Variational Image Restoration
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- Meryl Hensley
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1 Variational Image Restoration Yuling Jiao School of and Statistics and Mathematics ZNUFE Dec 30, 2014
2 Outline 1 1 Classical Variational Restoration Models and Algorithms 1.1 Variational Image Restoration Modeling 1.2 Algorithms for min u J (u) = F (Ku, f ) + λr(u) 2 2 Proposed Model and Algorithm 3 3 Numerical Results 3.1 Denoising 3.2 Deblurring 3.3 Inpainting (ZNFUE) Dec 30, / 118
3 1 Classical Variational Restoration Models and Algorithms
4 Variational Image Restoration Modeling f = Ku n, f Y, u X, K L(X, Y ). +, n is gaussian =, n is multiplicative n(u), n is image dependent I, Denoising convolution, Deblurring K = projection, Inpainting upsample, Zomming Dec 30, / 118
5 oringal image Dec 30, / 118
6 SNR 3.84dB,PSNR 7.89dB June 5, / 118
7 SNR 16.92dB,PSNR 29.45dB,It: 28 June 5, / 118
8 oringal image June 5, / 118
9 SNR 1.72dB,PSNR 11.99dB June 5, / 118
10 SNR 24.47dB,PSNR 35.64dB,It: 51 June 5, / 118
11 original image June 5, / 118
12 inpainted June 5, / 118
13 Variational Image Restoration Modeling Recover u from observed f by MAP: } u = arg max {P u f u u = arg min u { = arg max u { Pf u (f u)p u (u)} P f (f ) } log P f u (f u) + log P u (u) eg: restoration f = u + n with Gaussian distributed n and Gaussian prior of u, i.e., ( P f u (f u) exp f ) u 2 L 2 2σ 2 n and ( P u (u) exp ) u 2 L 2 2σ 2. u June 5, / 118
14 Variational Image Restoration Modeling Then u is recovered by min u f u 2 L 2 (Ω) + λ u H 1 (Ω) (Tikhonov regularization). So, one can recover u by the regularized variational form Then, min J (u) = F (Ku, f ) + λr(u). u proper data fitting term + proper regularization term+ fast algorithm + proper regularization parameter = good restoration June 5, / 118
15
16 Variational Image Restoration Modeling Data Fitting Term F (Ku, f ) 1 2 Ku f 2 L 2 (Ω), Gaussian Ku f G, texture Ku f L 1 (Ω), outlier F = Ku f log Ku, poisson Ω Ω Ku + f Ku, multiplicative (Ku f ) 2, sample Ω u 2 (Ku f ) 2 Ku, ultrasound Ω (WHU) June 5, / 118
17 Variational Image Restoration Modeling Regularization Term (prior of u) u L2 (Ω), Tikhonov regularizer, 1960 s u H 1 (Ω), Tikhonov regularizer, 1960 s u, Γ M S, Mumford-Shar regularizer, 1980 s u TV (Ω), TV regularizer, 1992, Osher Wu L1 (Ω), Wavelet regularizer, 1990 s R(u) = u E, Euler s elastica regularizer, 1980 s, M-S u TV 2 (Ω), TV 2 regularizer, 2000 s, Scherzer u HOR : M, Reduced TV 2 regularizer, 2004, T.Chan u ICTV (Ω), Inf-conv regularizer, 1997, Lions, Chambolle u TGV (Ω),... Tgv regularizer, 2010, Kunisch (WHU) June 5, / 118
18 Variational Image Restoration Modeling u L 2 (Ω) convex differentiable but no geometrical information and poor noise killing u H 1 (Ω) convex differentiable but do not keep jumps u(x, y), (x, y) Ω, Ω = (a, b) (c, d), for a.e y (c, d), u(, y) H 1 (a, b) H ölder(1/2). Mumford-Shar λ ] [(1 v i+0.5,j )(u i+1,j u i,j ) 2 +(1 v i,j +0.5 )(u i,j +1 u i,j ) 2 +µ i,j i,j R M S (u, Γ) = λ u 2 + µ Γ h Ω\Γ ensure spatial regularity and keep edges but non-convex (v i+0.5,j + v i,j +0.5 ) (WHU) June 5, / 118
