with full median filter on, and see if that removes the moire.

But isn't the descreen/derasterization option of the other scanning software a median filter, in fact?

That I don't know.

[arny91]

This is the back cover with median filter on, radius 2(it's the min value)

http://www.mediafire.com/file/95kq6cltlzufa7j/hybrid-back-median.tiff

[Arseen]

This is the back cover with median filter on, radius 2(it's the min value)

http://www.mediafire.com/file/95kq6cltlzufa7j/hybrid-back-median.tiff

What happens if you put bigger value?

[arny91]

The higher the value, the more the filter will blur the image. Just tried with a value of 3 and the characters are unreadable. Unuseful to post the scan.

[Arseen]

How are the pictures, it is normal that text has to be re-written.

[arny91]

Median filter (3)
http://www.mediafire.com/file/yfcb0e6l6nx7mub/hybrid-back-median-3.tiff

[Arseen]

Moire is getting removed better but the image is getting blurrier. 

Yeah I don't think this is doable, unless your scan software has sharpening setting aswell, altough that might lead the moire returning. 

Oh well can't win always.