Table 2.

Mathematic description of the most important identified features of Run Length approach.

Run-Length Features	Formula
SRE	$\frac{1}{N}{\displaystyle \sum _{i=1}^{N_g}}{\displaystyle \sum _{j=1}^{N_r}}\frac{p\left(i,j\right)}{j^2}$
RLNU	$\frac{1}{N^2}{\displaystyle \sum _{i=1}^{N_g}}{\left({\displaystyle \sum _{j=1}^{N_r}}p\left(i,j\right)\right)}^2$
LGLRE	$\frac{1}{N}{\displaystyle \sum _{i=1}^{N_g}}{\displaystyle \sum _{j=1}^{N_r}}\frac{p\left(i,j\right)}{i^2}$