[ITK] Image Quartiles

[Imre Goretzki]

Hey guys,

I'd like to ask, if there already is a filter, that calculates the lower 
and upper quartile of an (3D) image.
I know there is the StatisticsImageFilter

http://itk.org/Wiki/ITK/Examples/Statistics/StatisticsImageFilter

but this filter only returns the mean, min, max and the standard deviation.

Thanks in advance.
Imre