...PPI is computed with the FFI index and the Lacunarity using the ToW algorithm:
PPI = FFI^(Ltw)
For FFI, please see:
https://sourceforge.net/projects/iqm-plugin-ffi/
Andronache etal. Fractal analysis for studying the evolution of forests, Chaos, Solitons & Fractals, 2016, Vol 91, 310-318.
For Tug of War Lacunarity, please see:
Reiss, Lemmerer, Hanslmeier, Ahammer Tug-of-War Lacunarity-A Novel Approach for Estimating Lacunarity. Chaos, 201611. https://doi.org/10.1063/1.4966539.
Installation instruction:
Copy newest jar file to the "Plugins" directory which should be located in the directory of your local IQM main application.
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