Enhancing the Quality of Medical Images Containing Blur Combined with Noise Pair

Автор: Nguyen Thanh Binh, Vo Thi Hong Tuyet

Журнал: International Journal of Image, Graphics and Signal Processing(IJIGSP) @ijigsp

Статья в выпуске: 11 vol.7, 2015 года.

Бесплатный доступ

In many fields, images become a useful tool containing data of which medical image is an example. The diagnosis depends on the skills of the doctors and image clarity. In the real world, most of medical images consist of noise and blur. This problem reduces the quality of images and causes difficulties for doctors. Most of the tasks of increasing the quality of medical images are deblurring or denoising process. This is the difficult problem in medical image processing, because it must keep the edge features and avoid the loss of information. In case of a medical image which contains noise combined with blur, it is more difficult. In this paper, we have proposed a method for increasing the quality of medical images in case that blur combined with noise pair is available in medical images. The proposed method is divided into two steps: denoising and deblurring. We use curvelet transform combined with bayesian thresholding for the denoising step and use the augmented lagrangian method for the deblurring step. For demonstrating the superiority of the proposed method, we have compared the results with the other recent methods available in literature.

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Deblurring, denoising, curvelet transform, bayesian thresholding, augmented lagrangian method

Короткий адрес: https://sciup.org/15013923

IDR: 15013923

Текст научной статьи Enhancing the Quality of Medical Images Containing Blur Combined with Noise Pair

Published Online October 2015 in MECS

In medical imaging diagnosis, doctors must rely on the captured images such as computed tomography (CT), magnetic resonance imaging (MRI), etc. to diagnose abnormal defects or diseases that cause damage to the patient's body, such as bone fractures, brain tumors, etc. The diagnosis depends on the skills of the doctors and image clarity. The quality of medical images depends on the environment, capture device, person’s shooting skills, etc. In the real world, most of medical images contain of noise and blur. This problem reduces the quality of images and causes difficulties for viewers (doctors). Medical image noising, blur, noise or pair can have influence on the diagnostic process. A small detail in a medical image is very useful for treatment process. Therefore, denoising and deblurring become popular in image processing. The goal of denoising and debluring is to remove noise and blur details from the corrupted image while maintaining edge features.

In the past, many methods have been proposed for denoising and deblurring such as wavelet transform [1, 2, 3], contourlet transform [5], nonsubsampled contourlet transform [6,  7], ridgelet transform [8], curvelet transform [9, 10, 11], etc. Most of these methods use thresholdings for the process of improvement. Many thresholdings are proposed such as [4, 23, 24]: stationary, cycle-spinning, steerable wavelet transforms, etc. The results were significantly improved when the above methods were used. However, the cases of image denoising or deblurring are very hard work and still a great challenge. Especially, with the pair case, which has blur combined with noise, it is more difficult.

The curvelet transform [11], a new X-let transform multiscale transform, is like the wavelet transform but it has the directional parameters, which contains elements with a very high degree of directional specificity. The results of curvelet transform for denoising are good in some other cases. However, it still needs to continue to be improved. Augmented lagrangian method [13] has given the good results, especially for deblurring or denoising, but the results are not good in case of blur and noise pair. In paper [12], the authors proposed a new method for denoising images, which is based on multilevel threshold in curvelet domain combined with cycle spinning for good results. Mingwei [16] proposed the applying bayesian thresholding in nonsubsampled contourlet transform. With these ideas, we think that the combined methods and thresholdings can give the good result to each process. The initial results are given our previous algorithms in [25, 26] which presented the combination between transform and thresholding. In this paper, we have proposed a method for increasing the quality of medical images in case that blur combined with noise pair is available in medical images. The proposed method is divided into two steps: denoising and deblurring. We use curvelet transform combined with bayesian thresholding for the denoising step and use augmented lagrangian method for the deblurring step. For demonstrating the superiority of the proposed method, we have compared the results with the other recent methods available in literature such as: discrete wavelet transform (DWT) [2], curvelet transform [11] and augmented lagrangian [13]. For performance measure, we have used Peak Signal to Noise Ratio (PSNR) and Mean Square Error (MSE) and it has shown that the results of the present method are better than the other methods. The rest of the paper is organized as follows: in section II, we describe the basic of curvelet transform, principle bayesian thresholding and augmented lagrangian method, which we used; details of the proposed method are given in section III; the results of the proposed method are presented in section IV and our conclusions are made in section V.

