Equalise is a Photoshop-compatible plug-in. It works in a similar way to the IMAGE/MAP/EQUALISE menu item in Photoshop, but allows you to use neighbourhood equalisation.
In normal equalisation, each pixel's intensity is adjusted according to the levels of all the pixels in the image or selection.
In neighbourhood equalisation, each pixel is adjusted according to the levels of its neighbours. You define the size of the neighbourhood in the filter dialog. The larger the neighbourhood you use, the more similar the result will be to ordinary equalisation.
The result of this is to brighten areas of shadow, and increase detail in areas of similar tone. See the demos for examples of the effect.
The filter is for PowerMacs. I have tested it on a 7100/66 with Photoshop 2.5.1. Even on a Powermac, the process is very slow, especially with large neighbourhoods, so try it on a smaller area first.
If you find any bugs, have any suggestions, or find it useful, drop me a note:
