Woolz Image Processing
Version 1.7.5

WlzFilterNObjsValues [h] [o<output file>] [f <ref object>] [m] [r #] [i] [u] [<input objects>]
o  Output file name, default to standard out. 
f  Reference object. 
m  Use a mean filter. 
r  Use a rank filter. The parameter (range [0.01.0]) specifies the rank with: 0.0 minimum, 0.5 median and 1.0 maximum  intermediate values specify intermediate ranks. 
i  The computed reference domain is the intersection of all input object domains. 
u  The computed reference domain is the union of all input object domains. 
h  Help  print help message 
The output object is a domain object of the same type and with values of the same type of as the input objects. All input objects must be the same type and have the same grey value type. The output object has the same domain as the reference object, which may either be computed or given on the command line. The computed domain is either the intersection or union of all input objects depending on the commandline flags used. The available filter functions are mean and rank, where rank is a generalisation of minimum, median, maximum, etc.
For an output object \(O\) having values at coordinate \(w\) with \(w \in \Omega\) where \(\Omega\) is the domain of \(O\), the value at \(w\) is \(O_w = f(I_{0,w}, I_{1,w}, I_{2,w}, \cdots)\), where \(\{I_0, I_1, I_2, \cdots)\) are the input objects and \(f\) is the filter function.
cat obj2.wlz  WlzFilterNObjsValues i r 0.5 obj0.wlz obj1.wlz >out.wlzCreates a new objectct, the domain of which is the intersection of the domains of the input objects (obj0.wlz obj1.wlz obj2.wlz) and the values are the median of the input object values.