  • II.    Background
  • A.    Curvelet Transforms

Ridgelet transforms [8] in two dimensions provide a sparse representation of smooth functions and perfectly straight edges. Rigelet transforms occur at all scales, locations and orientations; and each has global length and variable widths. And ridgelets have two approaches: monoscale and multiscale ridgelets. Ridgelets combined with a spatial bandpass filtering operation to isolate different scales were curvelets.

Curvelets [11] are better than wavelet based transforms in case of representing edges and other singularities along curves. Curvelets can be translated and dilated, similar to wavelet transforms. On the first decomposing an image into subbands, the curve of curvelets is displayed with width ~ length2. After decomposing, each scale is analyzed by a local ridgelet transform. Similar to ridgelets at occuration; but, while ridgelets have global length and variable widths, curvelets in addition to a variable width have a variable length and so a variable anisotropy.

The basic process of the digital realization for curvelet transforms can be summarized [11, 12]:

Fig. 1. The process of curvelet transforms.

f irstly , Subband decomposition. The image f is decomposed into subbands:

f h^( P o f , A i f , A 2 f ,...)           (1)

Secondly , Smooth partitioning. Each subband is smoothly windowed into “squares” of an appropriate scale (of sidelength ~2-s):

A s f l->( WQ A s f ) q^          (2)

where w is a collection of smooth window localized around dyadic squares:

Q = [ k / 2 s ,( k + 1) / 2 s ] x [ k 2 / 2 s ,( k 2 + 1) / 2 s ]

Thirdly , Renormalization. Each resulting square is renormalized to unit scale:

g Q = ( T q ) - 1( W q a s f ), Q e Q s        (4)

Finally , Ridgelet analysis. Each square is analyzed via the discrete ridgelet transform.

In this definition, the two dyadic subbands [22s, 22s+1] and [22s+1, 22s+2] are merged before applying the ridgelet transform.

  • B.    Bayesian Thresholdings

Most of the existing thresholding procedures are essentially minimax. They do not take into account some specific properties of a concrete object in which we are interested. Now, we specify a prior distribution on the wavelet coefficients within a bayesian framework.

The estimate noise variance σ and signal variance δ can be obtained by equation [14]:

σ=

^ median (| w i,j| ) ) 0.6745

and

δ2 =max

MN

1         w2 -σ2,0

MxN t=1 j=1 t,j

where w i, j is the lowest frequency coefficient after the transformation, MxN is the sub-band’s size.

Abramovich [14] proposed a Bayesian formalism which gives rise to a type of wavelet threshold estimation in nonparametric regression. They establish a relationship between the hyperparameters of the prior model and the parameters of those Besov spaces within which realizations from the prior will fall. The bayesian threshold solves the standard nonparametric regression problem [14]:

y. = g(t i ) +e , ., i = 1,..., n           (7)

where h=i/n and G. are independent identically distributed normal variables with zero mean and variance 5 2, and they will recover the unknown function g from the noised data without assuming any particular parametric form.

Bayesian thresholdings based on discrete wavelet transforms. The discrete wavelet coefficients are defined by the vector of function values. Based on this vector, which rules, apply them to hard and soft thresholding. In the hard thresholding, the important coefficients remain unchanged while the important coefficients are reduced by the absolute threshold value in the soft thresholding.

  • C.    Augmented Lagrangian Method

A linear shift invariant imaging system is modeled as [13]:

g = Hf + η                  (8)

where f e R MN X1 is a vector denoting the unknown (potentially sharp) image of size M x N, g e R MN X1 is a vector denoting the observed image, n e R MN X1 is a vector denoting the noise, and the matrix H e R MN X MN is a linear transformation representing convolution operation. And the goal of image restoration is from the observed image g , algorithms will recover f .

The algorithm is proposed to minimize a total variation optimization problem for spatial-temporal data by Stanley [13]. This algorithm uses an augmented lagrangian method to solve the constrained problem. Two problems are considered as TV/L1 and TV/L2 minimization are defined as:

minimize   ^|\Hf - g ||2 +|| f||7.r            (9)

and minimize д|Hf - g||1 +| f/;         (10)

With equations, μ is the regularization parameter. The idea of the augmented lagrangian method is to find a saddle point. And we can use the alternating direction method (ADM).

