Moments  
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Menu:   Measure > Parameters  
Script:   SelectParam ("Moments")  

Select these parameters to compute the central binary moments of objects. The moments are calculated relative to the object's centroid. The following formula is used in calculations:

moments

where

µij is a central moment of an order i+j
x is a pixel's horizontal coordinate
y is a pixels's vertical coordinate
xc is a horizontal coordinate of the object's center of gravity
yc is a vertical coordinate of the object's center of gravity

The geometric interpretation of the central binary moments have a direct analogy with the mechanics of bodies. Such descriptors can be interpreted as listed below:
·µ20 horizontal centralness .  
·µ11 diagonality; indication of quadrant with respect to centroid where R has more mass.  
·µ02 vertical centralness .  
·µ30 horizontal imbalance; location of the center of gravity with respect to half horizontal extent.  
·µ21 vertical divergence; indicates the relative extent of the bottom of R compared to the top.  
·µ12 horizontal divergence; indicates the relative extent of the left of R compared to the right.  
·µ03 vertical imbalance; location of the center of gravity with respect to half vertical extent.  
Moments receives the array of the object's binary moments in calibrated units, in the order indicated above. To access a specific element of the array in the script, use the following syntax:

x= getParamValue("Moments", i)

Refer to ImageWarp Language Reference for more details.