由於電腦技術的進步，我們可以將數位化之後的影像以圖形點(pixel)的方式來儲存，但存在許多缺點，因此如何保護重要資料免於被複製、竄改、偷窺和偽造是一個非常重要亟待克服的問題。為了證明影像或圖形是否為合法的擁有與使用，如何驗證影像(image authentication)及圖形的完整性(integration)便成為主要研究的課題，因此我們的研究的主要重點在於如何驗證該張影像或圖形的完整性以及精確地找出被非法竄改的圖形點。在本論文中我們將針對已發表的技術及方法做進一步了解，藉此提出我們的方法—三維偵測法，利用RSA的加密機制將圖形最重要位元所構成的區塊(MSB)透過秘密金鑰加密轉為數位簽章後，放入最不重要位元(LSB)所構成的區塊中，藉由公開金鑰來驗證圖形完整與否，並透過三維偵測法的運算後，偵測出非法竄改點的位置，經由我們的分析與實驗結果，更證明即使在被竄改一個圖形點的情況下，依舊能找出非法竄改點的位置。
除了影像驗證很重要之外，如何事前預防，躲避惡意的竄改攻擊也是急需解決的問題。所以，為了解決網路安全性的問題，當資訊在網路上傳輸時，希望能夠確保不被非法者竊取並解讀。對此，除了在網路系統的安全性加強外，另一個方式就是將傳送的資料隱藏及加密，使資料無法為非法者察覺或解讀。因此，本論文擬針對數位資訊的隱藏做研究，因為在之前的研究當中，對於極少色(few-color)影像的研究相當少，但是這類的圖片卻廣泛的運用在網路上，如卡通圖、二元圖等，所以我們亦提出一個新的方法來隱藏資料於極少色影像中。

As computer technologies advance, we can save digital images by pixels. But it exist many disadvantages, like digital image is easy to copy and modification. So how to protect important data is a serious problem. It is important to protect and verify image integration and copyright. In this paper, we propose an image authentication scheme based on the digital signatures and three-dimension block. Our method used the RSA cryptosystem to generate and put a signature into the least significant bits (LSB) of each block. The proposed scheme can detect and locate the tampered image in one pixel.
In addition to image authentication, it is also important to avoid attacking and tampering, so data hiding and encryption are introduced. The study on data hiding has received great achievement over last several years. However, most of these methods aim at color images and gray images. There were very few researches in few-color images before, but few-color images are widely used in Internet, such as cartoon images, binary images. So we also propose a new method to embed a moderate amount of data in few-color images.

中文摘要 …………………………………………………………………………… i
英文摘要 …………………………………………………………………………… ii
致謝 ………………………………………………………………………………… iii
目錄 ………………………………………………………………………………… iv
表目錄 ……………………………………………………………………………… vi
圖目錄 ……………………………………………………………………………… vii
第一章 概論 ……………………………………………………………………… 1
1.1 數位影像驗證…………………………………………………………… 1
1.2 資訊隱藏………………………………………………………………… 2
1.3 研究動機………………………………………………………………… 3
1.4 論文架構………………………………………………………………… 4
第二章 文獻探討 ………………………………………………………………… 5
2.1 影像驗證技術的相關研究……………………………………………… 5
2.2 資訊隱藏的相關研究…………………………………………………… 6
第三章 驗證影像之完整性—三維偵測法 …………………………………… 9
3.1 研究內容與方法………………………………………………………… 9
3.2 分析……………………………………………………………………… 21
3.3 實驗結果………………………………………………………………… 23
第四章 極少色影像之資訊隱藏 ……………………………………………… 26
4.1 研究內容與方法………………………………………………………… 26
4.2 實驗結果………………………………………………………………… 31
第五章 結論及未來展望 ………………………………………………………… 33
5.1 結論……………………………………………………………………… 33
5.2 未來展望………………………………………………………………… 33
參考文獻 ……………..………………………………………………………… 35
自傳 ……………..……………………………………………..……………… 39