The idea of augmented lagrangian is to find a saddle point of L(f, u, y); then, they use the alternating direction method (ADM) to solve f-subproblem, u-subproblem with TV/L2 and f-subproblem, u-subproblem and r-subproblem with TV/L1. The equation as [13]:

minimize μ Hf-g 2 + u           (11)

and minimize ^||r || 1+||u||1            (12)

Subject to r = Hf - g and u = Df. Algorithm of TV/L1 or TV/L2 can be summarized as follows [13]:

  • (i)    Input: vector denoting the observed image and convolution matrix, regularization parameter, the isotropic total variation.

  • (ii)    Set parameter with value default for each types of TV/L1 or TV/L2.

  • (iii)    Initialize for the first value, such as: f, u.

  • (iv)    Compute the matrices of the first-order forward finite difference operators along the horizontal, vertical and temporal directions.

  • (v)    With not coverage do:

+ Solve the sub problems and update parameter.

+ Check convergence, if false continue.

  • III.    The Proposed Method for Image Denoising Combined with Deblurring

Blur images are very difficult for image processing, especially with images which consist of blur and noise pair. In this section, we propose a new approach for image deblurring, with blur and noise pair based on curvelet transforms combined with bayesian thresholding and augmented lagrangian method.

Curvelets and ridgelets take the form of basic elements, which exhibit very high directional sensitivity and are highly anisotropic. Curvelet transforms, based on the principle of anisotropic scaling, have given entirely different scale an isotropy of wavelet transforms.

As mentioned in section 1, Starck [11] used the curvelet transform for image denoising. Do [6] developed the contourlet transform using a double filter bank structure for denoising. Donoho [5] proposed the ridgelet transform and using it for denoising. The ridgelet transform is not sufficient to handle linear discontinuities in images. Donoho [8] proposed the curvelet transform by utilizing the properties of the ridgelet transform. To compensate for the lack of translation invariance property of the curvelet transform, we apply the principle of bayesian thresholding for image denoising. Because the thresholding may overcome this disadvantage. Bayesian thresholding for deblurring images [15, 22] is based on the median of thresholding and the denoising [15] for noise images are not at all. We proposed the combination in [25] which use ridgelet transform and bayesian thresholding for denoising step, then we apply the Wiener filter for deblurring step in denoising images. With deblurring, augmented lagrangian method [13] is the very excellence method for deblurring process. In [26], we use the curvelet transform for denoising step and augmented lagrangian for deblurring step. But with [26], in many types of noise or blur, we not chance algorithm for each types. Therefore, we divide medical image processing with the blur and noise pair into two processes: denoising and deblurring, and chance the algorithm to depend on each types blur or noise. The proposed method includes two steps. The proposed method is used as figure 2:

Fig. 2. The processing of proposed method.

Firstly, the inputs are the blur combined with noise in images. We use curvelet transforms for denoising images, the process of curvelets is as follows [11]:

(i) apply the b 1 =b min

à trous algorithm with scales and set

  • ( ii) for. j=1, .„, j do

  • +    partition the subband w j with a block size b j and apply the digital ridgelet transform to each block;

  • +    if j modulo 2 = 1 then b j+1 =2b j  else b j+1 =b j

The sidelength of the localizing windows is doubled at every other dyadic subband.

Bayesian thresholding is the composition in wavelet transforms, calculates median thresholding and shows result based on the new thresholding. The process of bayesian thresholding can be achieved as follows:

After this period, the input images become denoising images. The result of denoising with curvelet transforms combined with bayesian is good in the types of noise, such as: gaussian, speckle, etc.

Figure 3 shows the denoising image in case of speckle noise using curvelet transforms combined with bayesian thresholdings.

(d)                         (e)

Fig. 3. A noise image with speckle noise and denoising images by different methods.

  • (a)    Original image.

  • (b)    Noise image (PSNR = 20.0232 db).

  • (c)    Denoising image by DWT (PSNR = 22.7776 db).

