NOVEL ALGORITHM FOR COLOR IMAGE DEMOSAIKCING USING LAPLACIAN MASK

Abstract

Images in any digital camera is formed with the help of a monochrome sensor, which can be either a charge-coupled device(CCD) or complementary metal oxide semi-conductor(CMOS). Interpolation is the base for any demsoaicking process. The input for interpolation is the output of the Bayer Color Filter Array which is a mosaic like lattice structure. Bayer Color Filter Array samples the channel information of R,G and B values separately assigning only one channel component per pixel. To generate a complete color image, three channel values are required. In order to find those missing samples we use interpolation. It is a technique of estimating the missing values from the discrete observed samples scattered over the space. Thus Demosaicking or De-bayering is an algorithm of finding missing values from the mosaic patterned output of the Bayer CFA. Interpolation algorithm results in few artifacts such as zippering effect in the edges. This paper introduces an algorithm for demosaicking which outperforms the existing demosaciking algorithms. The main aim of this algorithm is to accurately estimate the Green component. The standard mechanism to compare the performance is PSNR(Peak Signal to Noise Ratio) and the image dataset for comparison was Kodak image dataset. The algorithm was implemented using Matlab2009B version.