Novel 2-D MMSE subpixel-based image down-sampling for matrix displays

Subpixel-based down-sampling is a method that can potentially improve the apparent resolution of a down-scaled image by controlling individual subpixels rather than pixels. However, the increased luminance resolution often comes at the price of chrominance distortion. In this paper, we propose a new subpixel-based down-sampling scheme for which we design a two-dimensional image reconstruction model. Then, we formulate subpixel-based down-sampling as a MMSE problem and derive the optimal solution called MMSESD. To compare the performance of subpixel-based down-sampling methods, we propose novel objective measures for the apparent luminance resolution and chrominance distortion. Simulation results show that MMSE-SD can give sharper images compared with the conventional down-sampling methods, with little color fringing artifacts.