Using pixel shader 2.0 more complex operations can be performed on World Wind texture tiles.
The spectral contrast stretch operations involve converting from RGB to HSI space and adjusting the intensity with a multiplier and offset, then converting back to RGB. This involves a quite long and complex pixel shader. The results are shown here.
Spatial enhancements such as blur,sharpen or any other convolution oriented operations involve look up using texture coordinates and are dependent on texture size. I have implemented blur and sharpen, hopefully arbitrary 3x3 convolutions soon with parameterization of the matrix. Notice how the jpeg artifacts are affected by sharpen and blur.