CImCombine:Mean

CImCombine:Mean

The Mean method merges the pixel values using the mean statistic at each location.

Syntax

CImage = CImCombine:Mean( CImageSet )

CImageSet contains the collection of images to be combined.
CImage is a new image created by this method.
On success, this method returns a new CImage.
On failure, this method returns nil.

Remarks

Each pixel in the output image is the mean of values at the same location in all the images of the CImageSet. The mean value maximizes the signal-to-noise ration of the resulting image when the images differ by random noise and contain no outlying "bad" pixels. If the images are not free of bad pixels, consider using the Median or a clipping method to reject the outliers. Normalization is used to remove offsets between the images prior to combining.

Example

Suppose a CImageSet named S exists. The following script fragment combines the images by the Mean method after normalizing their luminance by the median statistic computed inside the central 10% of the image:

C = CImCombine:new()	-- create a CImCombine object
R = CRect:new(10,50,10,50)	-- central 10% of the image
C:SetRelRect( R )	-- specify CImage and CRect to measure
C:SetNormStat("median")	-- use the median as the normalization statistic
C:SetNormMethod("scale")	-- scale to normalize the image set
I = C:Mean( S )	-- combine the image set and return a new image
I:Display()	-- show the new image
C:delete()	-- when done with S, remove it from memory