The source image for this example is a nasa map of the world showing Sea algae colour. There is no significance to this image, it just happens to be high-resolution and suitable for spherical mapping. Any Image would do for this job including a spherical panorama type image.
Image patterner is capable of mapping an image onto any rectangular mesh surface, not just a sphere (which is a special case of a rectangular mesh with double curvature). Different mapping types include planar and cylindrical as well as spherical.