Fractional Partial Differential Equation: Fractional Total Variation and Fractional Steepest Descent Approach-Based Multiscale Denoising Model for Texture Image

Figure 5

Denoising effects of texture-rich metallographic image of iron ball. (a) Original clean image, (b) noisy image (adds white Gaussian noise to the original clean image, PSNR = 13.6872), (c) partial enlarged details of 1/4 party of (a) red box, (d) denoised image of bilateral filtering denoising [88, 89, 93], (e) residual plot of bilateral filtering denoising, (f) partial enlarged details of 1/4 party of (d) red box, (g) denoised image of wavelet denoising [92, 93], (h) residual plot of wavelet denoising, (i) partial enlarged details of 1/4 party of (g) red box, (j) denoised image of NLMF denoising [94, 95], (k) residual plot of NLMF denoising, (l) partial enlarged details of 1/4 party of (j) red box, (m) denoised image of FDM denoising (𝑣₁=1.75, 𝑣₂=2.25, 𝑣₃=1.05, Δ𝑡=10⁻¹⁰), (n) residual plot of FDM denoising, (o) partial enlarged details of 1/4 party of (m) red box, (p) denoised Image of FDM denoising (𝑣₁=2.25, 𝑣₂=2.5, 𝑣₃=1.25, Δ𝑡=10⁻¹⁰), (q) residual plot of FDM denoising, (r) partial enlarged details of 1/4 party of (p) red box.

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