Old postcard scan

Hello everyone, i have tried to scan an old postcard.

How can i get rid of the print “effect”? In Italy i call it retinatura, maybe it’s called halftone printing in english.

here you can find the scan: SwissTransfer.com - Envoi sécurisé et gratuit de gros fichiers

Thank you in advance.

Ciao @ggc,

Search for Gimp remove raster
and gimp fft

Cord. Sal.,
Claes a Lund, Svezia


Thank you, i have tried by hand with g’mic fft and after with the g’mic repair-descreen plugin that in a click does the same and maybe even better!


Hello, I use G’mic descreen for that, works fine for scans of printed materials.

On the picture below: left original scan, right after descreening, both at 100%.


yes it’s the one i mentioned.

btw, how do i call it from commandline gimp? I have almost never use gmic from commandline, but haven’t found a way to call this particular filter.

In the GIMP, I applied 2.5 px Gaussian Blur, downsized 50% cubic, up sized 200% cubic, voila

Effect reduced but not “got rid of”

full size here: http://kronometric.org/phot/temp/CartolinaCaviLavagna-Viaggiata1968%20gimp%20Ted.jpg

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From the commandline, it used to be ‘fx_pahlsson_descreen’.

But when I use this now, with a newer version of gmic, it says

[gmic]-1./ *** Error *** Unknown command or filename ‘fx_pahlsson_descreen’.

When I use this filter from Gimp and say ‘copy command to clipboard’, it outputs exactly the above string.

So we must ask @David_Tschumperle what’s going on…

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The difference between the command line tool and the GIMP plug-in is that the CLI tool does not embed the gmic-community filters by default.
fx_pahlsson_descreen is a command defined in the community filters.
$ gmic update allows to get this command back in the CLI tool.

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Thanks David, that worked!

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ggc, here’s the command to descreen your postcards in batch, assuming you store them in a folder called postcards :

cd ~/postcards
for i in *
	gmic input $i fx_pahlsson_descreen 0 output descreen_$i
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That is exactly what i wanted to do, thank you!

You’re welcome !

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Fun with G`MIC Descren and GIMP GEGL


You can also achieve good results with the following filters in GIMP with G’MIC:

G’MIC>Testing>Iain Fergusson>Iain Remove Pattern



You can optionally combine the results of both filters with Layers in GIMP.

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