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Background - Foreground - how to work on the separation?
#10
good day - dear froemds. 


for me its helpful  if i write things down by hand or step by step, things i have to do. 

well i have made up my mind and tested some steps in doing so:  i hope that this might be helpful for others too. 



first of all: i take a screenshot of a meaningful frame from the image.
then i open the image in GIMP (File > Open).

note:  (Optional): If the image is colored, convert it to grayscale (Image > Mode > Grayscale). This simplifies edge detection.

in the next step i think its important to extract the dominant edge
therefore i need to go to the menu: Filters > Edge-Detect > Edge. 
BTW: hmm - there are other options like "Sobel" or "Laplace", but "Edge" usually gives a clean result for network structures.
Hmmm -  for the fine-tuning: If the line is too weak or too strong, we need to adjust it using Colors > Curves or Colors > Brightness/Contrast. The goal is a crisp black-and-white line network.

Result: wou now have a base layer (let's call it "Base"), which ideally looks like a white surface with a black web of lines on it.
    

Quote:+---------------------------------------+
|  Base Layer                           |
|   .-----o      .-----o                    |
|   |      \    /         |                     |
|   o       o--o       o                    |
|  / \     /    \       / \                     |
| o   o---o      o---o                    |
+---------------------------------------+

Fig. 1: our Base layer with the extracted line network.

in the next step i think it is important  to take care for the "tracing Dots and Connecting Them 

and here i have the important part - which is allways a challenge for me . . the Working with Layers and Paths

i think its important - to  open a second layer - that is imporant:  for  the creative par that starts now: On a second layer, i select specific nodes and connect them. The Paths Tool is perfect for this.

Step 3: Create a New Drawing Layer

now i create a new transparent layer above the Base layer. well i name it "My_Network".
 Important: i need to mak  sure this new layer is selected in the Layers dialog.


 see below - how it is menat: 

Quote:+---------------------------------------+
|  My_Network (Transparent)     |  <-- all my drawing goes here
+---------------------------------------+
|  Base                                 |
|   .-----o      .-----o                |
|   |      \    /          |                |   
|   o       o--o       o                |
+---------------------------------------+


Fig. 2: The layer structure. The drawing layer sits on top of the base.*
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Messages In This Thread
RE: Background - Foreground - how to work on the separation? - by saint_m - Yesterday, 10:14 AM

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