Background images used in the examples were extracted from:

http://good-wallpapers.com/art/4121
http://files.all-free-download.com/downloadfiles/wallpapers/1920_1200_widescreen/old_farm_wallpaper_landscape_nature_wallpaper_1920_1200_widescreen_1439.jpg
http://www.hdwallpaperstop.com/wp-content/uploads/2013/05/Beautiful-Landscape-Pictures-of-nature.jpg
http://duggal.com/connect/wp-content/uploads/2013/06/Landscape-Nature-for-Wallpaper-Dekstop-.jpg
http://www.imgbase.info/images/safe-wallpapers/digital_art/3d_landscape/9659_3d_landscape.jpg