臺灣博碩士論文加值系統

在資訊隱藏技術中，較為大家所熟知的是隱藏學與數位浮水印，其差別在於數位浮水印嵌入的資料與掩護資料有關係，而隱藏學則否。對於數位浮水印，我們可將它分成以強韌性或是以易碎性為主兩種，其目的為著作權的保護以及利用數位浮水印來做認證。然而在隱藏學，我們所關心的則是資料隱藏量以及藏入資料後的不被察覺能力。資訊隱藏技術近年來被廣泛的應用於錯誤回復影像編碼技術中。影像的重要資訊利用資訊隱藏的技術藏回原影像，並且不造成原影像的損失。當解碼時這些重要的影像資訊可以被取回用來回復影像時使用。這種錯誤影像回復編碼在無線影像通訊與影像壓縮這些對錯誤很敏感的應用有極大的價值。在此篇論文中，我們研究資訊隱藏並專注於資訊隱藏量的提升，並同時讓藏完訊息的影像有不被察覺差異的能力: (一) 在人眼視覺系統下有可接受的影像品質，讓一般人看不出差異 (二) 利用運算分析做統計攻擊時也有不被察覺的能力。
近年來，一些針對影像上的資訊隱藏，有很多採用像素差異與非均勻量化的技術。利用這些技術可以克服統計分析攻擊並有不被人眼視覺系統察覺的能力。一般而言，差異選取的方式與量化階度的選擇會造成隱藏量與不可察覺性兩方面的衝突，因為隱藏量越多，所影響影像品質的程度也越大。在本篇論文中，我們提出一種基於空間填充曲線的像素差異資訊隱藏技術，並從一般影像特性統計出適合於填充曲線像素差異值的量化階度。最後，我們提出的方法，不僅提升了資訊隱藏量，與先前的方法相比，在人眼視覺系統下有較佳的不被察覺能力，以及可抵抗統計分析攻擊的能力。

Steganography and digital watermarking are two well-known subjects in information hiding techniques. Digital watermarking is dedicated on robustness and fragility, and is usually used for copyright protection and authentication. However, steganography is aimed at the high embedding capacity and the imperceptibility. Recently, steganography is widely used in error-resilient image coding schemes which embed the important data of image into the same image such that the image quality is not degraded much; also the important data can be extracted for error resiliency when decoding. This error-resilient image coding is often applied in wireless image transmission and the compressed image/video bitstream which is very sensitive to bit errors.
Recently, many steganography methods for images based on pixel-value differencing and non-uniform quantization techniques were proposed. All schemes are possessed of the imperceptibility by human visual system but some of them will be compromised by the stegoanalysis. In this thesis, we study steganography technique and address enhancing the embedding capacity and simultaneously provide the good imperceptibility (the imperceptibility for human and the imperceptibility for computer, i.e. against stegoanalysis). The selection of difference and quantization range will result in a trade-off between the embedding capacity and imperceptibility. In this thesis, we introduce a new pixel-value differencing scheme based on space filling curve to achieve the high embedding capacity. By analyzing the property of image, we choose an appropriate quantization for the pixel difference when using the space filling curve. Finally, our proposed framework enhances the embedding capacity when compared all previous pixel-difference based schemes. Also, our scheme has the imperceptibility by human visual system and the capability against stegoanalysis.

Chpater 1 Introduction 1
1.1 Background 1
1.2 Motivation 2
1.3 Contributions 3
1.4 Organization of the Thesis 4
Chpater 2 Steganography Schemes Using Pixel-Value Differencing 5
2.1 The Wu-Tsai Pixel-Value Differencing Scheme 7
2.2 The Chang-Tseng Side-Match Scheme 9
2.3 The Yang-Weng Multi-Pixel Differencing Scheme 10
2.4 Analysis of Chang-Tseng Side-Match Scheme 11
Chpater 3 The Proposed Steganography Schemes 15
3.1 Design Concept 15
3.2 The Proposed Steganography Scheme 18
3.3 Block-Wise Effect in the Proposed Scheme 21
3.4 Theoretical Estimation for Embedding Capacity and PSNR of Stegoimage 23
Chpater 4 Experiment and Comparison 27
4.1 Choice of Test Images 27
4.2 Experimental Results and Comparison 28
Chpater 5 Conclusion and Future Work 37
Appendix 39
References 43

