how do you improve images like this ? [moire]

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

is that pattern an artifact from a scanning process ?

http://25.media.tumblr.com/1899625d54de ... 2_1280.jpg

what technique could improve this image ?

YAFU · **Joined:** Nov 09, 2011 **Posts:** 726

What a strange pattern has that image.
I guess with some despeckle and smooth techniques, GIMP Despeckle, G'MIC Remove Hot Pixels and G'MIC Smooth anisotropic.
But I do not think it's possible to remove that pattern totally only using filters.
I do not see interlace distortions in the image,so deinterlace I do not think is useful. This pattern seems to be because the canvas where the image has been printed.

Edit:
Only with filters. Remove Hot Pixel, GIMP Despeckle, Smooth Anisotropic, very little Sharpen deblur

Akros · **Joined:** Jan 10, 2013 **Posts:** 863

Hi Yafu, this filter (Remove Hot Pixel) has the G'mic?
That I do not know.v :puzzled

I did a highlighted in color, then used the filters Despekle and (G'MIC) Smooth thin brush.

I think for a good result, the clone tool would need

YAFU · **Joined:** Nov 09, 2011 **Posts:** 726

@Akros, yes. Under Repair menu.

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

thanks Yafu and Akros

improving images is beyond my knowledge, you both clearly know your stuff

sallyanne · **Posted:** Tue Sep 03, 2013 10:05 am **(#6)**

Just ran Ian's noise reduction on it. (Is in G'MIC)

Cool job guys. Mine looked a lot clearer before I uploaded it.

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

Used G'MIC Fourier Transform to remove the frequency noise (regular pattern noise), then one step of G'MIC anisotropic smoothing.

Attachment:

restored_tumblr_mseavafWGk1qdkmano2_1280.jpg [ 1.32 MiB | Viewed 6280 times ]

he4rty · **Joined:** Aug 30, 2012 **Posts:** 2174

Good work on the photo, wouldn't know where to begin.

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

sallyanne wrote:

Just ran Ian's noise reduction on it. (Is in G'MIC)

thanks sallyanne !

Ronounours wrote:

Used G'MIC Fourier Transform to remove the frequency noise (regular pattern noise)

the direct transform gave me a strange all grey image as output and the inverse transform an error

Akros · **Joined:** Jan 10, 2013 **Posts:** 863

Ronounours wrote:

Used G'MIC Fourier Transform to remove the frequency noise (regular pattern noise), then one step of G'MIC anisotropic smoothing.

Hi guys!
Where exactly is this filter (Fourier Transform) located?

sallyanne · **Posted:** Tue Sep 03, 2013 5:32 pm **(#11)**

great job Ronounours

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

Akros wrote:

Where exactly is this filter (Fourier Transform) located?

G'MIC -> Spectral Filters -> Fourier Transform

Akros · **Joined:** Jan 10, 2013 **Posts:** 863

Esper wrote:

Akros wrote:

Where exactly is this filter (Fourier Transform) located?

G'MIC -> Spectral Filters -> Fourier Transform

Thx Esper! :bigthup

But cant see the preview using that filter.

With option --> Transform Direct, the preview is transparent;
With the option Transform Inverse, No preview avaliable.

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

same here

Akros · **Joined:** Jan 10, 2013 **Posts:** 863

Esper wrote:

the direct transform gave me a strange all grey image as output and the inverse transform an error

The direct transform gave me a strange all grey image too, and changed the appearance of how layers are displayed in layers dialog.

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

yep

i guess Ronounours can solve that mystery

sallyanne · **Posted:** Wed Sep 04, 2013 2:37 am **(#17)**

Akros wrote:

Esper wrote:

the direct transform gave me a strange all grey image as output and the inverse transform an error

The direct transform gave me a strange all grey image too, and changed the appearance of how layers are displayed in layers dialog.

Happened to me too

Rod · **Joined:** May 16, 2010 **Posts:** 16152

I got some pretty good results by just using Repair>Smoothing - anisotropic with these settings.

Results-

gerard82 · **Posted:** Wed Sep 04, 2013 9:38 am **(#19)**

To Esper,
Since no one said anything about the origin of the strange pattern:
It is not caused by scanning,on the contrary this is a good scanner.
The picture must have been from a glossy magazine or similar.
The machine that prints it uses this pattern to regulate the amount of printing ink.
Without it the colors would bleed.
Gerard.

wbool63 · **Posted:** Wed Sep 04, 2013 9:40 am **(#20)**

Another quick way to get a reasonable image is gaussian blur 5, sharpen 60, duplicate the layer overlay mode 40 %, flatten and sharpen 60 , save as jpg