Hi,

the Color Exchange tool doesn't work well for me, too. But there's an easier way:
1. Use the Select by Color tool to select the red areas. If not everything is selected at the first click, increase the Threshold value in the dialog.
2. Fill the selected area with plain black either with the Bucket Fill tool or by dragging it from the Foreground/Background color swatch in the toolbox. (If your foreground or background color is not black, then press 'd' first).

Kind regards,

Sven

On 12/11/2013 09:51 PM, scl wrote:

Hi,

the Color Exchange tool doesn't work well for me, too. But there's an easier way:
1. Use the Select by Color tool to select the red areas. If not everything is selected at the first click, increase the Threshold value in the dialog.
2. Fill the selected area with plain black either with the Bucket Fill tool or by dragging it from the Foreground/Background color swatch in the toolbox. (If your foreground or background color is not black, then press 'd' first).

Select by color (and its brother the fuzzy select tool) don't work for this because they always fully select the pixels or completely ignore them. And the text is surrounded by anti-aliasing pixels that are a blend of the two colors and should be only partly repainted, Otherwise you obtain a faint red rim (anti-aliasing pixels not selected and not repainted) or a jagged text ((anti-aliasing pixels selected and completely obliterated with the new color).

The right way to do it is to make the background transparent with either color-2-alpha or painting in "color erase" mode (this will make the anti-aliasing pixels partially transparent as needed), then give the new color to the background either by adding a layer filled with the background color below the current layer, or by painting the current layer in "behind" mode.

This said this image had a formed life as a badly compressed JPEG, so it's not really worth editing.You'll find much better versions of that image using Google images.