Simulate old bw photo printing effect

[Carla]

Hi everybody,

I'm trying to achieve this old printer effect described here for photoshop with gimp as I do not own ps and just cannot realize it:
 
https://graphicdesign.stackexchange.com/...rt-effects
 
Can anybody check whether this can be done with gimp - or is gimp lacking some required features to achieve this? Is it feasable after all? I use gimp 2.10.8 and all I get is my grayscaled picture (background) with overlaying parralel horizontal b/w-lines (layer 1). Like a zebra over a photo. But I cannot realize this certain effect that the lines get thinner or thicker as the gray gets less or more intense and that the two layers seem to blend.
Does anybody have an idea on this?

Thanks very much for your time and effort and sorry for my utter noobiness.

Cheers,
Carla

[Ofnuts]

Several ways to do that:

1. The Engrave filter
   
2. My old luminosity-tiler script: you replace the image by tiles that have the same equivalent luminosity, if tiles are 1px wide and contain a widening group of black pixels, the result is lines of varying width.
   
3. My more recent ofn-engraving script.
   

[Carla]

Thansk Ofnuts for your quick help.
The engrave filter does not quite yield what I aim for but it is a cool option anyway.
I tried your recent ofn-engraving script. However, I got error messages for both options (varying dashes/thickness).
Varying dashes says "'NoneType' object has no attribute 'strokes'".
Varying thickness - the option that is most interesting for me - says "Calling error for procedure 'gimp-drawable-edit-stroke-item':
Procedure 'gimp-drawable-edit-stroke-item' has been called with value '-1' for argument 'item' (#2, type GimpItemID). This value is out of range." and "Procedure 'gimp-drawable-edit-stroke-item' has been called with value '-1' for argument 'item' (#2, type GimpItemID). This value is out of range." (standard values applied to a png-picture).
Do you have an idea what this might mean or how to fix this?
Thanks again,
Carla

[Ofnuts]

(08-05-2020, 09:18 PM)Carla Wrote: Thansk Ofnuts for your quick help.
The engrave filter does not quite yield what I aim for but it is a cool option anyway.
I tried your recent ofn-engraving script. However, I got error messages for both options (varying dashes/thickness).
Varying dashes says "'NoneType' object has no attribute 'strokes'".
Varying thickness - the option that is most interesting for me - says "Calling error for procedure 'gimp-drawable-edit-stroke-item':
Procedure 'gimp-drawable-edit-stroke-item' has been called with value '-1' for argument 'item' (#2, type GimpItemID). This value is out of range." and "Procedure 'gimp-drawable-edit-stroke-item' has been called with value '-1' for argument 'item' (#2, type GimpItemID). This value is out of range." (standard values applied to a png-picture).
Do you have an idea what this might mean or how to fix this?
Thanks again,
Carla

ofn-engraving requires a path, that typically consists in regularly spaced lines (straight of wavy) or concentric circles. This path is stroked with lines of varying width to achieve the effect.

You can usually generate such path using other scripts in my collection. ofn-path-inbetweener will for instance generate regularly spaced lines by interpolating lines between two paths.

My scripts that come as a ZIP usually contain an HTML file that explains how to use the script and provide examples, this is true for both ofn-engraving and ofn-path -inbetweener.