DWT Based Watermarking Algorithm using Haar Wavelet

International Journal of Electronics and Computer Science Engineering 1

Available Online at www.ijecse.org ISSN- 2277-1956

ISSN 2277-1956/V1N1-01-06

DWT Based Watermarking Algorithm using Haar Wavelet

Anuradha 1 , Rudresh Pratap Singh 2

1 2 Department of Electronics and Communication Engineering 1 Laxmi Devi Institute of Technology, Alwar, Rajasthan, India

2 Institute of Engineering and Technology, Agra 1 Email- [email protected]

Abstract- The Development of computer networks enhance the development of the information technology in different areas. Sometimes the digital data can be easily used to copied, modified and distributed in an illegal way. The copy right protection, intellectual protection and material right protection for authors, owners, buyers and distributors is necessary and the authenticity of content or matter are crucial factors to solving problem. In such case the digital watermarking techniques play an important role as a valid solution. In this paper, we introduce a suitable method of watermarking because the watermark protects the copyright of digital products and the integrity of certification. The main focused of Watermarking is developing and introducing new techniques for watermark embedding and detection. Experimental results show that the embedded watermark is transparent and quite robust in face of various watermark images at high compression ratios and provides good results in terms of imperceptibility.

Keywords – Watermarking, Haar Wavelet, DWT, PSNR

I. INTRODUCTION

In recent years, the accessing of multimedia data or digital data has become very easy because of the fast development of the Internet. In other words, this development makes unauthorized distribution of multimedia data. For the protection of multimedia data, a solution known as watermarking is used. After the approximate 20 years’ research, different kinds of watermarking algorithm based on different theory concepts were introduced [1-3]. A digital watermark encodes the owner's license information and embeds it into data. Watermarking may be used to identify the image of owners’ license information and to track illegal copies.

In this paper, a wavelet-based watermarking approach is proposed in which a visually recognizable watermark is added to the wavelet coefficients of an image. This watermark can be a binary, gray-scale. The extracted watermark is visually recognizable to claim ownership. The embedded watermark is hard to detect by human visual perceptivity. In the proposed method pixels of watermark are embedded in wavelet Coefficients corresponding to the points located in a neighborhood with maximum entropy. Embedding the watermark in such pixels makes it possible to use maximum amount of watermark due to human eye insensitivity to areas with high entropy.

In general, a digital watermarking technique must satisfy the following six properties [4] & [5]:

1. it must be invisible. 2. it must not affect the quality of the host (original image to be protected ). 3. it must be easily extracted in a reliable and convenient way. 4. it must take into account the applications to be robust, fragile or semi fragile. 5. it must be resilient to standard manipulations. 6. it must be compatible with the host.

A watermark should not modify or change the information contained in the original image. The protection against change or modify is introduced by the addition of the watermark itself and it is supposed to identify the owner. It is

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often desired to retrieve the embedded information without reference to the host data; this is known as blind watermarking [6].

The rest of the paper is organized as follows. Proposed embedding and extraction algorithms are explained in section II. Experimental results are presented in section III. Concluding remarks are given in section IV.

II. PROPOSED ALGORITHM

A. Watermark embedding algorithm –

In case of two-dimensional image, after a DWT transform, the image is divided into four corners, upper left corner of the original image, lower left corner of the vertical details, upper right corner of the horizontal details, lower right corner of the component of the original image detail (high frequency). You can then continue to the low frequency components of the same upper left corner of the 2nd, 3rd inferior wavelet transform.

Figure 1. DWT Decomposition model

After wavelet decomposition process, the low frequency component is equivalent or similar to the original image, so the band has added to the watermark robustness. So that the low frequency components of the human eye to adding a watermark are much higher than the sensitivity of high frequency components by adding information. On the other hand, by the knowledge of image compression, we know that the adding of watermark in the high frequency image can be easier to lose with lossy compression in the operation. On the basis of such considerations, the algorithm uses a different color image multiplied by the weighting coefficients of different ways to solve the visual distortion, and by embedding the watermark, wavelet coefficients of many ways, enhance the robustness of the watermark.

Figure 2. Watermark embedding algorithm Block Diagram


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After that we select the ordered coefficient from 1 to N to get N coefficient. the formulae of watermark embedding are as follows.

Cw(i) = Yo(i)+α1w(i) Where the parameter α is called embedding intensity and their effect of validity of the algorithm directly is apply

after this process, after that apply the inverse wavelet transform to the image for find out watermark image.

B. Watermark Extraction algorithm –

The extraction algorithm process is the inverse of the embedding process. It is assumed that the watermark as well as the see value is available at the receiver end to the authorized users.

The operation of channel separation is applied on the watermarked color image to generate its sub images, and then 2-level discrete wavelet transform is applied on the sub images to generate the approximate coefficients and detail coefficients.

Figure 3. Watermark Extraction algorithm Block Diagram

After that the similar operation is applied on the original image, and generate it’s both coefficients, first approximate coefficients and second detail coefficients. With the both coefficient approximate coefficients and the detail coefficients of watermarked image and original image, we could extract watermark data through watermark extracting algorithm, respectively. For this purpose the following formulae is use-

W(i) = (yw(i) + yo(i)) / α After this Execution the Inverse 2-level discrete wavelet transform is applied on the watermark data to generate

three watermark images extracted.

III. EXPERIMENT AND RESULT

The test set for this evaluation experiment watermark image randomly selected from the internet. Matlab 7.0 software platform is use to perform the experiment. The PC for experiment is equipped with an Intel P4 2.4GHz Personal laptop and 2GB memory.

