Denoising solar radiation data using coiflet wavelets

Denoising using new thresholding method

“…The thresholding can be either soft, hard or semi-soft thresholding (Misiti et al [11]). In Karim et al [6], newthresholding value is proposed by calculating at each level of decomposition (level dependent) and the formula is given by…”

“…Since wavelet transform has the capability to orthogonalize the data and produces the sparse matrix in the transformation, then wavelet transform give better results compared to the other image processing methods such as Gaussian, Fourier transform, Hilbert-Huang transform etc. Some applications of wavelet based methods are in finance, economy and solar radiations (Karim et al [1,2,3,4,5,6] and Al-Wadi et al [7]). …”

“…Some scientific contributions are as follows: (a) We investigate the mathematical properties for the new thresholding method of Karim et al [6]. (b) In Karim et al [6] the Coiflet2 wavelets have been used meanwhile in this paper Daubechies 4 wavelets (D4) have been used.…”

“…There exists many thresholding methods such as global threshold, Minimaxi, and SURE to name a few. Karim et al [6] have proposed new thresholding method that can be used to denoised the signal or image. In this paper our main objective is to use the new thresholding method from Karim et al [6] and apply it to denoise the signals that are coming from the data of fluid flow measure of an active well (Rosli [12]).…”

“…(b) In Karim et al [6] the Coiflet2 wavelets have been used meanwhile in this paper Daubechies 4 wavelets (D4) have been used. The results are very comparable between both basis functions.…”