“…For denoising in spatial domain, linear and non-linear filters [5,6,7] anisotropic diffusion [8,9] and total variation methods [10], dictionary learning method [11,12], bilateral and non-local means (NLM) filters [13], Neural Networks [14,15] and deep learning algorithms [16,17,18] have been used. For transform domain filtering, Wavelet based denoising [19,20], fourier based denoising [21,22], curvelet based denosinig [23,24], threshold estimation [25] and shrinkage rules [26,27] have been used.…”