Reversible data hiding based on multilevel histogram modification and pixel value grouping Source : Journal of Visual Communication and Image Representation, vol.40, pp.459-469 , October 2016 Authors : Wenguang He , Gangqiang Xiong , Ke Zhou and Jie Cai Speaker : Chia-Shuo Shih Date : 2018/07/19 1

Outline Related work Proposed method Experimental results Conclusion Histogram shifting Proposed method Experimental results Conclusion 2

Related work-Histogram shifting 2 3 4 5 1 Z. Ni, Y.Q. Shi, N. Ansari, W. Su Reversible data hiding IEEE Trans. Circuits Syst. Video Technol., 16 (3) (2006), pp. 354-362 3

Related work-Histogram shifting 2 3 5 6 1 4

Related work-Histogram shifting 2 3 5 6 1 2 3 5 6 4 1 s = 010111001 5

Proposed method-PVG Pixel value grouping(PVG) 6 96 95 94 97 92 98 91 93 91 92 93 94 95 96 97 98 6

Proposed method-PVG 7 T = 4 𝑃 𝐿 ={91} 𝑃 𝑅 ={98} 91 92 93 94 95 96 97 = {91,92} 98-98 = 0 ≤ T = {98,98} 𝑃 𝐿 𝑃 𝑅 𝑃 𝐿 𝑃 𝑅 91 92 93 94 95 96 97 98 7

Proposed method-PVG (1) i + 1 < j 8 T = 4 𝑃 𝐿 𝑃 𝑅 91 92 93 94 95 96 97 98 95-91 = 4 ≤ T = {91,92,93,93,94,94,95,95,95} 𝑃 𝐿 (1) i + 1 < j 𝑃 𝐿 𝑃 𝑅 91 92 93 94 95 96 97 98 8

Proposed method-PVG 9 𝑃 𝐿 𝑃 𝑅 T = 4 15 16 17 18 19 23 25 26 27 = {15,15,16,16,17,18,18,18,18} 27-19 = 8 > T 𝑓 𝑅 = 1 𝑃 𝑅 = {23,25,26,26,26,27,27} 𝑃 𝐿 𝑃 𝐿 𝑃 𝑅 (2) i +1 =j and (𝑓 𝐿 =1 𝑜𝑟 𝑓 𝑅 = 1) 15 16 17 18 19 23 25 26 27 9

Proposed method-PVG 10 T = 4 𝑃 𝐿 𝑃 𝑅 15 16 17 18 19 23 25 26 27 = {15,15,16,16,17,18,18,18,18,19} 𝑓 𝑅 = 1 𝑃 𝐿 𝑃 𝐿 𝑃 𝑅 (2) i +1 =j and (𝑓 𝐿 =1 𝑜𝑟 𝑓 𝑅 = 1) 15 16 17 18 19 23 25 26 27 10

Proposed method-PVG 11 (3) 𝑓 𝐿 =1 𝑎𝑛𝑑 𝑓 𝑅 =1 T = 4 𝑃 𝐿 𝑃 𝑅 60 62 63 67 70 71 72 73 67-60 = 7 > T 𝑃 𝐿 = {60,60,62,62,63} 𝑓 𝐿 = 1 73-71 = 2 ≤ T 𝑃 𝑅 = {71,71,72,73,73,73} 𝑃 𝐿 𝑃 𝑅 (3) 𝑓 𝐿 =1 𝑎𝑛𝑑 𝑓 𝑅 =1 60 62 63 67 70 71 72 73 73-67 = 6 > T 𝑃 𝑅 = {70,70,70,70,71,71,72,73,73,73} 𝑓 𝑅 = 1 𝑓 𝐿 = 1 11

Proposed method-Embedding EL = 4 𝑃 𝐿 𝑃 𝑅 𝑓 𝑅 = 1 𝑓 𝐿 = 0 15 16 17 18 19 23 25 26 27 PVG 23 15 16 27 19 18 25 26 17 15 16 19 18 17 23 27 25 26 𝑃 𝐿 𝑃 𝑅 12

Proposed method-Embedding 15 16 19 18 17 19 -4 -3 -1 -2 𝑝 ref =19 𝑃 𝐿 𝑓 𝐿 = 0 13

Proposed method-Embedding Serect bit: 01000010 15 16 19 18 17 -4 -3 -1 -2 1 15 -> 1 = 10 15 -> 0 = 11 16 -> 1 = 12 16 -> 0 = 13 17 -> 1 = 14 17 -> 0 = 15 18 -> 1 = 16 18 -> 0 = 17 11 13 19 17 10 16 15 14

Proposed method-Embedding 23 27 25 26 22    𝑝 v−ref = 𝑃 σ(n) - (EL+1)   22 = 27 - (4+1) 𝑃 𝑅 𝑓 𝑅 = 1 1 5 3 4 15

Proposed method-Embedding Serect bit: 01101 23 27 25 26 1 5 3 4 1 23 -> 0 = 24 23 -> 1 = 25 24 -> 0 = 26 24 -> 1 = 27 25 -> 0 = 28 25 -> 1 = 29 26 -> 0 = 30 26 -> 1 = 31 25 32 28 30 31 16

Experimental results 17 Image Scheme EL = 1 EL = 3 EL = 5 EL = 7 EC PSNR Lena Proposed 0.14 49.27 0.47 42.71 0.65 39.56 0.73 37.61 0.77 36.38 Luo et al. 0.33 43.33 0.59 38.84 0.7 36.64 0.76 35.23 0.79 34.21 Baboon 0.03 50.65 0.09 44.23 0.17 40.25 0.25 37.38 35.2 42.62 0.19 36.99 0.29 33.86 0.37 31.75 0.43 30.18 Pepper 0.07 49.97 0.28 43.14 0.49 39.2 0.63 36.83 0.72 35.34 0.23 43.03 0.48 38.12 35.72 34.26 33.25 Elaine 0.06 50.21 43.64 0.34 39.59 36.74 0.61 34.69 0.18 42.89 0.38 37.68 0.54 35.01 33.36 0.74 32.26 Boat 50.13 0.22 43.47 39.45 0.51 36.79 34.93 42.88 0.52 34.97 33.23 0.68 31.98 Barbara 0.08 49.98 43.29 39.61 37.21 0.58 35.42 42.9 37.7 34.88 0.55 32.97 0.6 31.53 Comparison of our scheme and Luo et al.’s scheme with 4 × 4 block partition. 17

Experimental results 18

Experimental results 19

Conclusion Pixel Value Grouping(PVG) 20

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