The above images r(x,y) consist of three components
(x,y) * r(x,y) accounts for the blurring by the throughput response r(x,y) (see result ),
nar(x,y) accounts for the aliasing caused by the insufficient sampling that occurs because the SFR extends beyond the sampling passband , and npr(x,y) accounts for the photodetector noise.
The extraneous periodic structure that aliasing produces in the images of the resolution wedges is commonly referred to as Moire pattern. The corresponding distortion in the images of the random polygons, however, emerges more subtle as jagged (or staircase) edges. If these images are displayed at a small format, then the jagged edges could not be resolved by the observer and would appear to be the result of blurring instead of aliasing. Aliasing has therefore often been overlooked as a significant source of image degradation.
The images produced by Wiener restorations, such as the ones shown above, normally have a high resolution and sharpness. However, it is often desirable to combine this restoration with an enhancement filter that gives the user some control over the trade-off among fidelity, resolution, sharpness and clarity. The images shown below represent such enhancement for the above images.