The Method discussed in the previous section was applied to various test images. An example of embedding results is shown in figure 4, in which a Lena’s image is used as the test image and a binary image is used as the watermark. PSNR is peak signal to noise ratio which is used to define the accuracy so use the PSNR as the objective

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criteria for watermark to calculate the similarity between extracted waterma6(c) shows the watermarked image. is tested using ordinarily image processing.conclusion that this method is robust to many kinds of watermark

Figure 4. (a) Original image (b)

Figure 5. (a) Original image (b)

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criteria for watermark to calculate the similarity between extracted watermark and original watermark. Fig.4(c), Thus it can be seen that this method has good invisibility. The proposed scheme

processing. From the simulation of the experiment results, we can draw to the robust to many kinds of watermark images.

(a) (b)

(c) (d)

. (a) Original image (b) BJUT watermark Image (c) Watermarked image (d) Recovered watermark Image

(a) (b)

(c) (d)

. (a) Original image (b) Bobbol watermark Image (c) Watermarked image (d) Recovered watermark Image


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rk and original watermark. Fig.4(c), 5(c), Thus it can be seen that this method has good invisibility. The proposed scheme

From the simulation of the experiment results, we can draw to the

BJUT watermark Image (c) Watermarked image (d) Recovered watermark Image

Bobbol watermark Image (c) Watermarked image (d) Recovered watermark Image


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(a) (b)

(c) (d)

Figure 4. (a) Original image (b) DDNT watermark Image (c) Watermarked image (d) Recovered watermark Image

Table -1 Experiment Result

Original Lena Image (PSNR)

Watermarked Lena Image (PSNR)

BJUT Watermark Image

33.1224 41.9946

Bobbol Watermark Image

33.1224 47.5911

DDNT Watermark Image

33.1224 45.8103

Table 1 show the peak signal to noise ratio of performance of our proposed method of watermarked image and

original image with various watermark image, where our watermarked images peak signal to noise ratio has a better performance than others.

IV.CONCLUSION

In our proposed watermarking method, a grayscale visual watermark image is inserted into the host color image using the Haar Wavelet Transform, where the copyright of Watermark is printed. The experimental results have confirmed that this new technique has two properties high fidelity and robust. In our scheme realization and robust experiments, the results prove the feasibility and validity of our proposed scheme. This superiority can greatly contribute to the improvement of watermarking efficiency in the situations which need for Real-time processing such as video image watermarking.


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V. REFERENCE

1. B. Corona, M. Nakano, H. Pérez, “Adaptive Watermarking Algorithm for Binary Image Watermarks”, Lecture Notes in Computer Science, Springer, pp. 207-215, 2004. 2. A. A. Reddy and B. N. Chatterji, "A new wavelet based logo-watermarking scheme," Pattern Recognition Letters, vol. 26, pp. 1019-1027, 2005. 3.P. S. Huang, C. S. Chiang, C. P. Chang, and T. M. Tu, "Robust spatial watermarking technique for colour images via direct saturation adjustment," Vision, Image and Signal Processing, IEE Proceedings -, vol. 152, pp. 561-574, 2005. [4] F. Gonzalez and J. Hernandez, " A tutorial on Digital Watermarking ", In IEEE annual Carnahan conference on security technology, Spain, 1999. [5]D. Kunder, "Multi-resolution Digital Watermarking Algorithms and Implications for Multimedia Signals", Ph.D. thesis, university of Toronto, Canada, 2001. [6] J. Eggers, J. Su and B. Girod," Robustness of a Blind Image Watermarking Scheme", Proc. IEEE Int. Conf. on Image Proc., Vancouver, 2000. [7] Barni M., Bartolini F., Piva A., Multichannel watermarking of color images, IEEE Transaction on Circuits and Systems of Video Technology 12(3) (2002) 142-156. [8] Kundur D., Hatzinakos D., Towards robust logo watermarking using multiresolution image fusion, IEEE Transcations on Multimedia 6 (2004) 185-197. [9] C.S. Lu, H.Y.M Liao, “Multipurpose watermarking for image authentication and protection,” IEEE Transaction on Image Processing, vol. 10, pp. 1579-1592, Oct. 2001. [10] L. Ghouti, A. Bouridane, M.K. Ibrahim, and S. Boussakta, “Digital image watermarking using balanced multiwavelets”, IEEE Trans. Signal Process., 2006, Vol. 54, No. 4, pp. 1519-1536. [11]. P. Tay and J. Havlicek, "Image Watermarking Using Wavelets", in Proceedings of the 2002 IEEE, pp. II.258 – II.261, 2002. [12]. P. Kumswat, Ki. Attakitmongcol and A. Striaew, "A New Approach for Optimization in Image Watermarking by Using Genetic Algorithms", IEEE Transactions on Signal Processing, Vol. 53, No. 12, pp. 4707-4719, December, 2005. [13] . H. Daren, L. Jifuen,H. Jiwu, and L. Hongmei, "A DWT-Based Image Watermarking Algorithm", in Proceedings of the IEEE International Conference on Multimedia and Expo, pp. 429-432, 2001. [14]. C. Hsu and J. Wu, "Multi-resolution Watermarking for Digital Images", IEEE Transactions on Circuits and Systems- II, Vol. 45, No. 8, pp. 1097-1101, August 1998. [15]. R. Mehul, "Discrete Wavelet Transform Based Multiple Watermarking Scheme", in Proceedings of the 2003 IEEE TENCON, pp. 935-938, 2003.

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DWT Based Watermarking Algorithm using Haar Wavelet