19 Variational Image Restoration Modeling u TV { } Du := sup u gdx : p C0 (Ω, R2 ), p 1. Ω Ω Denote the Rodon measure Ω Du by u TV. Important property: Du = u + u + d h 1 and Du = dsdl Γ Γ Ω {u=l} edge preserving convex but non differentiable and cause stair case Euler s elastica (α + β κ 2 )ds Γ + u E = (α + β κ 2 )dsdl = (α + β( u {u=l} Ω u )2 ) Du preserve both jumps and smoothness but nonconvex (WHU) June 5, / 118
20 Variational Image Restoration Modeling u TV 2 u TV 2 { } := sup u 2 vdx : v C0 (Ω, S 2 2 ), v F 1 Ω convex, take care of flatten domain but blur the the boundary. u M u TV 2 { } := sup u vdx : v C0 (Ω), v 1 Ω convex, weaker smoothness but also do not keep jump since u L 1 (Ω) and u M (Ω) u W 1,1 (Ω) (WHU) June 5, / 118
21 Variational Image Restoration Modeling u ICTV (Ω) { } u ICTV (Ω) := inf α u v v TV (Ω) + β v TV 2 (Ω) { = inf α v sup p 1 p C 0 (Ω,R2 ) Ω (u v) pdx + β sup q 1 q C 0 (Ω,S 2 2 ) = sup inf. and inf is attained when α p = p,q v β 2 q Ω } v 2 qdx convex and utilizing structure of the image preserve both smoothness and constant jump (WHU) June 5, / 118
22 Variational Image Restoration Modeling u GTV (Ω) u GTV (Ω) := sup u 2 qdx (let p = q in u ICTV ) q α Ω q β q C 0 (Ω,S 2 2 ) Wu L 1 (Ω) W can be FT, let, dictionary... natural images can be sparsely approximate under let bases large let coefficients appear at the singularities different let has different vanishing moment let transform can be seen as an multi-differential operator which can detect the underling regularity of the image adaptively (WHU) June 5, / 118
23 Variational Image Restoration Modeling HOR MODEL TO REDUCE STAIR CASE A. Chambolle and P. Lions min u 1+u 2 λ 1 u 1 TV + λ 2 H (u 2 ) F L 1 + K (u 1 + u 2 ) f 2 L 2 T. Chan, S. Esedoglu, and F. Park min λ 1 u 1 u TV + λ 2 u 2 p 1+u 2 L 1 + K (u 1 + u 2 ) f 2 L, p = 1, 2 2 T. Chan, A. Marquina, and P. Mulet min u λ 1 u TV + λ 2 Φ( u ) (Lu) 2 L 1 + Ku f 2 L 2 (WHU) June 5, / 118
24 Variational Image Restoration Modeling K. Kunisch,K. Bredies, and T. Pock min u,v λ 1 ε(v) + λ 2 u v L 1 + Ku f 2 L 2 Osher, S, Tai, X.C.,Rahman, T min τ TV + 1 τ f 2, s.t. τ = 0 τ 2λ L 2 min u u TV u, τ τ, s.t. Ku f L 2 σ(n) L 2 (WHU) June 5, / 118
25 Variational Image Restoration Modeling Tight Frames Let X L 2 (R) to be countable, X is a tight if f 2 2 = < f, h > 2, f L 2 (R). h X It is equivalent to f = h X < f, h > h, f L 2 (R). Representation of f in terms of h is not unique. The sequence {< f, h >} is called the canonical frame coefficients. (WHU) June 5, / 118
26 Variational Image Restoration Modeling Wavelet Frames A wavelet system is the collection of the dilations and the shifts of a finite set Ψ L 2 (R) X (Ψ) = {2 k/2 ψ(2 k x j ) : ψ Ψ, k, j Z} Theorem X (Ψ) is a tight frame iff its "dual Gramian" is the identity, i.e., ^ψ(2 k ω) 2 = 1, ψ Ψ k Z a.e and ^ψ(2 k ω) ^ψ(2 k (ω + (2j + 1)2π)) = 0, a.e j Z. ψ Ψ k=0 (WHU) June 5, / 118