  • (d)    Denoising image by curvelet transforms (PSNR = 28.8155 db).

  • (e)    Denoising image by curvelet transforms combined with bayesian thresholdings (PSNR = 29.0008 db).

From figure 3, the result of the method, curvelet transforms combined with bayesian thresholdings, is the highest. But with Gaussian noise, we use db2 for decomposition and db4 in speckle noise. The results are very satisfactory because Gaussian noise is the summation and speckle noise is the multiplication.

The summation is the noise value will add in each pixel of medical images. So, decomposition needn’t high level. The multiplication is the noise value will accumulate in each pixel of medical images. Removed the multiplication noise must double decomposition value.

Secondly , it is medical image deblurring. The noise in the blur combined with noise images has been removed in the curvelet domain in the above period. The blur in images is not removed more. To remove the blur, we use augmented lagrangian for the output images from the previous period.

In here, we use augmented lagrangian TV/L2 algorithm [13] to remove the blur. The problem that we solve in TV/L2 minimization is:

minimize ^|\Hf - g ||2 +|I f^          (13)

Algorithm of TV/L2, which is used in the proposed method, can be summarized as follows [13]:

  • (i)    Input: vector denoting the observed image (g) and convolution matrix (H), regularization parameter Ц , the isotropic total variation Д , в , Д

  • (ii)    Set parameter with value default for p = 1 ( p is a regularization parameter) for Gaussian blur and p = 2 for motion blur. Then set a = 0.7.

The reason of this choice: Gaussian blur is to strengthen the standard deviation, but motion blur is the movement of objects and sightseeing. Therefore, we set default for regularization parameter of Gaussian blur is 1 and motion blur is 2.

  • (iii)    Initialize f 0 = g, u 0 = Df 0 , y = 0, k = 0. (y is the Lagrange multiplier)

  • (iv)    Compute the matrices of the first-order forward finite difference operators along the horizontal, vertical and temporal directions.

With not coverage do:

  • 1.    Solve the f-subproblem is:

f t + 1 = arg min ^ | H - g ||2 - y t ( ut - D f ) + p u ut - D f ||2 f 2                             2

by equation:

F [ M HTg + p , Du - Dy ]

A| F [ H ] 2 + p , ( F [ D , ] 2 + F [ D y Л 2 + F [ D t ] 2 )

where F denotes the three-dimensional Fourier Transform operator.

2. Solve the u-subproblem is:

PSNR=20log (

MAX

MSE

)

u k + 1= argmini | u | L - y T ( u - Df k +i ) + ^-Wu - Df k +i||2 u 2

by equation:

ux = max ] Ivxl- — ,0f * sign (vx )

I      PrJ

3. Update the Lagrange multiplier:

Ук+1 = yk - Pr(uk+1 - Dfk+1)

where MAX 1 is the maximum pixel value of the image. The proposed method is compared with DWT, CT, and AL method based on the MSE and PSNR values. The smaller the value of MSE is, the better it is. The higher the value of PSNR is, the better it is. We test so many medical images. In here, we show some test cases.

Figure 4 shows the deblurring of blur and noise image which has Gaussian blur combined with Gaussian noise by our proposed method. Figure 5 shows the deblurring of blur and noise image which has Gaussian blur combined with Speckle noise by our proposed method.

4. Update:

(a)                 (b)                 (c)

P r

={

YP r , if || u k +1 - Df k +112 ^ 4 u k - Df k 112 p r , otherwise

5. Check convergence: if

(d)                   (e)                   (f)

Fig. 4. Denoising and deblurring images in case Gaussian blur is combined with Gaussian noise by different methods.

II f + 1 - f k lLI f lL s tol         (20)

then break, else continue.

IV. Experiments and Results

In this section, we apply the procedure described in section 3 and achieved superior performance in our deblurring experiments as demonstrated in this section. For performance evaluation, we compare the results of the proposed method based on curvelet transforms combined with bayesian thresholdings and augmented lagrangian (CTBTAL) with the methods: discrete wavelet transform (DWT), curvelet transforms (CT) and augmented lagrangian (AL). We test the result in medical image datasets, this dataset includes different images of different sizes: 256x256, 512x512. Hard thresholding is applied to the coefficients after decomposition in the curvelet domain. All of the above methods are done on our program and the same images at the similar scale.

