09-05-2017, 06:03 AM
A problem is that your image is not a good quality. The "white" background is a blotchy grey and the "black" is a blotchy charcoal. A better image will give better results.
1.
With the Colour Select tool with a Threshold of 60, select the black foreground. Looks like this:
https://imgur.com/a/0Yi9G
2.
Select > Invert
3. Edit > Clear (or press the Delete key). Looks like this:
https://imgur.com/623TOnw
4.
Select > None
5.
Set the Foreground Colour to red (or some other colour)
6.
Lock the Alpha Channel, like this:
https://imgur.com/BwIdjMf
7.
Bucket Fill the image with the set foregound colour
https://imgur.com/xY9TC7j
1.
With the Colour Select tool with a Threshold of 60, select the black foreground. Looks like this:
https://imgur.com/a/0Yi9G
2.
Select > Invert
3. Edit > Clear (or press the Delete key). Looks like this:
https://imgur.com/623TOnw
4.
Select > None
5.
Set the Foreground Colour to red (or some other colour)
6.
Lock the Alpha Channel, like this:
https://imgur.com/BwIdjMf
7.
Bucket Fill the image with the set foregound colour
https://imgur.com/xY9TC7j