Image enhancement by spline interpolation and adaptive power spectrum cut-off of filtered images

This paper presents a new approach to enhance resolution of the image using interpolation on filtered image. It is evident that low frequency filtered image smoothes the image, though the high frequency filtered image presents sharp change in intensity of the image. Interpolating high frequency filtered image and combining with interpolated low frequency image preserves edge information. Cubic spline interpolation is used to interpolate high and low frequency filtered image. Moreover the cut-off frequency of filter is decided on the basis of power spectrum for better result. The proposed method is tested on satellite and medical images. The quantitative and subjective results has established superiority of the proposed scheme over linear and nonlinear interpolation methods.