27 Variational Image Restoration Modeling Wavelet Frame from Multiresolution Analysis Start with a function refinable ψ L 2 (R) with mask h 0, i.e. φ(x ) = 2 k Z h 0 (k)φ(2x k). Let Ψ = {ψ 1, ψ 2,, ψ r }, where ψ i (x ) = 2 k Z h i (k)φ(2x k), with wavelet masks h i. (WHU) June 5, / 118
28 Variational Image Restoration Modeling Matrix Representation Let rows of W be a frame, i.e. W T W = I. Decomposition: c = Wf. Reconstruction: f = W T c. W can be generated by tight frame filters obtained via UEP. Framelet Based Balanced Model { 1 min K W T c f p c p + α (I WW T )c } 2 + β c L p (Ω) 2 l 2 l 1, p = {1, 2} (WHU) June 5, / 118
29 Algorithms for min u J (u) = F (Ku, f ) + λr(u) First Optimization then Discretization first derive Euler-Lagrange equation { F (Ku, f ) + λ R(u) = 0 B.D. then time marching: u = F (Ku, f ) λ R(u) t u(0, ) = f B.C. it does work but high nonlinearity + nonsmoothness = bad CFL condition (slow) (WHU) June 5, / 118
30 Algorithms for min u J (u) = F (Ku, f ) + λr(u) First Discretization and Optimization (based on operator splitting,alternative direction,nesterov s acceleration ) State-of-the-Art-Methods Augmented-Lagrangian-Type Methods Forward-Backward Splitting Nesterov s acceleration A Unified Primal-Dual Algorithm (WHU) June 5, / 118
31 Algorithms for min u J (u) = F (Ku, f ) + λr(u) Augmented-Lagrangian-Type Methods minimize subject to H (u) + G(v) Au + Bv = b Algorithm 1 ADMM(GADM) Require: v 0 R Nv, λ 0 R N b, τ > 0 1: for k = 0, 1, do 2: u k+1 = arg min u H (u)+ < λ k, Au > + τ 2 b Au Bv k u u k 2 Q 3: v k+1 = arg min u G(u)+ < λ k, Bv > + τ 2 b Au k+1 Bv v v k 2 P 4: λ k+1 = λ k + τ(b Au k+1 Bv k+1 ) 5: end for (WHU) June 5, / 118
32 Algorithms for min u J (u) = F (Ku, f ) + λr(u) minimize subject to H (u) + G(v) Au + Bv = b Algorithm 2 AMA Require: λ 0 R N b, τ > 0 1: for k = 0, 1, do 2: u k+1 = arg min u H (u)+ < λ k, Au > 3: v k+1 = arg min u G(u)+ < λ k, Bv > + τ 2 b Au k+1 Bv 2 4: λ k+1 = λ k + τ(b Au k+1 Bv k+1 ) 5: end for (WHU) June 5, / 118
33 Algorithms for min u J (u) = F (Ku, f ) + λr(u) Forward-Backward Splitting minimize J (x ) Algorithm 3 Gradient Descent 1: for k = 0, 1, do 2: x k+1 = x k + τ J (x k ) 3: end for F = H + G Algorithm 4 FBS 1: for k = 0, 1, do 2: x k+1 = J τ G (x k τ H (x k )) 3: end for (WHU) June 5, / 118
34 Algorithms for min u J (u) = F (Ku, f ) + λr(u) Nesterov s acceleration minimize J (x ) Algorithm 5 Nesterov s Optimal Gradient Descent Require: α 0 = 1, x 0 = y 1 R N, τ < 1/L( F ) 1: for k = 1, 2, 3, do 2: x k = y k τ J (y k ) 3: α k+1 = (1 + 4α 2 k + 1)/2 4: y k+1 = x k + (α k 1)(x k x k 1 )/α k+1 5: end for (WHU) June 5, / 118
35 Algorithms for min u J (u) = F (Ku, f ) + λr(u) J = H + G Algorithm 6 FISTA Require: y 1 = x 0 R N, α 1 = 1, τ < 1/L( G) 1: for k = 1, 2, 3, do 2: x k = J τ G (y k τ H (y k )) 3: α k+1 = (1 + 4α 2 k + 1)/2 4: y k+1 = x k + α k 1 α k+1 (x k x k 1 ) 5: end for (WHU) June 5, / 118
