CStats:GeometricMean

The GeomMean method computes the mean value inside a rectangular region of the image using the geometric mean to assign lower weight to deviant pixels. The rectangle and image must have been previously initialized for the CStats object.

Syntax

nMean = CStats:GeoMean()

On success, returns the geometric mean value as a number.

On failure, returns 0.

Remarks

This method calculates the mean value based on the geometric mean of the sample pixels. This results in pixels being assigned weight that is inversely proportional to their value-distance from the mean. No rejection ("clipping") is performed.

Example

Suppose a CImage named I and a CRect named R exist. The following script fragment returns the geometric mean value inside a rectangle on the image:

S = CStats:new()	-- create a CStats object
S:Init( I, R )	-- specify CImage and CRect to measure
nVal = S:GeoMean()	-- return the geometric mean value
Printf("mean=%lg\n", nVal)	-- list the result
S:delete()	-- when done with S, remove it from memory