Interpolation and zooming techniques utilizing edge-weighted adaptive filtering for color filter array

Abstract

A single sensor provided with a color filter array (CFA) format looks like a mosaic image. Each pixel in the image contains a primary color, red, green and blue, arranged alternately. Most previous interpolation and zooming techniques for CFA image utilize the gradient and the spatial information of the neighborhood color pixels around the interpolation positions. However, their characteristics of imaging color are not reconsidered. This paper proposes a new idea for CFA image interpolation and zooming techniques. The color characteristics such as the edge-weighted adaptive filtering (EWAF) and the edge modification are used to interpolate and spatially enlarge the images in order to reconstruct the original full-color images. The proposed method yields both objective and subjective image quality measurement. The experimental results show improved visualization of the images over the conventional methods. The evaluated performance is higher PSNR 1-2 dB. © 2010 Springer-Verlag.