The quality of images is improved by comparison with the value of Mean Square Error (MSE) and Peak Signal-to-Noise Ratio (PSNR). The MSE is defined as:

  • (a)    Original image.

  • (b)    Blur combined with noise in image (PSNR = 25.2391db).

  • (c)    Denoised and deblurred image by DWT (PSNR = 28.0690 db).

  • (d)    Denoised and deblurred image by AL (PSNR = 26.0581db).

  • (e)    Denoised and deblurred image by CT (PSNR = 27.8005db).

  • (f)    Denoised and deblurred image by CTBTAL (PSNR = 29.0626 db).

(d)                  (e)                   (f)

Fig. 5. Denoising and deblurring images in case Gaussian blur is combined with Speckle noise by different methods.

NN

MSE= 1       (x -y ) 2

NxN i=1 j=1 i,j i,j

where x is the image which has blur and noise, y is the image result and N x N is the size of image. PSNR is used as the measure of quality of reconstruction of image deblurring or denoising, defined as:

  • (a)    Original image.

  • (b)    Blur combined with noise image (PSNR = 28.9375 db).

  • (c)    Denoised and deblurred image by DWT (PSNR = 29.4235 db).

  • (d)    Denoised and deblurred image by AL (PSNR = 30.5175 db).

  • (e)    Denoised and deblurred image by CT (PSNR = 29.8517 db).

  • (f)    Denoised and deblurred image by CTBTAL (PSNR = 31.5662 db).

From figure 4 and figure 5, we see that the result of the proposed method (fig.(f)) is better than the other methods (fig.(c), fig.(d), fig.(e)). Figure 6 show the plot

of PSNR, MSE values of different image deblurring and denoising methods corrupted in case of Gaussian blur combined with Gaussian noise.

Fig. 6. Plot of PSNR and MSE values of denoised and deblurred images in case of Gaussian blur combined with Gaussian noise using different methods.

(b)

Fig. 7. Plot of PSNR and MSE values of denoised and deblurred images in case of Gaussian blur combined with speckle noise using different methods.

  • (a)    Plot of PSNRvalues of denoised and deblurred images.

  • (b)    Plot of MSE values of denoised and deblurred images.

Figure 8 shows the deblurring of blur and noise image in case of motion blur combined with Gaussian noise by our proposed method and the other method. Figure 9 also shows the deblurring of blur and noise image in case of motion blur combined with speckle noise by our proposed method and the other method.

(a)

c)

  • (a)    Plot of PSNRvalues of denoised and deblurred images.

  • (b)    Plot of MSE values of denoised and deblurred images.

    Figure 7 show the plot of PSNR, MSE values of different image denoising and deblurring methods corrupted in case Gaussian blur combined with speckle noise.

    (a)


(d)                   (e)                  (f)

Fig. 8. Denoising and deblurring images with motion blur combined with Gaussian noise by different methods.

  • (a)    Original image.

  • (b)    Blur combined with noise in image (PSNR = 16.9468 db).

  • (c)    Denoised and deblurred image by DWT (PSNR = 17.5966 db).

  • (d)    Denoised and deblurred image by AL (PSNR = 20.0532 db).

  • (e)    Denoised and deblurred image by CT (PSNR = 17.6140 db).

  • (f)    Denoised and deblurred image by CTBTAL (PSNR = 22.6687db).

    (d)                   (e)                  (f)

    Fig. 9. Denoising and deblurring images in case of motion blur combined with speckle noise different methods.


    • (a)    Original image.

    • (b)    Blur combined noise image (PSNR = 17.2759 db).

    • (c)    Denoised and deblurred image by DWT (PSNR = 17.4074 db).

    • (d)    Denoised and deblurred image by AL (PSNR = 20.1790 db).

    • (e)    Denoised and deblurred image by CT (PSNR = 17.6344 db).

    • (f)    Denoised and deblurred image by CTBTAL (PSNR = 20.9319 db).

From figure 8 and figure 9, we see that the result of the proposed method fig.(f) is better than the other methods (fig.(c), fig.(d) and fig.(e)). Figure 10 show the plot of PSNR, MSE values of different image denoising and deblurring methods corrupted in case of motion blur combined with Gaussian noise.

