數位浮水印(digital watermarking)是用來捍衛智慧財產權(copyright)的一項技術，但是傳統數位浮水印通常會受限於無法藏入大量資訊與隱藏不易的缺陷。
在本篇論文中，我們提出了一個有效提升浮水印容量的技巧，可以廣泛應用於現今數位浮水印技術上。我們利用掩護媒體各資料間之相關資訊來嵌入(embedding)更多的資料於掩護媒體(cover-media)之中，並提出一個可以在對該掩護媒體品質最少影響下來藏入更多資訊的方法。
最後我們應用兩個浮水印技術來加以實驗分析，證明可以有效提昇藏入浮水印之容量，而且對原掩護媒體品質並不會有太大的影響。

Digital watermarking technology is a potential future technology, which uses to protect copyright. Traditional digital watermarking is usually suffered from the limited information capacity and imperceptibility deficiency.
In this research, we present the method to increase the capacity of the traditional watermarking techniques, which can be used broadly in present digital watermarking techniques by using the relation between the information in the cover-media.
We use two kinds of digital watermarking techniques to analysis. The experiment result show that the proposed method can increase the capacity of embedding information without involves significant quality degradation in cover-media.

Chapter I Introduction 4
1.1 Research Background 4
1.2 Research Motivation 5
1.3 Research Goal 6
1.4 Chapter Description 7
Chapter II Background 8
2.1 The Researches of Digital Watermarking Techniques 8
2.1.1 Spatial Domain 10
2.1.2 Frequency Domain 11
2.2 The Requirements for Digital Watermarking 13
2.3 The Bottleneck of Digital Watermarking 14
2.4 The Application of Digital Watermarking 15
Chapter III The Method to Increase the Capacity of Digital Watermarking 17
3.1 Traditional Digital Watermarking Techniques and its Capacity 17
3.2 Effect and Improvement for the Cover-Media 18
3.3 The Method to Increase the Capacity of Digital Watermarking 25
Chapter IV Experiment Result 33
4.1 Experiment Result 33
4.1.1 Applied on JPEG Hiding Technique 33
4.1.2 Applied on Watermarking Using Zerotree of DCT 35
Chapter V Conclusion and Future Work 41
5.1 Conclusion and Future Work 41
Chapter VI References 43

[1]. E. Adelson, “Digital Signal Encoding and Decoding Apparatus,” U.S. Patent, No. 4939515,1990.
[2]. Van Schyndel, R. Tirkel, A. and Osbourne, ”A digital watermark,” ICIP 94.
[3]. Matsui, K, and Tanaka, K, ”Video-steganography:How to embed a signature in a picture,” IMA Interllectual property project processing, pp.187-206, Jan, 1994.
[4]. A. H. Tewfik and M. Swanson, ”Data hiding for multimedia personalization, interaction and protection,” IEEE Signal Processing Magazine, Vol. 2, pp. 86-90, 1994.
[5]. I. Pitas, ”A method for signature casting on digital images,” Proceedings of IEEE International Conference on Image Processing,” Vol. 3, pp.215-318 ,1996.
[6]. R. Wolfgang and E. Delp, ” A watermark for digital images,” Proceeding of IEEE International Conference on Image Processing, Vol. 2, pp.319-222, 1996.
[7]. G. Voyatzis and I. Pitas, "Chaotic mixing of digital images and applications to watermarking," in Proceedings of European Conference on Multimedia Applications, Services and techniques (ECMAST '96), Vol.2, pp.687-695, May, 1996.
[8]. G. Voyatzis and I. Pitas , "Embedding robust watermarks by chaotic mixing,” in Proceedings of 13th International Conference on Digital Signal Processing (DSP’97), Vol. 1, pp.213-216, 1997.
[9]. G. C. Langelaar, J. C. A. van der Lubbe, and R.L. Lagendijk, ”Robust labeling methods for copy protection of images,” in Proceedings of SPIE Electronic Imaging'97, Storage and Retrieval for Image and video Database V, pp.298-309,San Jose(CA) Feb1997.
[10]. K. I. Hashida and A. Shiozaki, ”A method of embedding robust watermarks into digital color images,” IEICE Transactions on Fundamentals of Electronics , Vol. E81-A, pp.2133-2137, Oct, 1998.
[11]. I. J. Cox, J. Ki1ian, F. T. Leighton, and T. Shamoon, "Secure spread spectrum watermarking for multimedia," IEEE Transactions on Image Processing, Vol.6, No.12, pp.1673-1687,1997.
[12]. 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, Oct, 1998.
[13]. H. INOUE, A. MIYAZAKI and A. YAMAMOTO, "A digital watermarking based on the wavelet transform and its robustness on image compression," Proceeding of IEEE International Conference on Image Processing, Vol. 2, pp.391-395, 1998.
[14]. C. T. Hsu and J. L. Wu, ”Hidden digita1 watermarks in images," IEEE Transactions on Images Processing, Vo1.8, pp.58-68, Jan, 1999.
[15]. F. A. P. Petitcolas, “Digital watermarking & steganography – companies & products,” http;//www.cl.cam.ac.uk/fapp2/steganography/products.html.
[16]. Y. K Lee and L. H. Chen, “JPEG Hiding Technique,” http://debut.cis.nctu.edu.tw/ ~yklee/Research/DataHiding/DataHiding5.htm.
[17]. C. F. Wu and W. S. Hsieh, “Digital watermarking Using Zerotree of DCT,” IEEE Transactions on Consumer Electronics. Vol. 46, No. 1, pp.87-94, Feb, 2000.
[18]. Jerome M. Shapiro, “Embedded Image Coding Using Zerotree of Wavelet Coefficients,” IEEE Transaction on Signal Processing, vol.41, pp.3445-3462, December 1993.