Affinity Photo: Remove really strong grain/noise on (old) scans of old documents?

[relexx]

Hi everybody!

I have now searched half the Internet for various approaches, but unfortunately not found the right answer.
Maybe someone here in the forum can help me.

I have a scan of a document, which unfortunately is not very good...

Using various live filters to reduce the noise doesn't help here, unfortunately, as the image noise is very irregular and has a large gap. Since I'm new to using Affinity Photo, I haven't found any other solution (via edges?).

Can anyone help me with this? If not, I'll have to come up with a "manual" solution.

Thanks!
relexx

[firstdefence]

Tried a few ideas but the closest I can get is using either the Threshold filter or the posterise filter set to 2, even then there will still be a fair amount of manual erasing.

[thomaso]

For example: Mainly a curve adjustment. The blur can help to remove small grainy spots affected by the curve lights then, while the thicker strokes get less affected.

[RichardMH]

Put this through Topaz De Noise then Frequency Separation back in Photo. Turned up the exposure on the Low Frequency layer and adjusted the levels on the High frequency layer. Then a bit of fiddling with HSL and threshold.

[firstdefence]

I went the manual erase path using the Pixel too set to white, one of the benefits here is the pixel tool is square and this lends itself nicely to this task and it didn't take long to get it to this stage, I'd even consider stopping at this point. One thing to note here is not to make the scan too perfect, leaving the lines slightly raggedy gives it a bit of authenticity. I used the Erase white paper filter and set a green background for effect.

[Pete_2022]

Hi Relexx,

I'm not sure if this is what you're after but I played around with your image and attached the results (png + affinity file).

Use "Level" to clean up majority of noises as well as darken the lines:
- Layer -> New Adjustment Layers -> Levels
Black Level -> Increase
White Level -> Decrease
Gamma -> Decrease
(NOTE: Instead of trying to run "Level" once, I find using "Level" twice yields better results.)
(ALTERNATIVELY: You can also use "Threshold" to do this part quickly; but it doesn't give you as much controls to play with.)

Now to remove the last bits of noise, I first selected the white areas and then applied a smooth selection to add the noise to the selection before deleting them leaving only the edges.
- Select -> Selection Layer from Intensity
This will select the more luminous areas (i.e. white).
- Select -> Smooth
This will grab the last bit of noises along with the selected white areas.
Set it to as high as it takes to remove the noise selections. I had to set it to 2 px.
- Finally hit "Delete" and you're left with just the dark lines.

(OPTIONAL) Added a white background using "Layer -> New Fill Layer".

Hope this is what you're after. I've never done this before, just playing around for fun.

 

TEST__Clean_Noise.afphoto

Edited January 18, 2023 by Pete_2022

[relexx]

Wow!

Thanks everybody! Every single result from you is much better than what I have achieved. I'll apply your suggestions to the various scans and pick the best one.

@RichardMH As far as I understand, Topaz is paid, correct? Since I'm a beginner, I'll look at everything but shy away from costs 😉 .

Thank you very, very much!
relexx

[loukash]

Diffuse Glow filter:

Plus some adjustments to increase contrast or decolor as necessary.
Also keep in mind that the stack order matters.
(The group is only there to turn them all on and off with one click.)

[albertkinng]

You can do that with one click on Pixelmator Pro. That's basically the newest feature now. I always have Pixelmator on the side for specific needs. One click background remover, editable PSD exports and video photo FX. Basically you can save a lot of time with those one click features. 

[firstdefence]

Hmmm! Pixelmator Pro Edit > Remove Background result.