(a)

(b)

Fig. 10. Plot of PSNR and MSE values of denoised and deblurred images in case of motion blur combined with Gaussian noise using different methods.

  • (a)    Plot of PSNRvalues of denoised and deblurred images.

  • (b)    Plot of MSE values of denoised and deblurred images.

Figure 11 show the plot of PSNR and MSE values of different image denoising and deblurring methods corrupted in case of motion blur combined with speckle noise.

With figure 6, figure 7, figure 10 and figure 11, the PSNR values of the proposed method is the highest and the MSE values of the proposed method is the smallest. So, the proposed method performs better than discrete wavelet transform, curvelet transform and augmented lagrangian method. As mentioned in section 3, we improve the denoising processing. Therefore, the proposed method is better than the other method.

Fig. 11. Plot of PSNR and MSE values of denoised and deblurred images in case of motion blur combined with speckle noise using different methods.

  • (a)    Plot of PSNRvalues of denoised and deblurred images.

  • (b)    Plot of MSE values of denoised and deblurred images.

  • V. Conclusions

In this paper, we proposed the method for increasing the quality of blur combined with noise image by dividing it into two processes: denoising and deblurring. Firstly, we propose a new method for denoising image based on curvelet transform combined with bayesian thresholding. Then, we apply augmented lagrangian method for deblurring into denoising image. We test the proposed method with Gaussian blur combined with Gaussian noise pair, Gaussian blur combined with speckle noise pair, motion blur combined with Gaussian noise pair, and motion blur combined with speckle noise pair in medical images. From the results of the above section, we conclude that the proposed method works well and better than the other recent methods available in literature such as: discrete wavelet transforms, curvelet transforms and augmented lagrangian. Based on this idea, we think the combination methods can improve the quality of the image which has blurring and noising in case of denoising and deblurring step. Furthermore, we can develop this idea by combining thresholdings or filters in the deblurring or denoising step.

Appendix

Table 1. PSNR values (dB) of different denoised and deblured images with Gaussian blur combined with Gaussian noise.

Test Image

Image Size

Blur & Noise Image

DWT[2]

AL [13]

CT[11]

Proposed

Method

1

256 x 256

21.3958

25.3283

22.0264

25.1122

26.0232

2

20.6148

23.7412

21.0870

23.8914

24.7274

3

21.8062

25.0981

22.5222

25.2357

26.3515

4

19.3783

23.5501

19.6916

23.6754

24.9114

5

17.8001

24.9717

17.7717

24.9701

25.4818

6

16.0633

20.5249

16.3098

20.3469

21.1879

7

15.6079

22.3795

15.5836

22.2922

22.9893

8

14.9423

22.3773

14.8368

22.4524

23.1188

9

26.6524

31.6191

27.6351

31.3123

33.4234

10

24.1366

27.6435

25.0279

27.4658

29.4094

11

512 x

512

24.8521

32.9369

25.3458

32.5904

33.8393

12

21.7640

24.9861

22.7562

24.6530

26.2621

13

20.9965

23.5191

22.2377

23.1775

25.1051

14

24.2241

31.0421

24.8162

30.5948

32.3928

15

26.0221

31.8145

26.8493

31.3897

33.2971

16

20.0243

23.8463

20.8065

23.4914

25.4073

17

19.7131

23.8335

20.4062

23.4848

25.0111

18

21.2679

27.3645

21.8067

27.0792

29.2639

19

22.3948

28.6748

22.8228

28.3454

29.5994

20

23.9863

30.3258

24.5808

30.0443

31.6380

Table 2. PSNR values (dB) of different denoised and deblured images with Gaussian blur combined with speckle noise.

