GIMP is a free program for such photo retouching, image composition and image authoring. Essentially it's the closest thing to Photoshop you can get for free.
Free
Open Source
Mac OS X
Windows
Linux
BSD
Haiku
Xfce
AmigaOS
GIMP is a freely distributed program for such tasks as photo retouching, image composition and image authoring. 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, and more.
Available also as portable app: http://portableapps.com/apps/graphics_pictures/gimp_portable
Adobe Photoshop Elements combines power and simplicity so you can make ordinary photos extraordinary; tell engaging stories in beautiful, personalized creations for print and the web; and easily find and view all your photos.
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