
Red enhance method 1
Duplicate original image
On the main GIMP toolbar, open the layers dialogue
File » Dialogues » Layers
In the layers dialogue click Duplicate
and create 3 copies of your image.
Download GIMP 

On the main GIMP toolbar, open the layers dialogue
File » Dialogues » Layers
In the layers dialogue click Duplicate
and create 3 copies of your image.