Using optimal rendering to visually mask defective subpixels

Visually Optimal Rendering is a subpixel-based method of rendering imagery on a colour matrix display that jointly maximises displayed resolution and minimises attendant colour aliasing. This paper first outlines the Constrained Optimisation framework we have developed for the design of Optimal Rendering Filters. This framework takes into account the subpixel geometry and colour primaries of the panel, and the luminance and chrominance Contrast Sensitivity Functions of the visual system. The resulting Optimal Rendering Filter Matrix can be designed for any regular 2D lattice of subpixels, including multi-primary lattices. The mathematical machinery of Visually Optimal Rendering is then applied to the problem of visually masking defective subpixels on the display. The rendering filters that result are able to reduce black subpixel defects for any primary colour to the point of near invisibility at normal viewing distances. These filters have the interesting property of being shift-varying. This property allows the Optimal Filter Array to intelligently modify the values surrounding a defect in a way that takes advantage of the visual system's differing sensitivities to luminance and chrominance detail in order to best mask a defect.