Venetian blind effect

[karlkane]

HI everyone,

I am both new to this forum, and new to gimp/photo shop, and am in a bit of a pickle.
I have been asked to edit a couple of pictures in a particular way which has me kind of lost. Essentially I have been asked to serrate the image into vertical strips or columns of a particular pixel width.
There are two pics, L1 and R1. These are to be cut into vertical strips (say 100 strips but this will change) and laid out left pic strip 1, then right picture strip 1, then left picture strip 2, right picture strip 2, L3 then R3, L4 then R4 etc etc. Like a vertical blind.

However, a gap (or black strip - B) of a particular pixel width between each strip is also necessary. So it will run L1 then B then R1, L2 then B then R2, L3 then B then R3 etc etc. 

Apologies if this turns out to be a very simple or idiotic question, but I am very new to this. Steep learning curve I expect.

Something akin to the image below, with the white stripes being replaced with black stripes.

[Ofnuts]

With my ofn-shred-layer script you shred each image, and then combine the two shredded image using them as layers (you shift the top one). Then you add a brackground layer if necessary.

   

[rich2005]

Edit: Ninja'd again by the plugin author. There might be someting of use in this litte example.

------------------------
Something like this ? 40 second demo https://i.imgur.com/ARfHEb2.mp4

This is using one of Ofnuts plugins shred-layer.py from http://sourceforge.net/projects/gimp-too...s/scripts/ Look for ofn-shred-layer.zip dated 2017-11-29

There is one caveate: the image has to be a multiple of the strip size. You might have to add some padding and crop that out at the end.
Otherwise it is apply to each image
Stack the shredded images as layers
Move one of the layers to suit
Image -> Fit layers to canvas might be required
Merge layers if required.

[karlkane]

Guys,

Thanks very much for the help, I think this maybe the solution. I do however have one question and I can already hear the groan lol. The script that you are using, hoe do i use it/open it?

[Ofnuts]

See the installation instructions at the bottom of the download page.

The ZIP contains a HTML doc, worth reading.

Once installed, it is at the bottom of the Layer menu in the image window (Shred... entry).

[rich2005]

Looking at alternatives that are not too picky on image sizes. This using the gimp_gmic_qt plugin. A big plugin with hundreds of filters (something for everyone) http://www.gmic.eu There is a Windows installer.

One of the filters in the Arrays & Tiles section is Tiled Isolation which works with percentages. Say I want 12 strips, then I use 8.33% as a value.

The plugin UI looks like this and the essentials are (1) for the number of strips (2) the spacing which is a percentage of the strip. (3) not needed (4) set the input to all layers and the output to a new image.

   

That gets two layers overlayed. Use Layer -> Transform -> Offset to nudge a layer into position.

and as a 1 minute demo https://i.imgur.com/cxt6Byx.mp4

[sallyanne]

Just figured something out. Make a mask using the scanlines in GMIC. It's under degradations. Open a blank canvas the same size as your images (preferrably white) and then open the filter in GMIC. Use all the defaults but you may want to make the bandwidth thicker or thinner. Press ok.
Back in gimp add a black layer and move below your scanlines layer.
Select the scanlines layer and put on hard mix layer mode. merge down and if need be rotate your mask.

Now for your first image
1. Open it and add a white mask (full opacity).
2. Copy the mask you just made then turn the eye off so it is invisible.
3. Go back to your white mask and select it,
4. click on edit - paste as new layer in place - you will have to anchor it.
5. Apply mask
Now with the second image - Go to the mask you made and reverse the colours. Colour - invert.
1. Open your image and add a white mask
Follow 2-5.
Now you should have two images in alternating strips

[Krikor]

"Just figured something out".

Using ➤ Blur-Pixelize, might also be an option. 

I used the values as shown below.
Remembering to apply Alpha to the Background color!

"Move one of the layers to suit
Image -> Fit layers to canvas might be required"

I applied a mask just for clarification purposes that each image is on a different layer.
   

[PixLab]

(02-25-2023, 12:07 PM)rich2005 Wrote: Looking at alternatives that are not too picky on image sizes.

Indeed too picky, quite unfriendly


   

That's terrible, after few guesses I gave up, by seeing this window too often in a row, I got a PTSD...
I came to hate this alert/window, same with the ofn-tiles or ofn-tile-thing  

@Ofnuts, suggestion: let your script shred it or tile it, the last one will be what it will be, but we don't want to spend 5 minutes guessing or calculating what's the multiple of the image size, or at least your script should tell us what should be the image size to be a multiple of what we want to shred,

Or just shred without stopping the script > as in all cases the size of the last one will let us know on how much we need to "cut/shrink the image.... and people who are not picky with the last one not being the same size > will be happy as well, or will just delete it (I will).

Or add the necessary blank/transparent space on each side for the layer to become a multiple of the chosen number, then let shred it

[Ofnuts]

(02-27-2023, 02:26 AM)PixLab Wrote:

(02-25-2023, 12:07 PM)rich2005 Wrote: Looking at alternatives that are not too picky on image sizes.

Indeed too picky, quite unfriendly




That's terrible, after few guesses I gave up, by seeing this window too often in a row, I got a PTSD...
I came to hate this alert/window, same with the ofn-tiles or ofn-tile-thing  

@Ofnuts, suggestion: let your script shred it or tile it, the last one will be what it will be, but we don't want to spend 5 minutes guessing or calculating what's the multiple of the image size, or at least your script should tell us what should be the image size to be a multiple of what we want to shred,

Or just shred without stopping the script > as in all cases the size of the last one will let us know on how much we need to "cut/shrink the image.... and people who are not picky with the last one not being the same size > will be happy as well, or will just delete it (I will).

Or add the necessary blank/transparent space on each side for the layer to become a multiple of the chosen number, then let shred it

Too many options.. Add on the left? On the right? Add transparency? Background color? Something else? The best way for the users to tell is to handle this themselves.

And frankly, those who use nearly prime numbers such as 51 and 1077 know exactly what they are doing and know what a multiple is (as do most people using Gimp.... the "multiple" is taught in  5th grade (students around 12yo) in France...)