I have a map with yellow roads, green terrain, black borders and blue water. I want to make my roads wider.
My roads are yellow. Is there a way to select every yellow pixel in my image and add an adjacent yellow pixel to everything in the image with that color?
A zoomed in view of the larger map I am dealing with is attached.
Use Select > Color Range to select all the yellow pixels. Press Q to enter Quick Mask mode. With the Quick Mask channel active, run Filter > Other > Maximum. Press Q to return to Standard Mode. Set the Foreground color to Yellow, and fill, then deselect.
This is sort of a brute-force way, but you could add refinements like extra layers with various blending mode and such
Unfortunately no image accompanied your post so I have to assume that you can make a selection of the yellow road. In that case, make that yellow your Foreground Color. Then make a Selection of the road. With the marching ants showing, choose Select > Modify > Expand and enter 1 or more pixels to expand the Selection. Follow that with Edit > Fill and fill with the Foreground color.
Could you please post (a part of) the image in question?
It must have failed to attach. Thank you all for the suggestions. I will give it a try tomorrow.
Please post the actual image (or part of it), not a rotated and therefore damaged version.
Edit: It actually looks like a photograph of the screen …