臺灣博碩士論文加值系統

由於網路的發達及其方便性，數位影像傳輸也隨之變得頻繁，其中PNG影像是當今應用相當廣泛的一種影像格式。在本論文中，我們針對PNG影像提出了幾種資訊隱藏的技術與應用，包括版權保護、秘密分享及秘密傳輸。在版權保護部份，我們提出一個基於固定大小區塊的影像驗證方法，讓我們調整影像中紅綠藍色及透明通道的像素值，使其符合某種限制條件，來作為驗證訊號，並用以驗證影像之真假性及完整性。在秘密分享方面，我們提出一種藉由解聯立方程式來達到秘密分享效果之方法，該法由n 讣汹1張使用者自選的掩護影像(cover image)產生n份分享檔案，並且將這n份分享檔案藏進掩護影像的透明通道中，形成n份偽裝影像(stego-image)。我們可以藉由收集n張偽裝影像中的分享檔案來復原原本的秘密。在秘密傳輸部分，我們根據以上提到的驗證和秘密分享之技術提出了兩種資訊隱藏的方法。另外，我們亦結合驗證和資訊隱藏，提出一種可驗證秘密資訊之方法。最後，我們以實驗結果證明了所提方法之可行性。

With the convenience and fast speed on the Internet, exchanges of multimedia become more and more frequent nowadays. PNG images are used in a wide variety of applications. In this study, we propose several methods for data hiding applications via PNG images, including copyright protection, secret sharing, and covert communication. For copyright protection, we propose a block-based method for file authentication, which can authenticate the integrity and fidelity of PNG images by adjusting pixel values to meet some constraints in the three color channels (red, green, and blue) and the alpha channel. For secret sharing, we propose a method by solving three simultaneous equations to generate n shares from n 讣汹轨 cover images, and embedding the shares in the alpha channels of the color images. We can recover the secret by collecting all the shares. For covert communication, we propose two data hiding methods which are based on the proposed authentication method and the proposed secret sharing method. We also apply the two methods to yield a combined data hiding and authentication method to authenticate hidden data. Good experimental results show the feasibility of the proposed methods.

ABSTRACT (Chinese) i
ABSTRACT (English) ii
ACKNOWLEDGEMENTS iii
CONTENTS iv
LIST OF FIGURES vi
Chapter 1 Introduction 1
1.1. Motivation of Study 1
1.2. Overview of Proposed Methods 2
1.2.1 Definitions of Terms 2
1.2.2 Brief Descriptions of Proposed Methods 3
1.3. Contributions 5
1.4. Thesis Organization 6
Chapter 2 Review of Related Works and Standards 7
2.1. Introduction 7
2.2. Previous of Studies on File Authentication Techniques via Digital Images 7
2.3. Previous of Studies on Secret Sharing Techniques 8
2.4. Previous of Studies on Information Hiding Techniques via Digital Images 8
2.5. Review of PNG Standard 9
2.5.1 Usages of PNG Images 9
2.5.2 Properties of PNG Images 10
Chapter 3 Authentication of PNG Images by Adjusting Selected Pixel Values in Spatial Domain and Its Application to Data Hiding 12
3.1. Introduction 12
3.1.1 Problem Definition 12
3.1.2 Proposed Ideas 13
3.2. Proposed Image Authentication And Data Hiding Methods 14
3.2.1 Authentication Signal Embedding Process 14
3.2.2 Image Authentication Process 17
3.3. Proposed Image Hiding Technique Based on Proposed Authentication Method 19
3.3.1 Data Hiding Process 19
3.3.2 Data Extraction Process 21
3.4. Combination of Proposed Authentication Method and Data Hiding Method 23
3.5. Experimental Results 27
3.6. Discussions and Summary 31
Chapter 4 Secret Sharing of Multimedia Information with Steganographic Effect via PNG Images by Solving Simultaneous Equations 33
4.1. Introduction 33
4.2. Proposed Secret Sharing Method 34
4.2.1 Proposed Secret Sharing Process 34
4.2.2 Proposed Secret Multimedia Recover Process 38
4.3. Experimental Results 40
4.4. Discussions and Summary 41
Chapter 5 Data Hiding in PNG Images for Covert Communication 49
5.1. Introduction 49
5.2. Problem Definition 49
5.2.1 Proposed Idea 49
5.3. Proposed Data Hiding Method 51
5.3.1 Proposed Embedding Process 51
5.3.2 Proposed Data Extraction Process 55
5.4. Experimental Results 58
5.5. Discussions and Summary 63
Chapter 6 Conclusions and Suggestions for Future Works 64
6.1. Conclusions 64
6.2. Suggestions for Future Works 65
References 67

