InverseRestore Method

Description:

Performs image restoration using inverse filtering in the frequency domain. The idea is to deconvolve PSF from the blurred data to extract the original image.

The deconvolution involves dividing the Fourier transform of the blurred image by the Fourier transform of PSF. If the transform of PSF has very small values, then the division result from those small values could easily dominate the entire result. The approach used to get around this issue is to limit the smallest value of the transform of PSF, thus we require a threshold value, dThreshold, to be passed in as a parameter. Ideally, this value will be just above the noise level in the image. This method places zeros in the output for those data points where the magnitude of PSF transform is below the threshold. In this respect, InverseRestore is actually an implementation of a pseudo-inverse filter.

This method takes into account the ROI settings of pPage object, that are accessible via the IGPage Object.ROI property. By default ROI is set to the entire image.

Syntax:

      InverseRestore(pPage As IGPage, PSFVector As IGDataArray,
dThreshold As double)

Parameters:

Name	Description
pPage	IGPage Object to be restored.
PSFVector	Double array which represents the Point Spread Function (PSF) in spatial domain, also called Degradation Function.
dThreshold	The threshold parameter for Inverse Filtering.

Return Value:

None

Bits Per Pixel:

8bit grayscale images with one channel

Sample:

FreqIP