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+--- Thread: White lines around cut out layers (/Thread-White-lines-around-cut-out-layers)
White lines around cut out layers - adam - 05-20-2022
When cutting out a part of a flat image to create a new layer this generates a white line around the new layer. This is particularly noticible if I use paste in place.
I have attached two images before where the image is flat and the next where I have cut out the chair and the footstool. I would expect as the chair and footstool were part of the image before and cutting them out and pasting them in place would still create a seamless image but there are white lines as seen in the second image.
Is there some setting I have not changed that is causing this or something I am doing wrong?
RE: White lines around cut out layers - rich2005 - 05-20-2022
Have to confess, I do not really get-it from your description. The light border usually occurs with a fuzzy select around a shape on a light coloured background. A border of semi-transparent light pixels (anti-aliasing) remains. The fix for this is shrink the selection to exclude the border before copy / paste.
How did you make your initial selection and from where ?
From what is given:
I made a temporary duplicate layer so I can see the edge https://i.imgur.com/8s7V5x4.jpg
Into the original layer with the selection https://i.imgur.com/7z29Tq0.jpg
Copy / paste back in. https://i.imgur.com/3xF4Etp.jpg - but dark background on dark background so any stray pixels not showing
If you give a few more details then you will get a better answer
There is also this advice https://www.gimp-forum.net/Thread-Background-removal-or-replacement-on-text-logos-and-other-computer-graphics
RE: White lines around cut out layers - adam - 05-20-2022
Hi Rich,
Sorry if I was not completely clear, this seems to only happen on some images and I am not sure why, hence the question.
My workflow for this image was as follows ( a workflow I use a lot):
Open --> use the paths tool create a path --> paths to selection --> cut --> paste as new layer in place
Expected result - same visually looking image (just one part or more is on another layer)
Actual result - the cut out and pasted in place parts have white borders around.
I wasn't using the fuzzy select tool in this occassion. I do get fuzzy borders with that tool but I clean them up, I was not expecting these fuzzy edges with the simple cut and paste commands, or is this to be expected? I hope the above makes more sense?
----
I am not sure what you are doing in your sequence, what is the duplicate layer and the dark background on dark background parts doing? This is not a workflow that I have used before.
The background colour swap thing is useful tip , thank you! Not sure how that would work for this workflow though.
RE: White lines around cut out layers - sallyanne - 05-20-2022
Make sure your image has an alpha channel before feathering
RE: White lines around cut out layers - rich2005 - 05-20-2022
@adam
You should have no problem with your workflow. It might be the copy-cut that is the problem. Like sallyanne says give the image an alpha channel and I advise not a cut but a copy.
Edit: It is the cut that is the issue, because the layer has no alpha channel (transparency) when you cut, the semi-transparent border pixels take the background colour, white but could be whatever colour is set. The pasted back-in-place edge is semi-transparent so the overlap shows white-ish.
Using a path is a great way to get your selection. Using your 'original' I get this
Sorry, all the gory detail, so 5 minute duration. Have a look and see where we differ.
RE: White lines around cut out layers - adam - 05-23-2022
@rich2005 @sallyanne
Super awesome! Thank you for all your help! I am blown away to have a whole video explaining the issue! I can see now that the issue is cutting from an non-alpha channel image. I can now adjust work flow to avoid this.