36 Algorithms for min u J (u) = F (Ku, f ) + λr(u) minimize subject to H (u) + G(v) Au + Bv = b Algorithm 7 Fast AMA Require: α 0 = 1, λ 1 = ^λ 0 R N b, τ < ρ(a T A) 1: for k = 0, 1, 2, do 2: u k = arg min H (u)+ < ^λ k, Au > 3: v k = arg min G(v)+ < ^λ k, Bv > + τ 2 b Au k Bv 2 4: λ k = ^λ k + τ(b Au k Bv k ) 5: α k+1 = ( α 2 k )/2 6: ^λ k+1 = λ k + α k 1 α k+1 (λ k λ k 1 ) 7: end for (WHU) June 5, / 118
37 Algorithms for min u J (u) = F (Ku, f ) + λr(u) minimize H (u) + G(v) subject to Au + Bv = b Algorithm 8 Fast ADMM Require: v 1 = ^v 0 R Nv, λ 1 = ^λ 0 R N b, τ > 0 1: for k = 1, 2, 3, do 2: u k = arg min H (u)+ < ^λ k, Au > + τ 2 b Au B ^v k 2 3: v k = arg min G(v)+ < ^λ k, Bv > + τ 2 b Au k Bv 2 4: λ k = ^λ k + τ(b Au k Bv k ) 5: if E k > 0 then 6: α k+1 = ( α 2 k )/2 7: ^v k+1 = v k + α k 1 α k+1 (v k v k 1 ) 8: ^λ k+1 = λ k + α k 1 α k+1 (λ k λ k 1 ) 9: else 10: α k+1 = 1, ^v k+1 = v k, ^λ k+1 = λ k 11: end if 12: end for (WHU) June 5, / 118
38 Algorithms for min u J (u) = F (Ku, f ) + λr(u) A Unified Primal-Dual Algorithm min F (Kx ) + G(x ), max x X ( ) G ( K y) + F (y) y Y min max < Kx, y > +G(x ) F (y) x X y Y Initialization: Choose τ, σ > 0, θ [0, 1], (x 0, y 0 ) X Y and set x 0 = x 0. Iterations (n 0): Update x n, y n, x n as follows: y n+1 = (I + σ F ) 1 (y n + σk x n ) x n+1 = (I + τ G) 1 (x n τk y n+1 ) x n+1 = x n+1 + θ(x n+1 x n ) (WHU) June 5, / 118
39 Algorithms for min u J (u) = F (Ku, f ) + λr(u) min x Ω Du + λ 2 u g 2 2 min max < u, div p > X + λ u X p Y 2 u g 2 2 δp(p) F (p) = δp(p) G(u) = λ 2 u g 2 2 p = (I + σ F ) 1 ( p) p i,j = p i,j max(1, p i,j ) (WHU) June 5, / 118
40 Algorithms for min u J (u) = F (Ku, f ) + λr(u) min u Ω Du + λ u g 1 min max < u, div p > X +λ u g u X p Y 1 δp(p) ũ i,j τλ u = (I + τ G) 1 (ũ) ũ i,j + τλ g i,j if ũ i,j g i,j > τλ if ũ i,j g i,j < τλ if ũ i,j g i,j τλ (WHU) June 5, / 118
41 Algorithms for min u J (u) = F (Ku, f ) + λr(u) min u Ω Du + λ 2 Au g 2 2 min max < u, div p > X + λ u X p Y 2 Au g 2 2 δp(p) u = (I + τ G) 1 (ũ) u = arg min u u ũ 2τ F 1( τλf(g)f(k A ) + F(ũ) τλf(k A ) λ 2 k A u g 2 2 ) (WHU) June 5, / 118
42 Algorithms for min u J (u) = F (Ku, f ) + λr(u) min u X Φu 1 + λ 2 Au g 2 2 min u X Φu 1 + λ 2 u = (I + τ G) 1 (ũ) u i,j = ũ i,j ũ i,j +τλg i,j 1+τλ i,j D\I if (i, j ) I else (u i,j g i,j ) 2 (WHU) June 5, / 118
43 2 Proposed Model and Algorithm
44 Proposed Model and Algorithm Proposed Model { } 1 min u p Ku f p L p (Ω) + α u TV + β ωwu l, p = {1, 2}, = {a, i} 1 there exist at least one minimizer. convex, utilizes edge preserving property of total variation and the adaptivity of the framlet transform to the underlying regularity of image. Therefore, preserve both jumps and smoothness. (WHU) June 5, / 118
45 Proposed Model and Algorithm Algorithm:(ADMM for Fixed α and β) 1 min u 2 Ku f 2 L 2 (Ω) + α u TV + β ωwu l (P) 1 min max u,v,z p,q L(u, v, z ; p, q) (PD) L(u, v, z ; p, q) = 1 2 Ku f 2 + u v, p + r 2 u v α v 1 + Wu z, q + s 2 Wu z β ωz 1 (WHU) June 5, / 118
