CImage:ApplyPixelMask

The ApplyPixelMask method repairs point defects identified by locations stored in a pixel mask file. This is effective for repairing point defects as well as single row and single column artifacts.

Syntax

bResult = CImage:ApplyPixelMask( nMethod, sMaskFile, CRect=nil )

nMethod is a number corresponding to the repair method (see Remarks).
sMaskFile is the name of the text file containing the pixel mask.
The rectangular region to repair is specified by a CRect, with 1-based coordinates. If omitted, the entire image is repaired.

On success, this method returns true.
On failure, false is returned.

Remarks

This method replaces point values using a statistic computed from pixels in the neighborhood. The neighborhood method is described in the table below.

Pixel Mask Neighborhood Methods
Method	Description
1	Replaces the pixel by the mean value from its 4 nearest neighbors.
2	Replaces the pixel by the median value from its 4 nearest neighbors.
3	Replaces the pixel by the median value from its 8 nearest neighbors. Use this method for repairing 1 pixel wide line defects.

Point locations in need of repair are identified by pixel coordinates in a Pixel Mask File. A related pixel repair method is SetMaskedValue which replaces pixels with a specific value rather than a computed neighborhood value.

Example

Assume that a pixel mask file named sMaskFile exists. The following script fragment repairs point values in the image in a file named sPath using defect coordinates from the pixel mask file. Points in the central 50% of the image are repaired by replacing them with the median of their 8 nearest neighbors:


I = CImage:new()	-- Create a CImage
I:Open( sPath )	-- Open the image from sPath.
w = I:Cols() ; h = I:Rows()	-- get image width and height
R = CRect:new()	-- create a rectangle
R:Set( 0.25w, 0.75w, 0.25h, 0.25h ) )	-- central 50% of columns and rows
I:ApplyPixelMask( 3, sMaskFile, R )	-- apply the pixel mask
I:Save()	-- save the image
I:delete()	-- delete the CImage from memory
R:delete()	-- delete the CRect from memory