Demosaicing scheme based on augmented inter‐channel correlation considering colour saturation

Abstract

Augmented colour difference gradients in the extended support region contribute to the reduction of high-frequency loss in image reconstruction via a demosaicing process. However, distant gradients must only be used for highly inter-channel correlated regions. Otherwise, the pattern grid remains, even after demosaicing. Herein, a demosaicing scheme is proposed, in which the geometric distances as well as the edge directions (as in a bilateral filter) are incorporated in order to calculate colour difference gradients weights. The inter-channel correlation is closely related to the colour saturation. Thus, the weights are adaptively adjusted according to the inter-channel correlation considering colour saturation. Experimental results show that the proposed scheme improves the results of a state-of-the-art demosaicing process.