GIMP - new version 2.8.6 Rev 2
is a versatile graphics manipulation package.
The GIMP (GNU Image Manipulation Program) is a freely distributed program for such tasks as photo retouching, image composition and image authoring.
It has many capabilities.
It can be used as a simple paint program, an expert quality photo retouching program, an online batch processing system, a mass production image renderer, an image format converter, etc.
GIMP portable download