I was trying to submit an app to the Windows Phone app store. Here all pixels need to be white (#FFFFFF) or transparant (#FF####).

I had a black logo on a white background. To make the background transparant and the foreground white I used Gimp. First I made the background transparant using the magic wand and changing color to alpha. Then I inverted the remaining colors. Unfortunately the images did not get accepted in the Windows Phone app store because not all pixels were white or transparant.

How can non-white or transparant pixels in Gimp be converted to white?

1 Answer 1


Are you sure you need the GIF format? PNG would allow smooth edges with transparency.

To edit the output colors you should first set your color mode to Indexed (Image > Mode > Indexed). For the conversion select Use black and white (1-bit) palette

Then you can edit the color table (Window > Dockable Dialogues > Colormap). Just doubleclick the black color and set it to white.

Edit: For a PNG you can use Colorize (Colors > Colorize) where you can set Lightness to +100 to make everything white. This will keep transparency intact.

  • Hi AAGD, welcome to GDSE and thanks for your answer. If you have any questions, please see the help center or ping one of us in the Graphic Design Chat. Keep contributing and enjoy the site!
    – Vincent
    Commented Oct 22, 2015 at 13:22
  • The lightness trick did work perfectly for my PNG icon, didn't think about that one!
    – FlorianT
    Commented Nov 7, 2017 at 20:11
  • Lightnessadjustment is the quick and easy way for PNG - thanks! Commented Jan 4, 2018 at 16:03
  • Lightness worked for me too! I also had to make sure that the entire canvas was selected. Commented Sep 11, 2019 at 14:09

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.