Add a solid border without changing the overall size - Printable Version +- Gimp-Forum.net (https://www.gimp-forum.net) +-- Forum: GIMP (https://www.gimp-forum.net/Forum-GIMP) +--- Forum: General questions (https://www.gimp-forum.net/Forum-General-questions) +--- Thread: Add a solid border without changing the overall size (/Thread-Add-a-solid-border-without-changing-the-overall-size)

Add a solid border without changing the overall size - Summoner99 - 05-09-2020 I'm fairly new to Gimp, so this might be a straightforward answer. I have a collection of images that are a solid color with transparent backgrounds. https://imgur.com/a/mw6jj6x This is a crude example. The left arrow is the type of image I have where Green is the solid color and White is transparent. My goal is to add borders like the red in the example.  The middle adds a single layer of pixels outside of the original, overwriting some transparency. The right replaces the outermost layer of pixels with a new color without replacing any transparent pixels. Clearly the optimal solution would work for any number of pixels. The images are not simple polygons so I can't just use a specialized rectangle/circle/etc drawing tool. I created the example by using the pencil tool and manually changing pixels to red. This is not feasible for larger images. Also avoiding some sort of smoothing would be nice. I want the border to be a solid color. Any solutions that involve smoothing are still acceptable. Thanks for any and all advice! RE: Add a solid border without changing the overall size - Ofnuts - 05-09-2020 Layer>Transparency>Alpha to selection, and do something with the outline of that selection: Select>Border and bucket-fill: easiest, but you don't get sharp angles Edit>Stroke selection (in Line mode, because using a brush will also prevent sharp angles) Select>To path, Select>None, Edit>Stroke path: somewhat cleaner than Edit>Stroke selection All these techniques create an outline that straddles the current border of your object. You can improve on them to keep the very same outline (the painting is done only inside) or to keep the current shape (painting is done outside) but there are small details that need to be taken in account for a correct result. The  "Stroke path" method (in the three modes:  over, inside, outside) is used by my ofn-outline-layer script that you will find here. RE: Add a solid border without changing the overall size - rich2005 - 05-09-2020 Using standard Gimp tools. border around:  Add a layer under the icon Color select the icon Grow the selection x pixels Fill layer under icon Turn selection off merge layers border inside: Toggle alpha lock on Color select icon Shrink the selection x pixels Invert the selection Fill the selection Turn selection off Toggle alpha lock off Example: 2 minutes https://youtu.be/YbS9dFhGOoQ