46 Algorithm for Proposed Model algorithm ( ) u 0 = f, v 0 = 0, z 0 = 0; p 0 = 0, q 0 = 0, given α 0, β 0 γ > 0 for l = 1, 2, 3,, for k = 1, 2, 3,, (u k, v k, z k ) = arg min u,v,z L α l 1,β l 1(u, v, z ; pk 1, q k 1 ) p k = p k 1 r(p k 1 u k ) q k = q k 1 s(q k 1 Wz k ) stop or k k + 1 end for α l = 1 γ+1 ( 1 2 β l = 1 γ+1 ( 1 2 stop or l l + 1 end for Ku k f βl 1 ωwu k l 1)/ u k 1 Ku k f αl 1 u k 1 )/ ωwu k l 1 (WHU) June 5, / 118
47 Algorithm Detail Alternative Direction Minimization for (u k, v k, z k ) = arg min u,v,z L α l 1,β l 1(u, v, z ; pk 1, q k 1 ) fix v = v k 1,z = z k 1, solving u k u k = arg min L α l 1,β l 1(u, v k 1, z k 1 ; p k 1, q k 1 ) u the optimal conditon is a linear systerm. fix u = u k, solving v k, z k v k = arg min L α l 1,β l 1(u k, v, z k 1 ; p k 1, q k 1 ) v z k = arg min z L α l 1,β l 1(u k, v k, z ; p k 1, q k 1 ) two close form solution defined by threshold functions. (WHU) June 5, / 118
48 Complexity and Convergence Computational Complexity: O(m n) or O(m n) log(m n) Convergence Analysis: Convergence for u k with fix α l, β l : X = R m n, Y = X X, Z = W (X ), A = [, W ] : X X Y Z F (u) = 1 2 Ku f 2 2 : X R, G(v) = α v 1 1 +β ωv 2 1 : Y Z : R then, min u,v F (u) + G(v), s.t. Au = v by ADMM is inner loop of algorithm ( ) Convergence for α l, β l : {α l }, {β l } are monotone in the same way depend on α 0, β 0. (WHU) June 5, / 118
49 3 Numerical Results
50 Denoising oringal image (WHU) June 5, / 118
51 Denoising observed image,psnr 23.70dB (WHU) June 5, / 118
52 Denoising tv restoration,psnr 34.29dB, CPU 0.84s (WHU) June 5, / 118
53 Denoising balanced restoration,psnr 31.53dB, CPU 2.17s (WHU) June 5, / 118
54 Denoising chan 4th ordr restoration,psnr 35.25dB, CPU 8.33s (WHU) June 5, / 118
55 Denoising tgv restoration,psnr 35.72dB, CPU 27.69s (WHU) June 5, / 118
56 Denoising tv frame restoration,psnr 33.95dB, CPU 5.44s (WHU) June 5, / 118
57 Denoising oringal image (WHU) June 5, / 118
58 Denoising observed image,psnr 23.47dB (WHU) June 5, / 118
59 Denoising tv restoration,psnr 28.35dB, CPU 0.39s (WHU) June 5, / 118
60 Denoising balanced restoration,psnr 27.10dB, CPU 4.47s (WHU) June 5, / 118
61 Denoising chan 4th ordr restoration,psnr 28.01dB, CPU 8.19s (WHU) June 5, / 118
62 Denoising tgv restoration,psnr 28.07dB, CPU 26.92s (WHU) June 5, / 118
63 Denoising tv frame restoration,psnr 28.23dB, CPU 5.97s (WHU) June 5, / 118
64 Denoising oringal image (WHU) June 5, / 118
65 Denoising observed image,psnr 22.82dB (WHU) June 5, / 118
66 Denoising tv restoration,psnr 26.19dB, CPU 0.83s (WHU) June 5, / 118
67 Denoising balanced restoration,psnr 25.72dB, CPU 2.78s (WHU) June 5, / 118
68 Denoising chan 4th ordr restoration,psnr 25.98dB, CPU 8.94s (WHU) June 5, / 118
69 Denoising tgv restoration,psnr 25.58dB, CPU 23.84s (WHU) June 5, / 118
70 Denoising tv frame restoration,psnr 26.21dB, CPU 6.45s (WHU) June 5, / 118
71 Denoising oringal image (WHU) June 5, / 118
72 Denoising observed image,psnr 24.10dB (WHU) June 5, / 118
73 Denoising tv restoration,psnr 32.14dB, CPU 0.52s (WHU) June 5, / 118
74 Denoising balanced restoration,psnr 30.38dB, CPU 5.44s (WHU) June 5, / 118
