Optimal prefiltering for improved image interpolation

In this paper we derive an optimal (MMSE) prefilter for image interpolation. This derivation is based upon a model of the sensor used to capture the image. To employ this model, we restate the interpolation problem in an intuitive, reconstruction-like fashion. Using a simple CCD sensor model, an example prefilter is derived. Simulations with this prefilter are performed using linear and cubic interpolation as well as an ad hoc, directional interpolation scheme. Quantitative and subjective results indicate that prefiltering generally improves the quality of the interpolated images.