How do I fill non contiguous areas of the same colour

[leamphil]

How do I fill all the areas (non contiguous ones) of the same colour with one click ? 
... without having to click on each non contiguous area

Regards,
Leamphil

[PixLab]

An example of what you want to fill would be nice.

Other than that, with the bucket tool you got plenty options the way you want to fill
> more about it https://docs.gimp.org/en/gimp-tool-bucket-fill.html all options explained.

   

Colors > Colorize... could be an alternative inside a rough selection depending your image and options given to colorize
Also Colors > Map > Color exchange... could be the one you need

But an excerpt of your image is needed for us to see what you need, or the fastest way to do it

[leamphil]

Here is an example - I want to remove the postage stamp from the image, leaving just the cancellation.

   

So I'm looking for a bucket fill on all the orange areas.

[denzjos]

Something like this :

   

[leamphil]

(07-10-2023, 03:37 PM)denzjos Wrote: Something like this :

Very good, worked well on another postmark I had.

Sometimes it would also be helpful to be able to fill all the areas of a particular colour - is that possible too ?

[Ofnuts]

(07-10-2023, 04:22 PM)leamphil Wrote:

(07-10-2023, 03:37 PM)denzjos Wrote: Something like this :

Very good, worked well on another postmark I had.

Sometimes it would also be helpful to be able to fill all the areas of a particular colour - is that possible too ?

Do a "Select by color", click on a pixel of the desired color to select all pixels with the same (or near the same, depending on threshold) then bucket fill the selection.

Howeverr... on your stamps this may not work too well because what looks like the same color all over is made of rather different pixels. So you have to play tricks... For instance, duplicate the layer, and blur it a bit to make the color more uniform, make a selection from this and use that selection to paint the initial layer.  The Color selector can also use more advanced criteria than just the color (aka Comoiste): any of the RGB channels, hue, saturation, luminosity....

Plus some pictures are very easy: open the Channels list for your picture, and you can see that the red channel is already pretty much the picture you want:

   

You just have to drag it to the toolbox to copy it as a new image, or to the canvas to obtain it as a new layer.

[leamphil]

Thanks very much - I'll have to do a bit of practice at this I think !