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Content-Dependent Watermarking
Scheme in Compressed Speech
With Identifying Manner and
Location of Attacks
Oscal T.-C. Chen and Chia-Hsiung Liu
Date：2009/12/01
Speaker：Jhang Hon-Bin
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Outline
۞ Introduction
۞ Proposed Scheme
۞ Computer Simulations
۞ Conclusions
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Oscal T.-C. Chen
美國南加州大學電機工程博士
國立中正大學電機工程學系專任教授
Chia-Hsiung Liu
國立中正大學電機工程研究所博士
Received May 31, 2006
Revised January 15, 2007
This work was supported in part
by the National Science Council(NSC), Taiwan, R.O.C.
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Introduction (1/5)
無 浮水印
加入
浮水印
發現攻擊!!
Hacker
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Introduction (2/5)
 Watermarking Scheme
• Robust、Fragile、Semi-Fragile
 Theoretical Foundation of Conventional Watermarks
固定值: Image ID
目前區塊 : Image feature
變異值: block index
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Introduction (3/5)
 Theoretical Foundation of Conventional Watermarks
識別標誌訊息
(Cont.)
鄰近區塊 : Image feature
鄰近區塊 : Image
Watermark
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Introduction (4/5)
 Design Concept (Problem)
• A speech watermarking scheme must reliably determine
where and how attacks take place.
• A deletion and insertion attacks that influence speech
length.
• When a watermarking scheme applies (4) to verify speech
integrity. Cannot localize attacks due to an inconsistency
between
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Introduction (5/5)
 Objective
• 準確地檢測攻擊的 位置 和攻擊的 型態
• 語音壓縮技術使用 G.723.1
• 嵌入浮水印後能保持 語音品質 最小下降
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Proposed Scheme (1/8)
 Design Concept (Solve)
• When a watermarking scheme applies (4) to verify speech
integrity. Cannot localize attacks due to an inconsistency
between
• The first scheme is to constrain the
following equation:
限制
value using the
的範圍
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Proposed Scheme (2/8)
 Design Concept (Solve)(Count.)
• The second scheme,the generating process does not use
data, such as frame index, to generate the watermark
• The second approach is a watermarking scheme expressed as.
特點
The first scheme
可確定在何處以及如何發生攻擊。
The second scheme
只能找攻擊位置，但不能確定攻擊方式。
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Proposed Scheme (3/8)
 Design Concept (Solve)(Count.)
• The two schemes can be integrated into one scheme to
help achieve our goal.
Group
Frame Frame ‧ ‧ ‧
Group
Frame Frame ‧ ‧ ‧
Group
Frame Frame ‧ ‧ ‧
Then (8) is used to generate watermarks.
In most circumstances, (9) is employed to generate
watermarks.
• Determine attack type and localize attacked segments.
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Proposed Scheme (4/8)
 Watermark Generation
三種浮水印產生方式
1. The first frame in a group
2. The last frame of all speech data
3. The other frame in a group
Group g-1
1
‧‧‧
Group g
1
‧‧‧
Last group
‧‧‧
1
‧‧‧
2
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Proposed Scheme (5/8)
 Watermark Generation (Count.)
• The first frame in a group
下一個frame的pitch
由
所產生
是表示group index的位元數
目前frame的LSF
前一個group的最後一個frame
Group g-1
‧‧‧
Group g
‧‧‧
Last group
‧‧‧
‧‧‧
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Proposed Scheme (6/8)
 Watermark Generation (Count.)
• The last frame of all speech data
前一個frame
是最後一個group的frame數
是表示pitch feature的位元數
目前frame的LSF
Group g-1
‧‧‧
Group g
‧‧‧
Last group
‧‧‧
‧‧‧
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Proposed Scheme (7/8)
 Watermark Generation (Count.)
• The other frame in a group
前一個frame
Group g-1
‧‧‧
目前frame的LSF
Group g
‧‧‧
下一個frame的pitch
Last group
‧‧‧
‧‧‧
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Proposed Scheme (8/8)
原浮水印
產生浮水印Comparator
& 嵌入浮水印
取出的浮水印
Correct
Or
Incorrect
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2
1
ITUT G.723.1
MP-MLQ (6.3 k bit/s)
60
1 frame = 240
60
取出浮水印 60
60
04 / 23 / 2009 P 16
Computer Simulations (1/8)
 Evaluation of Speech Quality
• Eleven conversations of 60.6 ~125.6 s are encoded.
表3.1 :正常語音壓縮和加入浮水印後PESQ數值
PESQ
正常語音壓縮
加入浮水印
3.52
3.41
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Computer Simulations (2/8)
 Comparison Between Proposed and Conventional Schemes
• The schemes proposed by Yuan et al. and Steinebach et al.
are rederived from (5)–(7) to (15)–(17), respectively
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Computer Simulations (3/8)
表3.2 : 三種浮水印攻擊對原 2019 frames 語音的影響
攻擊方式
影響frame範圍
影響frame個數
替代
343~680
338
插入
1129
239
刪除
1675~1694
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Computer Simulations (4/8)
 The Watermarking Scheme Based on (15)
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Computer Simulations (5/8)
 The Watermarking Scheme Based on (16)
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Computer Simulations (6/8)
 The Watermarking Scheme Based on (17)
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Computer Simulations (7/8)
 The Proposed Scheme
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Computer Simulations (8/8)
表3.3 : Performance Comparison of The Proposed and Conventional Schemes
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Conclusions (1/1)
 This scheme could locate counterfeit frames and
identify the manner of counterfeiting the data.
 Only decreases the PESQ by 0.11
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