CImage:PolyFitDiv

CImage:PolyFitDiv

The PolyFitDiv method fits a 2-D polynomial of intensity versus position and divides it into the image.

Syntax

bResult = CImage:PolyFitDiv( ct, rt, bConserve=true, CRect=nil )

ct is the number of column fit terms, 1 to 10.
rt is the number of row direction fit terms, 1 to 10.
bConserve preserves the central sigma level, defaults to true.
CRect defines a CRect region to be excluded from the fit. If omitted or nil, the entire image is fit.
On success, this method returns true.
On failure, this method returns false.

Remarks

This method fits a polynomial to the image intensity as a function of (x,y) position. The polynomial is then divided into every pixel as a function of position.

When applying this method to integer data types, the resulting image will have very low signal to noise ratio because all the mathematical significance will be truncated to values near 1. To avoid this problem, Mira automatically promotes the data type to float or double as part of the processing.

Example

The following script fragment loads an image from file sPath and divides a 3 x 2 term polynomial into it. A dark defect exists in the region (300:350, 200:300). This is omitted from the fit by specifying the region to a CRect R:

I = CImage:new()	-- create a new CImage
I:Open( sPath )	-- load the image
R = CRect:new(300,350,200,300)	-- omit a dark defect from the fit
I:PolyFitDiv(3,2,true,R)	-- perform the operation on image I
I:Display()
I:delete()
R:delete()