1. D. Atkins, M. Graff, A. K. Lenstra and P. C. Leyland, “The magic words are squeamish ossifrage,” In Advance in Cryptology, Asiacrypt’94, pp. 263-277, Springer-Verlag, 1995.
2. W.bender , N.morimooto, and D.GruhI, “Techniques for data hiding,” IBM System Journal, vol 25,pp.313-335, 1996.
3. C. C. Chang and M. S. Hwang, “Parallel Computation of The Generating Keys For RSA Cryptosystems,” IEE Electronics Letters, vol.32, no.15, pp: 1365-1366. 1996.
4. C. C. Chang, K. F. Hwang, and M. S. Hwang, “A Digital Watermarking Scheme Using Human Visual Effects, “ Informatica, vol.24, no.4, pp: 505-511. 2000.
5. C. C. Chang, M. S. Hwang, and T. S. Chen, “A New Encryption Algorithm For Image Cryptosystems,” Journal of Systems and Software, vol. 58, no.2, pp: 83-91. 2001.
6. T. S. Chen, C. C. Chang, and M. S. Hwang, “A Virtual Image Cryptosystem Based Upon Vector Quantization,” IEEE Transactions on Image Processing, vol.7, no.10, pp: 1485-1488, 1998.
7. G. L. Friedman: “The Trustworthy Digital Camera: Restoring Credibility to the Photographic Image, “ IEEE Trans. on Consumer Electronic, Nov.1993.
8. M. Goljan, J. Fridrich, R. Du, “Distortion-Free Data Embedding for Images,” 4th Information Hiding Workshop, Pittsburgh, Pennsylvania, April 2001.
9. C. S. Huang, C. K. Yang, and D. C. Wu, “A Block Based Digital Watermarking Technique Using Determinant Concept,” CVGIP 2001, pp. 69, 2001.
10. M. S. Hwang, C. C. Chang, and K. F. Hwang, 1999. “A Watermarking Technique Based on One-way Hash Functions,” IEEE Transactions on Consumer Electronics, vol. 45, no.2, pp: 286-294.
11. M. S. Hwang, C. C. Chang, and K. F. Hwang, 2000. “Digital Watermarking of Images Using Neural Networks,” Journal of Electronic Imaging, vol. 9, no.4, pp:548-555.
12.Chang-Tsun Li, Der-Chyuan Lou, Te-Lung Yin, and Jiang-Lung Liu, “Image authentication via image-dependent watermarks,” Proceedings of the ninth national conference on information security, pp 99-102, May 1999.
13. F.A.Petitcolas, R.Anderson, and M.Kuhn, “Information hiding: A survey,” in Proc. IEEE, vol. 87, pp.1062-1078, July 1999.
14. C.Podilchuk and W.Zeng, “Image adaptive watermarking using visual models,” IEEE Journal on Selected Areas in Comm., vol. 16, no. 4, pp.525-539, May1998.
15. G..Pan, Y.J.Wu, and Z.H.Wu, “A novel data hiding method for two-color images,” in Lecture Notes in Computer Science, vol2229,pp: 261 - 270, Oct. 2001,.
16. G..Pan, Y.H.Pan, and Z.H.Wu, “A data hiding method for few-color images.” in Acoustics, Speech, and Signal Processing, 2002. Proceedings. (ICASSP ''02). IEEE International Conference on , vol 4, pp: IV-3469 -IV-3472 , 2002.
17. R. L. Rivest, “The MD5 message digest algorithm,” RFC1321, April 1992.
18. R. L. Rivest, A. Shamir, and L. Adleman, “A method for obtaining digital signatures and public-key cryptosystems,” Communications of the ACM, vol. 21, pp. 120-126,February 1978.
19. B. Schneier, “Applied cryptography,” Proc. IEEE Intl. Conf. On Image Processing, pp.42-48, 1996.
20.Yuan-Liang Tang, Min-Shiang Hwang, Ching-Rong Yang, “An Image Authentication Scheme Based On Digital Signatures,” Pakistan Journal of Applied Sciences, vol. 2, no. 5, pp. 553-557, May 2002.
21. Y.C.Tseng and H.K.Pan, “Secure and invisible data hiding in 2-color images,” in Proc. IEEE INFORM 2001, pp887-896 , 2001.
22. R. B. Wolfgang and E. J. Delp, “A Watermarking Technique for Digital Imagery: Further Studies,” Proceedings of the International Conference on Imaging Science, Systems, and Technology, pp. 279-287, Las Vegas, 1997.
23. D. C. Wu and W. H. Tsai, “Spatial-domain Image Hiding Using Image Differencing,” IEE Proceedings on Vision, Image and Signal Processing, Vol.147, No. 1, pp. 29-37, February 2000.
24. M. Wu and B. Liu, “Watermarking for Image Authentication,” Proc. IEEE Intl. Conf. On Image Processing, pp.437-441, Chicago, USA, Oct.1998.
25. M. Wu, E. Tang, and B. Liu, “Data Hiding in Digital Binary Image,” IEEE International Conference on Multimedia & Expo 2000(ICME’00) New York, New York City, 2000
26. P. W. Wong, “A Public Key Watermark for Image Verification and Authentication,” Proc. IEEE Intl. Conf. On Image Processing, pp.455-459, Chicago, USA, Oct.1998.
27. M.Y. Wu and J.H. Lee, “A novel data embedding method for two-color facsimile images,” in Proc. Int. Symposium on Multimedia Information Processing, Dec.1998.
28. Ching-Rong Yang, Min-Shiang Hwang, Yuan-Liang Tang, “偵測影像的被破壞點之研究--縱橫偵測法,” Eighth National Conference on Science and Technology of National Defense, Tao-Yuan, Nov. 1999.
29. 唐元亮,蔡中瑋,黃明祥, “電子影像完整性之偵測技術,”第二屆管理學域學術研討會, pp.177-182, Taichung, May 8, 2001.