75 Denoising chan 4th ordr restoration,psnr 31.46dB, CPU 12.97s (WHU) June 5, / 118
76 Denoising tgv restoration,psnr 32.19dB, CPU 16.27s (WHU) June 5, / 118
77 Denoising tv frame restoration,psnr 31.86dB, CPU 9.28s (WHU) June 5, / 118
78 Deblurring oringal image (WHU) June 5, / 118
79 Deblurring observed image,psnr 16.60dB (WHU) June 5, / 118
80 Deblurring tv restoration,psnr 33.12dB, CPU 2.78s (WHU) June 5, / 118
81 Deblurring balanced restoration,psnr 30.57dB, CPU 24.53s (WHU) June 5, / 118
82 Deblurring tv frame restoration,psnr 30.93dB, CPU 13.80s (WHU) June 5, / 118
83 Deblurring oringal image (WHU) June 5, / 118
84 Deblurring observed image,psnr 18.13dB (WHU) June 5, / 118
85 Deblurring tv restoration,psnr 29.44dB, CPU 2.88s (WHU) June 5, / 118
86 Deblurring balaced restoration,psnr 28.84dB, CPU 18.69s (WHU) June 5, / 118
87 Deblurring tv frame restoration,psnr 29.08dB, CPU 7.86s (WHU) June 5, / 118
88 Deblurring oringal image (WHU) June 5, / 118
89 Deblurring observed image,psnr 18.55dB (WHU) June 5, / 118
90 Deblurring tv restoration,psnr 24.72dB, CPU 2.84s (WHU) June 5, / 118
91 Deblurring balanced restoration,psnr 24.33dB, CPU 27.03s (WHU) June 5, / 118
92 Deblurring tv frame restoration,psnr 23.92dB, CPU 11.19s (WHU) June 5, / 118
93 Deblurring oringal image (WHU) June 5, / 118
94 Deblurring observed image,psnr 18.32dB (WHU) June 5, / 118
95 Deblurring tv restoration,psnr 27.39dB, CPU 1.70s (WHU) June 5, / 118
96 Deblurring blanced restoration,psnr 27.53dB, CPU 24.80s (WHU) June 5, / 118
97 Deblurring tv frame restoration,psnr 27.55dB, CPU 11.50s (WHU) June 5, / 118
98 Inpainting oringal image (WHU) June 5, / 118
99 Inpainting observed image,psnr 21.68dB (WHU) June 5, / 118
100 Inpainting tv restoration,psnr 43.01dB, CPU 95.63s (WHU) June 5, / 118
101 Inpainting balanced restoration,psnr 31.60dB, CPU 34.14s (WHU) June 5, / 118
102 Inpainting tvframe restoration,psnr 42.20dB, CPU s (WHU) June 5, / 118
103 Inpainting oringal image (WHU) June 5, / 118
104 Inpainting observed image,psnr 14.27dB (WHU) June 5, / 118
105 Inpainting tv restoration,psnr 27.82dB, CPU 13.03s (WHU) June 5, / 118
106 Inpainting balanced restoration,psnr 27.35dB, CPU 32.02s (WHU) June 5, / 118
107 Inpainting tgframe restoration,psnr 27.65dB, CPU s (WHU) June 5, / 118
108 Inpainting oringal image (WHU) June 5, / 118
109 Inpainting observed image,psnr 18.86dB (WHU) June 5, / 118
110 Inpainting tv restoration,psnr 34.27dB, CPU 11.02s (WHU) June 5, / 118
111 Inpainting balanced restoration,psnr 31.20dB, CPU 9.03s (WHU) June 5, / 118
112 Inpainting tvframe restoration,psnr 32.32dB, CPU 47.75s (WHU) June 5, / 118
113 Inpainting oringal image (WHU) June 5, / 118
114 Inpainting observed image,psnr 23.05dB (WHU) June 5, / 118
115 Inpainting tv restoration,psnr 27.24dB, CPU 55.55s (WHU) June 5, / 118
116 Inpainting balanced restoration,psnr 26.82dB, CPU 29.52s (WHU) June 5, / 118
117 Inpainting tvframe restoration,psnr 26.85dB, CPU s (WHU) June 5, / 118
118 Thank you!
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