An Optimized Interpolation Algorithm for Bayer Pattern CFA Images based on Gradient

Digital cameras acquire images by using color filter array, each pixel contains information of only one color channel. In order to get the rest color channel information, interpolation of the image is needed. The interpolation algorithm directly affects the image quality, and most of the current algorithms have defects in some way. Some interpolation algorithms are very simple, thus causing image distortion, some perform well but are too complex to implement. This paper proposes an improved interpolation algorithm for the most widely used color filter array, Bayer array. The proposed algorithm can achieve both interpolation efficiency and interpolation effect. Based on bilinear interpolation algorithm and edge oriented interpolation algorithm, applying gradient method and color difference rule, the proposed algorithm makes full use of the correlation between color channels, and the algorithm doesn’t have great complexity. The experimental results show that the improved interpolation algorithm performs well.