Demosaicing approach based on extended color total-variation regularization

Previously we presented a TV (total variation)-based sharpening-demosaicing method. Our previous method interpolates color signals effectively while preserving sharp color edges, without producing ringing artifacts along the edges. However, since our previous method applies the TV regularization separately to each primary color channel, it sometimes produces color artifacts along sharp color edges. To remedy the drawback, we introduce the TV regularization of color differences and color sums into our previous method. Unlike our previous method, our new method jointly interpolates the three primary color channels. We compare demosaicing performance of our new method with the state-of-the- art demosaicing methods. In the evaluations, we consider a noise- free case and a noisy case. For both cases our new method achieves the best performance, and for the noisy case our new method considerably outperforms the state-of-the-art methods.