An Image Denoising Method with Enhancement of the Directional Features Based on Wavelet and SVD Transforms

Figure 4

(a) The original image; (b) the noised image (); (c) the singular value curve of the horizontal high-frequency image; (d) the relation of the singular value number and PSNR; (e-1) the one-layer horizontal high-frequency image using the SVD denoising; (e-2) the one-layer vertical high-frequency image using the SVD denoising; (e-3) the one-layer diagonal high-frequency image with rotation of 45 degrees; (e-4) the denoised image of (e-3) using the SVD denoising; (e-5) the image of (e-4) with rotation restore; (e-6) the edge of the one-layer horizontal high-frequency image; (e-7) the edge of the one-layer vertical high-frequency image; (e-8) the edge of the one-layer diagonal high-frequency image; (e-9) the one-layer horizontal high-frequency image after the fusion; (e-10) the one-layer vertical high-frequency image after fusion; (e-11) the one-layer diagonal high-frequency image after fusion; (f-1) the denoised image using the method in this paper (db3 wavelet); (f-2) the denoising image using the method in this paper (sym3 wavelet); (g-1) the denoised image based on the traditional wavelet hard threshold (db3 wavelet); (g-2) the denoised image based on the traditional wavelet hard threshold (sym3 wavelet); (h-1) the denoised image based on the traditional wavelet soft threshold (db3 wavelet); (h-2) the denoised image based on the traditional wavelet soft threshold (sym3 wavelet); (i-1) the denoised image using the method in [3] for hard thresholding (db3 wavelet); (i-2) the denoised image using the method in [3] for hard thresholding (sym3 wavelet); (j-1) the denoised image using the method in [3] for soft thresholding (db3 wavelet); (j-2) the denoised image using the method in [3] for soft thresholding (sym3 wavelet); (k) the denoised image based on traditional SVD; (l) the denoised image using the method in this paper with the two-layer wavelet decomposition (db3 wavelet); (m) the denoised image using the method in this paper with the three-layer wavelet decomposition (db3 wavelet); (n) the PSNR results for different methods; (o) the PSNR results with 1~3-layer wavelet decomposition (db3 wavelet); (p-1) the PSNR with three denoising methods (, db3 wavelet); (p-2) the PSNR with three denoising methods (, sym3 wavelet); (q-1) the PSNR with three denoising methods (, db3 wavelet); (q-2) the PSNR with three denoising methods (, sym3 wavelet); (r-1) the PSNR with three denoising methods (, db3 wavelet); (r-2) the PSNR with three denoising methods (, sym3 wavelet).