High definition color interpolation scheme for progressive scan CCD image sensor

A color interpolation scheme for a progressive scan CCD image sensor with a RGB color filter array is required to overcome the physical limitation of the CCD image sensor and to increase the resolution of color signals. Most conventional approaches result in blurred edges and false color artifacts. In this paper, we propose an improved edge-adaptive color interpolation scheme for a progressive scan CCD image sensor. The proposed edge indicator function uses not only the within-channel correlation but also the cross-channel correlation, and reflects the edge characteristics in an image adaptively. The color components unavailable at each channel are interpolated along the edge direction, not across the edges, so that aliasing artifacts are suppressed. Furthermore, we eliminated false color artifacts resulting from the color image formation model in the edge-adaptive color interpolation scheme by adopting the switching algorithm that is based on the color edge detection. Simulation results of the proposed algorithm indicate that the improved edge-adaptive color interpolation scheme produces better quantitative and visually pleasing results than other conventional approaches.