[1] C. T. Wang and W. H. Tsai, “Data hiding in PDF files and applications by Imperceivable modifications of PDF object parameters,” Proceedings of 2008 Conference on Computer Vision, Ilan, Taiwan, Aug. 2008.
[2] L. Y. Weng and W. H. Tsai, “Integrity authentication of grayscale document images surviving print-and-scan attacks,” Proceedings of 2005 Conference on Computer Vision, Graphics and Image Processing, Taipei, Taiwan, June 2005.
[3] P. M. Huang and W. H. Tsai, “Copyright protection and authentication of grayscale images by removable visible watermarking and invisible signal embedding techniques: a new approach,” Proceedings of 2003 Conference on Computer Vision, Graphics and Image Processing, Kinmen, Taiwan, pp. 276-283, 2003.
[4] Y. C. Chiu and W. H. Tsai, “Copyright protection by watermarking for Color Images against Rotation and Scaling Attacks Using Peak Detection and Synchronization in Discrete Fourier Transform Domain,” Proceedings of Third Workshop on Digital Archives Technologies, Taipei, Taiwan, pp. 207-213, Aug. 2004.
[5] I. S. Lee and W. H. Tsai "Security protection of software programs by information sharing and authentication techniques using invisible ASCII control codes," International Journal of Network Security, vol. 10, no. 1, pp. 1-10, Jan. 2010.
[6] C. C. Lin and W. H. Tsai “Secret image sharing with steganography and authentication,” Journal of Systems & Software, vol. 73, no. 3, pp. 405-414, Nov.-Dec. 2004.
[7] A. Shamir, “How to share a secret,” Communications of Association for Computing Machinery , vol. 22, no. 11, pp. 612- 613, Nov. 1979.
[8] G. R. Blakley, “Safeguarding cryptographic keys,” Proceedings of the National Computer Conference, New York, U. S. A., pp. 313–317, 1979.
[9] C. C. Lin and W. H. Tsai, “Secret multimedia information sharing with data hiding capacity by simple logic operations,” Proceedings of 5th World Multiconference on Systemics, Cybernetics, and Informatics, Vol. I: Information Systems Development, Orlando, Florida, U. S. A., pp. 50-55, July 2004.
[10] Cramer, et al., “On codes, matroids, and secure multiparty computation from linear secret-sharing schemes”, IEEE Transactions on Information Theory, vol. 54, no. 6, pp. 2644-2657, June 2008.
[11] I. S. Lee and W. H. Tsai, "Data hiding in grayscale images by dynamic programming based on a human visual model," Pattern Recognition, vol. 42, no. 7, pp. 1604-1611, July 2009.
[12] C. H. Lai and W. H. Tsai, “Data hiding by stacking up two PNG images,” Technical Report, Department of Computer Science, National Chiao Tung University, Hsinchu, Taiwan, June 2007.
[13] Ni, et al., “Reversible data hiding,” IEEE Transactions on Circuits and Systems for Video Technology, vol. 16, no. 3, pp. 354-362, Mar. 2006
[14] T. Y. Liu and W. H. Tsai “Robust watermarking in slides of presentations by blank space coloring: a new approach,” accepted and to appear in LNCS Transactions on Data Hiding and Multimedia Security, 2009.
[15] T. Y. Liu and W. H. Tsai "A new steganographic method for data hiding in Microsoft Word documents by a change tracking technique," IEEE Transactions on Information Forensics and Security, vol. 2, no. 1, pp. 24-30, Mar. 2007.
[16] I. S. Lee and W. H. Tsai "Data hiding in binary images with distortion-minimizing capabilities by optimal block pattern coding and dynamic programming techniques," IEICE Transactions on Information and Systems, vol. E90-D, no. 8, pp. 1142-1150., July 2007.
[17] J. Jiang and A. Armstrong “Data hiding approach for efficient image indexing,” IEE Electronics Letters, vol. 38, no. 23, pp.1424-1425, Nov. 2002.