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Source:International Conference on Intelligent Information Hiding and Multimedia Signal Processing (IIH-MSP),2010

Sixth. Authors:Hsiang-Cheh Huang, Yueh-Hong Chen,

and I-Hung WangSpeaker:Cheng Hsu

Date:2011/05/05

Reversible Data Hiding with Improved Histogram Alteration Method

Reversible Data Hiding with Improved Histogram Alteration Method

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Outline

1. Introduction

2. Related work

3. Proposed scheme

4. Experimental results

5. Conclusions

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1. Introduction

Reversible data hiding:1. Histogram-based scheme.

2. Difference expansion (DE) scheme.

They consider the easily implemented algorithm, called histogram-based scheme in reversible data hiding, and they modify the difference between adjacent pixels for making data hiding possible.

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4

2. Related work

Original histogram

Peak point

Zero point

154155152

155153157

154156154

Original image

154156152

156153158

154157154

Cover image

shift

Cover image histogram

0152 153 154 155 156 157 158

123

45678

Embedding procedure

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5Cover image histogram

S = 1 1 0

P’= P + 1

P’= P

If S=1 embedded in 155If S=0 embedded in 154

154156152

156153158

154157154

Cover image

Stego image histogram

0152 153 154 155 156 157 158

123

45678

156152

156153158

157155

Stego image

154

154

155

154

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6Cover image histogram

154156152

156153158

155157155

Stego image

Extracted procedure

S = 1P = P’ - 1

S = 1P = P’ - 1

P = P’ S = 0

S = 1 1 0

154156152

156153158

155157155

Cover image

154 154

154

156

157 155

155

Original image

0152 153 154 155 156 157 158

123

45678

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3. Proposed scheme

111 NMi , ppd iii

Difference：

11981991111 ppd

11992002122 ppd

198 199

202 200

200 201

203 204

198 199 200 202 200 201 204 203

Peak point

Zero point

0

1

2

3

10 2 3 4-1-2

Original difference histogram

Original image

Embedding procedure

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If S=0 embedded in 1

If S=1 embedded in 0

S = 1 0

If S = 1 d’ = d - 1

If S = 0 d’ = d

1

2

3

10 2 3 4-1-2

Original difference histogram

204203

201200

200202

199198

Original image

198 198

202 200

200 201

203 204

200

0

198198

200202

201200

204203Inverse S-type scan

Stego image

d = 1

d = 1

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203 204

200 201

202 200

198 198

Stego image

Extraction procedure

Inverse S-type scan

204203

201200

200202

198198

1

2

3

10 2 3 4-1-2

Stego image difference histogram

If d’ = 0

d = d’ + 1 S = 1

If d’ = 1

d = d’ S = 0

199

200

Original image

P = p’ + d = 198 + 1 = 199

P = p’ + d = 200 + 0 = 200

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4. Experimental results

The image quality and the number of modified blocks under a fixed number of capacity.

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Comparisons between maximal capacity and that in [2].

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5. Conclusions

In this paper, they proposed an improved reversible data hiding scheme by modifying the histogram of original image with its inherent characteristics.

In comparison with conventional scheme [2], more capacity with their scheme can be embedded.

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