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Re: [LUG] a GIMP problem

 

On Mon, 14 Feb 2005 15:56:13 +0000
Tony Sumner wrote:

One should not underestimate the power of GIMP but what I want to do
is simple and I cannot, even after studying the handbook for hours,
see how to do it. I have an image that was sent to me as a b/w gif
file and I want to convert it to a RGB file in colour. I have exported
the original file and saved it so that it says under the window that
it is RGB (previously it was indexed) but I still can't do a colour
exchange on it because the colour exchange filter is grayed out. It
seems to want to remain a two colour image. The image is some oak leaves
in black on a white ground (it's not unrelated to the National Trust)
and I want eventually to end with the oak leaves white on a green ground.
How do I get the colour exchange function to switch on?

Tony Sumner

Two simple methods - I'm sure there are more complex ways of doing this that will 
give you finer control, but these seem to work nicely.

Ok, load up the original image.

Method 1:
---------
Make sure the colour map dialogue is showing.
Image --> Mode --> RGB
Click on the fill (spilling bucket) icon.
Use the colour map dialogue to change the forecolour to your chosen shade of green.
Click on the background.
Use the colour map dialogue to change the background colour to white.
Click on the leaves.

Method 2:
---------
Make sure the colour map dialogue is showing.
Image --> Mode --> RGB
Layers --> Colours --> Invert
Use the colour map dialogue to change the forecolour to your chosen shade of green.
Click on the background.

Grant.
-- 
Artificial intelligence is no match for nuratal stidutipy.

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