在這篇研究中，提出一個可偵測被破壞浮水印並且可回復嵌入資料的方法。 一般浮水印技術都應用在所有權的保護上。 使用者去選擇一張影像的重要區域來當成想保護的感興趣區塊(ROI)，而這些所要保護的ROI我們當成浮水印來藏入在影像當中。 當重要區域遭受到惡意人士的破壞或者捏造時，系統將會偵測出來並且復原重要區域。 系統會經由DCT萃取出這些特徵值，並且對影像執行DWT後把特徵值藏入。 肉眼無法發覺原圖與嵌入後的差異。假如影像遭受到破壞，系統不需要查證於原圖就可以偵測出破壞並且復原ROI。提出的方法不僅簡單而且有效率，另外嵌入特徵值的測試圖被保護的ROI回復的品質也很好。

In this paper, a reversible data embedding for tamper-proof watermarks technique is proposed. In generally, watermarking is used for the purpose of ownership protection. The important regions in the image can be selected by the users as the region of interest (ROI) to protect. And those ROIs are regarded as the watermark and then being embedded in the image. When these important regions are tampered or faked by malicious attacker, the system can detect and recover the ROI. The system extracts the characteristic values by Discrete Cosine Transform (DCT) and embeds those characteristic values into the image by Discrete Wavelet Transform (DWT) to hide those watermarks. The difference between the embedded and original images is invisible by the human eyes. If the image is tampered, the system can detect the tamper and recover the original ROIs. The proposed method is simple but efficient; in addition, the recovered quality of protected ROI is very well from the simulation tests.

摘 要 .......................................I
ABSTRACT ......................................II
誌 謝 ......................................IV
CONTENTS .......................................V
LIST OF FIGURES ......................................VI
LIST OF TABLES........................................................................................VII
CHAPTER 1 INTRODUCTION ......................................1
CHAPTER 2 DCT AND BLOCKY DWT TECHNIQUES.....................................5
2.1 DISCRETE COSINE TRANSFORM (DCT) ......................................5
2.2BLOCKY DISCRETE WAVELET TRANSFORM(DWT) ......................................6
CHAPTER 3 THE PROPOSED SYSTEM ......................................8
3.1 DESCRIPTIONS OF EMBEDDING, TAMPER DETECTION AND RECOVERY SYSTEMS ......................................8
3.2 EXTRACTION OF THE CHARACTERISTIC VALUES ......................................9
3.3 EMBEDDING THE CHARACTERISTIC VALUES ......................................11
3.4 TAMPER DETECTION AND RECOVERY ......................................14
CHAPTER 4 EXPERIMENTAL RESULTS ......................................16
4.1 PROTECTION OF ONE ROI ......................................17
4.2 PROTECTION OF MULTI-ROI ......................................23
4.3 APPLICATION OF MEDICAL IMAGES ......................................26
CHAPTER 5 CONCLUSION ......................................31
REFERENCES ......................................33
PUBLICATION LIST ......................................36

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