Usage

 winstat [-w rows<integer> [cols<integer>]]
    [-lm | -gm | -nm]
    [-var | -sd] [imagefile]

-w

Window size

-lm

Use local mean when computing the variance (default)

-gm

use global mean...

-nm

Don't use mean (assume that the mean is zero)

-var

Calculate windowed variance (default)

-sd

Calculate windowed standard deviation