Reversible Data Embedding Using Reduced Difference Expansion Intelligent

Reversible Data Embedding Using Reduced Difference Expansion Intelligent Information Hiding and Multimedia Signal Processing, 2007. IIHMSP 2007. Third International Conference on Volume 1, 26 -28 Nov. 2007 Page(s): 433 – 436 Chiang-Lung Liu; Der-Chyuan Lou; Chien-Chung Lee Reporter: Chien-Ting Kuo

Outline n The Proposed Scheme q Embed Watermark q Retrieve Watermark q Restore Host Image n Experimental Results n Conclusions

The Proposed Scheme 隱藏方法： Watermark bits 100 101 99 105 difference 111 100 1 -1 5 Embed Stego Block 100 101 100 105 0 5

Embed Watermark Cover image 100 101 100 106 99 105 102 105 100 121 100 101 98 111 99 150 預計藏入資料： 001 Cover encrypt Watermark Stego

Embeddable Thr = 0 101 100 1 99 -1 5 100 106 100 6 102 105 2 5 100 121 1 100 21 98 0 -2 111 100 101 100 1 99 -1 150 Not Embeddable Changeable 50 20 40 Embeddable 第一種 1 Changeable 第二種 0 Not Embeddable 不藏 分辨種類 原本第二 種的LSB 實際藏的資訊 Watermark = 110 101 001

Embeddable Thr = 0 101 100 1 99 -1 105 100 106 2 100 21 98 -2 100 101 99 150 不藏 第一種 5 100 121 111 40 20 5 100 6 102 105 Not Embeddable Changeable 11 100 3 100 103 -1 99 100 13 4 第二種 10 100 113 11 104 111 100 20 100 120 -2 98 11 111 Watermark = 110 101 001

Cover image Stego image 100 101 100 106 100 103 100 113 99 99 105 102 105 110 104 111 100 121 100 101 100 120 101 98 98 111 99 藏入資料： 001 150 111 99 150

Retrieve Watermark Embeddable 100 103 100 3 99 -1 10 100 113 104 111 0 Not Embeddable Changeable Thr = 20 40 100 13 4 11 Watermark = 110 101 001 100 120 100 20 98 -2 111 11 100 101 100 1 99 -1 50 150 decrypt Stego Watermark

Restore Host Image 100 103 100 3 99 -3 10 100 113 104 111 100 13 4 100 20 98 -2 11 100 101 100 1 99 -1 50 1 100 101 5 99 6 100 106 5 102 105 第二種 100 21 100 121 -1 第一種 100 11 100 120 111 第一種 100 2 -2 不藏 11 98 105 111 Stego Watermark = 110 101 001 recover Cover

Restore Host Image Host image 100 101 100 106 99 105 102 105 100 121 100 101 98 111 99 150

Experimental Results 22. 76 d. B 21. 20 d. B

Conclusion n An Novell Reversible data hiding scheme n Capacity depends on the image n The idea of “reversible” is valuable