09-14-2020, 08:01 AM
All depends on the image and how much you want to 'stretch' a section to increase the height.
Shown using Gimp 2.8 ( 2.10 is similar except plugins might be updated) Some possibilities.
General preliminary: Add transparency Layer -> Transparency -> Add Alpha channel Increase the height of the canvas Image -> Canvas size
1) Resynthesizer + heal transparency plugins https://i.imgur.com/WkR0vZd.jpg
Apply the heal transparency filter to fill the empty space with image pixels. When a bit tight on space do in small stages.
Link to the resynthesizer plugin here: https://www.gimp-forum.net/Thread-Resynt...or-Windows
2) Multiple copy-paste https://i.imgur.com/7Q5PGUK.jpg
Take a strip selection, copy -> paste -> flip -> move This ensures that the edge pixels match. If you repeat paste -> flip, you can fill the space with a concertina effect. Might be ok depending on the image.
3) The liquid rescale plugin. http://liquidrescale.wikidot.com/ https://i.imgur.com/1VYNIRH.jpg
Again depending on image, apply in increments to avoid distorting the original
Bound to be other ways, someone might come up with something.
Shown using Gimp 2.8 ( 2.10 is similar except plugins might be updated) Some possibilities.
General preliminary: Add transparency Layer -> Transparency -> Add Alpha channel Increase the height of the canvas Image -> Canvas size
1) Resynthesizer + heal transparency plugins https://i.imgur.com/WkR0vZd.jpg
Apply the heal transparency filter to fill the empty space with image pixels. When a bit tight on space do in small stages.
Link to the resynthesizer plugin here: https://www.gimp-forum.net/Thread-Resynt...or-Windows
2) Multiple copy-paste https://i.imgur.com/7Q5PGUK.jpg
Take a strip selection, copy -> paste -> flip -> move This ensures that the edge pixels match. If you repeat paste -> flip, you can fill the space with a concertina effect. Might be ok depending on the image.
3) The liquid rescale plugin. http://liquidrescale.wikidot.com/ https://i.imgur.com/1VYNIRH.jpg
Again depending on image, apply in increments to avoid distorting the original
Bound to be other ways, someone might come up with something.