Content-Dependent Watermarking Scheme in Compressed Speech With Identifying Manner and Location of Attacks

Oscal T.-C. Chen and Chia-Hsiung Liu

Date ： 2009/12/01Speaker ： Jhang Hon-Bin

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۞ Introduction

۞ Proposed Scheme

۞ Computer Simulations

۞ Conclusions

Outline

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Oscal T.-C. Chen

Chia-Hsiung Liu

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

國立中正大學電機工程研究所博士

Received May 31, 2006Revised January 15, 2007This work was supported in part by the National Science Council(NSC), Taiwan, R.O.C.

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Hacker

無 浮水印加入 浮水印

發現攻擊 !!

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Introduction (1/5)

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Introduction (2/5)

Watermarking Scheme

• Robust 、 Fragile 、 Semi-Fragile

Theoretical Foundation of Conventional Watermarks

固定值 : Image ID

變異值 : block index

目前區塊 : Image feature

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Introduction (3/5)

Theoretical Foundation of Conventional Watermarks(Cont.)

鄰近區塊 : Image feature

鄰近區塊 : Image Watermark

識別標誌訊息

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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 value using the following equation:

限制 的範圍

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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。

Proposed Scheme (2/8)

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Design Concept (Solve)(Count.)

• The two schemes can be integrated into one scheme to help achieve our goal.

• Determine attack type and localize attacked segments.

Frame Frame Frame Frame Frame Frame‧ ‧ ‧ ‧ ‧ ‧ ‧ ‧ ‧

Group Group Group

Then (8) is used to generate watermarks.

In most circumstances, (9) is employed to generate watermarks.

Proposed Scheme (3/8)

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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

Proposed Scheme (4/8)

Group g-1 Group g Last group

‧ ‧ ‧‧ ‧ ‧ ‧ ‧ ‧‧ ‧ ‧1 21 1

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Watermark Generation (Count.)

• The first frame in a group

前一個 group 的最後一個frame

目前 frame 的 LSF

下一個 frame 的pitch

由 所產生 是表示 group index 的位元數

Group g-1 Group g Last group

‧ ‧ ‧‧ ‧ ‧ ‧ ‧ ‧‧ ‧ ‧

Proposed Scheme (5/8)

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Watermark Generation (Count.)

• The last frame of all speech data

是最後一個 group 的 frame數 是表示 pitch feature 的位元數

目前 frame 的LSF

前一個frame

Group g-1 Group g Last group

‧ ‧ ‧‧ ‧ ‧ ‧ ‧ ‧‧ ‧ ‧

Proposed Scheme (6/8)

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Watermark Generation (Count.)

• The other frame in a group

目前 frame 的 LSF前一個frame

下一個 frame 的pitch

Group g-1 Group g Last group

‧ ‧ ‧‧ ‧ ‧ ‧ ‧ ‧‧ ‧ ‧

Proposed Scheme (7/8)

產生浮水印 & 嵌入浮水印

取出浮水印

Comparator

原浮水印

取出的浮水印

CorrectOr

Incorrect1 2 31 frame = 240

60 60 60 60

MP-MLQ (6.3 k bit/s)

ITUT G.723.1

Proposed Scheme (8/8)

04 / 23 / 2009 P 16

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Evaluation of Speech Quality

• Eleven conversations of 60.6 ~125.6 s are encoded.

正常語音壓縮 加入浮水印PESQ 3.52 3.41

表 3.1 : 正常語音壓縮和加入浮水印後 PESQ 數值

Computer Simulations (1/8)

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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

Computer Simulations (2/8)

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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 19

表 3.2 : 三種浮水印攻擊對原 2019 frames 語音的影響

Computer Simulations (3/8)

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The Watermarking Scheme Based on (15)

Computer Simulations (4/8)

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The Watermarking Scheme Based on (16)

Computer Simulations (5/8)

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The Watermarking Scheme Based on (17)

Computer Simulations (6/8)

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The Proposed Scheme

Computer Simulations (7/8)

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表 3.3 : Performance Comparison of The Proposed and Conventional Schemes

Computer Simulations (8/8)

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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