You might want to try using color to alpha.
Colors > Color to Alpha
To fine tune it you can use the curves tool.
Something like this maybe.
On Sun, Dec 28, 2014, at 06:27 AM, Chris1968 wrote:
> Hi all,
> I am planning to build a website over the coming weeks but I want to make
> custom images albeit slightly basic ones. My first image project would be
> banner for the home page for which I already have an image which I will
> to this post.
> It is a simple two colour image of a pentagram. The pentagram is black
> against a
> white background but I want to change the black to a shade of gold maybe
> and the
> background to a shade of black. Rather that editing it pixel by pixel
> there must
> be an easier way by using gimp to alter the pentagram's colour and the
> background colour.
> Any help greatly appreciated.
> * http://www.gimpusers.com/system/attachments/182/original/pentagram.jpg
> Chris1968 (via www.gimpusers.com/forums)
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