基於分碼多重存取及離散小波轉換之浮水印技術

CDMA-based Watermarking Schemes in DWT Domain

王世文(Shih-Wen Wang)

指導教授 ： 黃育銘

國立暨南國際大學/科技學院/資訊工程學系/碩士(2016年)

摘要

近年隨著智慧型裝置及相關應用的蓬勃發展，讓數位資料的產權保護逐漸受到重視，而浮水印技術(Digital Watermarking)便是將所要隱藏的秘密訊息嵌入至載體中，在一般情況下肉眼無法察覺異常，因而達到保護產權的目的。
本文探討藉由分碼多重存取技術(CDMA)將浮水印展頻後嵌入至離散小波轉換域(Discrete Wavelet Transform Domain)之方法，並提出透過預先處理(嵌入變異量(Variance)較小的區塊)及事後估算值來提高已嵌入浮水印之影像品質及增強浮水印之強韌性。

關鍵字

浮水印 ； 分碼多重存取 ； 小波轉換

並列摘要

In recent years, Smart mobile devices have become widely used because of their low cost and user –friendly. Thus it makes the protection of digital data copyrights be taken seriously. The digital watermarking technology means that hiding the secret message (watermark) into the carrier (image or video) that the naked eye of the people cannot perceive any abnormality, and thus to achieve the protection of copyrights.
This dissertation first exploits a method which spreads the watermark by the CDMA technology and hides the spread data in the DWT domain. Next, a variance-reduction technique is proposed to enhance the robustness of watermarking.

並列關鍵字

watermarking ； CDMA ； DWT ； spread spectrum

參考文獻

[1] J. Cox, M. L. Miller, and J. A. Bloom, Digital watermarking, Morgan Kaufmann Publishers, 2002.

[2] R. C. T. Lee, M. C. Chiu, and J. S. Lin, Communications Engineering,Wiley Publishers, 2007.

[3] AaI. J. Cox, J. Kilian, T. Leighton and T. Shamoon, “Secure spread spectrum watermarking for multimedia,” IEEE Trans. on Image Processing, vol. 6, pp. 1673-1687, Dec. 1997.

[4] E. Mwangi, “A wavelet based image watermarking scheme with a CDMA/Hadamard embedding technique,” 9th International Symposium on Signal Processing and Its Applications, pp. 1-4, 2007.

[5] S. P. Maity and M. K. Kundu, “A blind CDMA image watermarking scheme in wavelet domain, ” International Conference on Image Processing, pp. 2633-2636, 2004.