Quadratic Taylor Approximation Demosaicking System Using Post-Processing for Zipper Artifact Removal

Abstract

In this paper, we propose a new demosaicking system that uses post-processing technique to remove zipper artifacts that are primarily caused by improper interpolation in a quincunx-sampled green plane. We use a high-order approximation to predict accurate pixel values in the weighted average-based green channel interpolation. We also perform prediction using a color difference model in the red and blue channel interpolation process. As a well-designed demosaicking system too cannot prevent the occurrence of ON-OFF pattern artifacts and the resulting false colors, we propose post-processing for zipper artifact detection and removal to improve the demosaicked image. After performing the just noticeable difference model-based zipper artifact detection in the luminance image of the demosaicked image, the clamping-based zipper artifact removal process is performed in the red, green, and blue planes. Experimental results demonstrate that the proposed demosaicking system improves both the objective and subjective image qualities compared to the conventional state-of-the-art demosaicking algorithms.