Test Image

Image Size

Blur & Noise Image

DWT[2]

AL[13]

CT [11]

Proposed Method

1

256 x 256

23.0920

25.5998

24.1175

25.3611

26.4193

2

20.2344

20.5992

20.5848

22.9130

23.2919

3

21.6390

21.7473

21.8942

21.7346

22.6895

4

17.5646

18.1684

17.5961

20.6789

20.9086

5

17.4910

21.0917

17.3516

24.2070

24.2351

6

18.1855

19.419

18.7048

20.5158

21.2482

7

22.4617

23.0035

23.6952

24.4640

25.9205

8

23.2818

23.9857

24.8751

25.1727

27.0829

9

23.8397

23.9484

23.9366

23.9670

24.1572

10

25.3260

25.7947

26.7436

27.2852

28.7624

11

512 x

512

25.9560

26.7559

26.1194

28.1989

28.2931

12

21.6175

23.8826

22.4633

24.5813

25.7629

13

21.0589

21.3584

22.2705

21.8535

22.8422

14

26.8943

27.4241

27.3779

28.2239

28.6356

15

22.6899

23.4968

22.8497

25.0090

25.4673

16

24.1621

24.2359

26.9951

24.2192

27.0083

17

20.7494

21.1499

21.5973

21.9186

22.4882

18

22.4913

23.2765

22.9129

24.0157

24.0499

19

24.6980

25.1384

25.2960

26.0356

26.0793

20

21.4004

21.7755

22.4325

22.3737

22.9852

Table 3. PSNR values (dB) of different denoised and deblured images with Motion blur combined with Gaussian noise.

Test Image

Image Size

Blur & Noise Image

DWT[2]

AL[13]

CT [11]

Proposed Method

1

256 x 256

23.0159

23.9126

24.1707

23.9211

25.4899

2

20.4164

21.5119

20.7121

21.6111

23.3620

3

18.7250

19.9783

19.4557

20.0889

22.9818

4

18.1161

20.0751

17.6501

20.1666

22.6791

5

19.6700

23.3954

17.5249

23.3652

24.3956

6

16.1661

17.6504

16.4068

17.6499

19.6690

7

16.3928

18.1925

15.8901

18.1829

20.7334

8

15.6207

18.6812

13.6431

18.6463

20.4013

9

17.6315

23.0562

14.6550

23.3315

23.8703

10

14.9204

20.6489

11.6314

20.8879

21.0647

11

512 x

512

15.0977

24.8670

11.4825

24.5610

24.8837

12

11.7964

19.4221

8.3987

19.3432

19.8086

13

11.3582

16.6619

8.4165

16.7060

17.1649

14

16.2420

22.8994

13.1730

23.1072

23.9144

15

14.6604

23.3671

11.0207

23.3920

23.6629

16

14.7424

17.6907

13.4450

17.6841

20.1851

17

13.4890

17.5244

11.2170

17.6103

19.0756

18

17.1167

21.5949

14.8758

21.6374

23.8379

19

17.1765

22.4123

14.5668

22.5664

23.7518

20

14.9819

22.5403

11.6565

23.0844

23.2075

Table 4. PSNR values (dB) of different denoised and deblured images with motion blur combined with speckle noise.

Test Image

Image Size

Blur & Noise Image

DWT[2]

AL[13]

CT [11]

Proposed Method

1

256 x

256

22.4100

24.7134

21.2940

24.6266

25.5927

2

19.1920

19.5068

17.5274

21.1395

21.3500

3

20.4008

20.3845

20.8618

20.4732

21.0328

4

17.7349

18.1884

15.5692

18.6866

20.0897

5

18.4259

21.3622

15.1831

22.6422

23.9545

6

18.5827

18.8027

20.9717

18.9451

21.5676

7

17.3083

18.0587

16.5054

19.5437

19.5775

8

16.8926

18.2756

14.1685

20.3064

21.0873

9

22.4852

22.8350

22.2780

23.9468

25.0694

10

19.7566

20.5159

17.2242

21.3251

22.9169

11

512 x

512

22.8737

23.4814

21.2150

23.2188

24.5355

12

18.1377

19.4882

18.1496

19.8776

22.0791

13

16.2261

16.4821

16.6008

16.9632

17.8333

14

19.8124

20.3238

17.8346

18.9662

21.2454

15

20.9099

21.5762

18.8455

21.0078

22.8969

16

16.0032

16.3796

16.2427

16.9603

17.8581

17

15.9016

16.2572

15.5399

16.9014

16.9627

18

18.0265

18.7282

16.0603

17.1930

19.4643

19

18.1800

18.7034

15.7661

17.3751

19.8848

20

19.8650

20.2711

18.5455

19.8791

21.0384

Acknowledgment

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