About convolution: idea is that each point of original image is smoothered into a circle-like spot.
Implementation: convolution and deconvolution is taken by using Fourier transform of original image and the response function. After this the Fourier modes multiplyed/divided in order to get Fourier mode of the final image. Fourier transform is implemented by using the Fast Fourier transform. Since our data (image) is real, it allows us to use the special method for Fast Fourier transform of a real data, which is significantly reduces computations.
Note: unfortunetly, this applet didn't work properly.
Source code: ImageProcessing.java ConvolutionFilter.java IntegerField.java SourceImage.java DisplayImage.java TransformedImage.java RestoredImage.java SourceFilter.java