Satellite Image Resolution Enhancement Using Dyadic-integer Coefficients Based Bi-orthogonal Wavelet Filters

The acquisition of high satellite Imagery becomes difficult due to the instrument limitation and imperfect imaging optics. Low spatial resolution satellite images consist a lot of mixed pixels which degrade the detection and recognition performance in civil and military applications. In this paper, a satellite image resolution enhancement using Dyadic-Integer coefficients based bi-orthogonal wavelet filters is proposed. Dyadic-integer-coefficient based wavelet filters are derived from the construction of a half-band polynomial. The splitting approach is used to develop the integer-coefficient based half-band polynomial. The possibility of these dyadic-integer coefficients based wavelet filters is explored in the field of image enhancement using sub-pixel image registration. The two-resolution frames are registered at a specific shift from one another to restore the resolution lost by the sensors. The discrete wavelet transform (DWT) obtained from the designed coefficients is applied on these two low-resolution images to obtain the high resolution image. The proposed method has been tested on satellite images. The quantitative (peak signal-to-noise ratio and root mean square error) and visual results show the superiority of the proposed technique over the conventional and state-of-art image resolution enhancement techniques.