[ARTZ01]D. Artz, “Digital Steganographic: Hiding data within data,” IEEE Internet Comput., Vol. 5, pp. 75–80 2001.
[CHAN04A]C.K. Chan, L.M. Chen, “Hiding data in images by simple LSB substitution,” Pattern Recognition, Vol. 37-3, pp. 469–474 2004.
[CHAN02]C.C. Chang, K.F. Hwang, M.S. Hwang, “Robust authentication scheme for protecting copyrights of images and graphics,” IEEE Proceedings on Vision, Image and Signal Processing Vol. 149, No. 1. 2002.
[CHAN03]C.C. Chang, J.Y. Hsiao, C.S. Chan, “Finding optimal least-significant-bit substitution in image hiding by dynamic programming strategy,” Pattern Recognition, Vol. 36-7, pp. 1583–1595 2003.
[CHAN04B]C.C. Chang, W.H. Tseng, “A steganographic method for digital images using side match,” Pattern Recognition Letters, Vol. 25, pp. 1434–1437 2004.
[CHAN06]C.C. Chang, C.Y. Lin, Wang, Y.Z., “New image Steganographic methods using run-length approach,” Information Sciences, Vol. 176, No. 22, pp. 3393-3408 2006.
[CHAN04C]C.K. Chan, L.M. Chen, “Hiding data in images by simple LSB substitution,” Pattern Recognition, Vol. 37-3, pp. 469–474 2004.
[COX97]I.J. Cox, J. Kilian, F.T. Leighton, T. Shamoon, “Secure spread spectrum watermarking for multimedia,” IEEE Trans. Image Process., Vol. 6, pp. 1673–1687 1997.
[COX00]I.J. Cox, M.L. Miller, J.A. Boom, “Watermarking applications and their properties,” Proc. Internat. Conf. on Information Technology: Coding and Computing, pp. 6–10 2000.
[COX01]I.J. Cox, J.A. Bloom, M.L. Miller, “Digital watermarking: principles & practice,” 2001.
[FRID98]J. Fridrich, 1998. Image watermarking for tamper detection. Proc. IEEE Internat. Conf. on Image Processing, Vol. II, pp. 404–408.
[FRID00]J. Fridrich, D. Rui, “Secure steganographic methods for palette images,” Proc. Third Internat. Workshop Information Hiding, Lecture Notes in Computer Science, Vol. 1768, pp. 61–76 2000.
[FIRD01]J. Fridrich, M. Goljan, R. Du, “Detecting LSB steganography in color, and gray-scale images,” IEEE Multimedia, Vol. 8, 22–28 2001.
[FRID02]J. Fridrich, M. Goljan, “Practical steganalysis of digital images-state of the art,” Proc. SPIE Photonics West, Conference on Security and Watermarking of Multimedia Contents, Vol. 4675, pp. 1–13 2002.
[HART99]F. Hartung, M. Kutter, “Multimedia watermarking techniques,” Proc. IEEE, Vol. 87, pp. 1079–1107 1999.
[LEE00]Y.K. Lee, L.H. Chen, “High capacity image steganography,” IEE Proceedings on Vision Image, and Signal Processing, Vol. 147, pp. 288–294 2000.
[LIE99]W.N. Lie, L.C. Chang, “Data hiding in images with adaptive numbers of least significant bits based on the human visual system,” Proc. IEEE Internat. Conf. Image Process, Vol. 1, pp. 286–290 1999.
[PETI99]F. A. P. Petitcolas, R. J. Anderson, M. G. Kuhn, "Information hiding-a survey," Proceedings of the IEEE, vol. 87, pp. 1062-1078 1999.
[SWAN98]M.D. Swanson, M. Kobayashi, A.H. Tewfik, ”Multimedia data-embedding and watermarking technologies,” Proc. IEEE, Vol. 86, pp. 1064–1087 1998.
[TSEN04]H. Tseng and C. Chang, “High capacity data hiding in JPEG-compressed images,” Informatica, vol. 15, pp. 127–142 2004.
[VOYA99]G. Voyatzis, I. Pitas, “The use of watermarks in the protection of digital multimedia products,” Proc. IEEE, Vol. 87, pp. 1197–1207 1999.
[WANG00]R.Z. Wang, C.F. Lin, J.C. Lin, “Image hiding by optimal LSB substitution and genetic algorithm,” Pattern Recognition, Vol. 11-3, pp. 71–683 2000.
[WEST00]A. Westfeld, A. Pfitzmann, “Attacks on steganography systems,” Proc. Third Internat. Workshop Information Hiding,” Lecture Notes in Computer Science, Vol. 1768, pp. 61–75 2000.
[WOLF99]R.B. Wolfgang, C.I. Podilchuk, E.J. Delp, “Perceptual watermarks for digital images and video,” Proc. IEEE, Vol. 87, pp. 1108–1126 1999.
[WU03] D.C. Wu, W.H. Tsai, ”A steganographic method for images by pixel-value differencing,” Pattern Recognition Letters, Vol. 24, pp. 1613–1626 2003.
[XUAN02]G. Xuan, J. Zhu, J. Chen, Y.Q. Shi, Z. Ni, and W. Su, “Distortionless data hiding based on integer wavelet transform,” Electron. Lett., vol. 38, pp. 1646–1648 2002.
[YANG06A]C.H. Yang, S.J. Wang, “Weighted bipartite graph for locating optimal LSB substitution for secret embedding,” Journal of Discrete Mathematical Sciences & Cryptography, Vol. 9-1, pp. 153–164 2006.
[YANG06B] C.H. Yang, C.Y. Weng, “A steganographic method for digital images by multi-pixel differencing,” International Computer Symposium 2006, pp. 831–836 2006.