I have a bunch of images whose size is 750×1000 pixels. I wanted to make them 1000×1000 without risking stretching the depicted object so I have enlarged the canvas and centered the original image. But how will I fill the canvas with the image’s background?
If have a more complex image (e.g. photo) instead of a single color, you might want to check the heal selection tool.
It does an incredible job filling up unwanted/empty parts with a surrounding ‘texture’.
Filters → Enhance → Heal Selection…
see illustrations https://patdavid.net/2012/08/getting-around-in-gimp-heal-selection.html
Source : Link , Question Author : vpapakir , Answer Author : Lennert