ポスター発表会 2006 年 2 月 20 日 1/13 Two Channel Digital Watermarking for Music based on Exponential Time-spread Echo Kernel Nguyen Thi Huong Lien 04M35670 ([email protected])

2006 2 20ポスター発表会 年 月 日 1/13

Two Channel Digital Watermarking for Musicbased on Exponential Time-spread Echo Kernel

Nguyen Thi Huong Lien04M35670 　 ([email protected])

廣田研究室知能システム科学専攻・東京工業大学

楽曲に対する指数型時間拡散エコーカーネルに基づく２チャネル電子透かし法

審査員廣田薫教授 高橋宏教授 山村雅幸教授 室伏俊明助教授 高玉圭樹講師

発表時間：　 14.00~15.30

2006 2 20ポスター発表会 年 月 日 2/14

Digital Watermarking: Motivation & Background

watermark

EmbeddingExtraction/

yes/no

Detection

Digital Watermarking

Easy copy

Copyright Problems Imperceptibility Robustness

Capacity

Digital Watermarking: Trade-off

2006 2 20ポスター発表会 年 月 日 3/14

Digital Watermarking: Attacks

Filter

Ambience

Conversion

Compression

Modulation

Time stretchClipping

t

magnitude

t

magnitude

Type 1: Affect magnitude of samples

Type 2: Affect time sequences(For ex.: clip a portion)

2006 2 20ポスター発表会 年 月 日 4/14

Proposed 2 Channel Digital Watermarking

Embedding Process2channelseparation

Segment-tation

Segment-tation

LSB

EchoHiding

Encoding

Re-segment

Re-segment

2channelunification

originalsignal

watermarkedsignal

watermark

watermarklength

watermarkbits

2006 2 20ポスター発表会 年 月 日 5/14

Least Significant Bit Channel (1/2)

16 bit quantization

watermark bit

watermark bit

1

0th 15th 9th

1 0 1 0 0 1

1 0 1 00 1

0

LSB

LSB (H. Yeh, J. Kuo, 1999): Robust to attacks of type 2

0

1

Original signal

0 t

2006 2 20ポスター発表会 年 月 日 6/14

Least Significant Bit Channel (2/2)

LSB for Proposed 2 Channel DW

watermark

t

magnitude

1 segment = watermark lengthOriginal signal

Embed watermark into each segment

2006 2 20ポスター発表会 年 月 日 7/14

Echo Hiding Channel (1/2)

originalsignal

echo signal

1d

(b) 1 kernel

2( )2

lx

K

originalsignal

echo signal

(c) 0 kernel0d

2( )2

lx

K

2i

EH (D. Gruhl, 1996):Robust to attacks of type 1

=

input output

original signal echo kernel echoed signal

(a) embedding process

original signal

echo

2( )lh

Parameters of echo kernelseffect sound quality

2006 2 20ポスター発表会 年 月 日 8/14

Echo Hiding Channel (2/2)

EH for 2 Channel DW watermark

t

magnitude

1 0 0 1 0

1 kernel 0 kernel 1 kernel0 kernel 0 kernel

Original signal

2006 2 20ポスター発表会 年 月 日 9/14

Exponential Time-spread Echo Kernel (1/2)

Single Echo MethodRoom Reverberation

i

originalsignal

echoesp

1KpK

Exponential time-spreadecho kernel

based on roomreverberation

delay

2006 2 20ポスター発表会 年 月 日 10/14

Original music

Embeddingprocess Watermarked music

Experiment results: 2 Channel DW and ETEK (1/3)

2006 2 20ポスター発表会 年 月 日 11/14

WatermarkExtraction

process

LSB channel EH channel

Can confirm the copyright

Experiment results: 2 Channel DW and ETEK (2/3)

2006 2 20ポスター発表会 年 月 日 12/14

Type of attack Proposedsystem

LSB EH

equalization 72% 45.91% 72%

chorus 71.55% 44.12% 71.55%

cut freq.>15kHz 68.01% 44.43% 68.01%

reverse 62% 55.63% 62%

delay & reverse 57.42% 57.42% 50%

Robustness against attacks

4.57 3.86 5: Imperceptible

　　　 4: perceptible but not annoying

3: slightly annoying 　　　　 　　　　　　　　　

　　　 2: annoying

　　　 1: very annoying

• Average results of sound quality from 7 young people• SONY, MDR-CD900ST Headphone (studio standard)

Experiment results: 2 Channel DW and ETEK (3/3)

Accuracy Rate

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9 10

Music clip

Perc

enta

ge (%

)

従来法提案法

Conventionalmethod

Proposedmethod

Single echo

ETEK

2006 2 20ポスター発表会 年 月 日 13/14

Conclusions

Proposal: 2 channel digital watermarking system based on the LSB

method and EH Exponential Time-spread Echo Kernel for EH

Results: Can confirm copyright information Robustness to various attacks Natural sound quality

2006 2 20ポスター発表会 年 月 日 14/14

Data used in experiments

Song (44.1 kHz, 16 bit) Genre

1. 有難う 1 Pop

2. 有難う 2 Pop

3. 明日は Pop

4. Go back Rock

5. お前の歌 Rock

6. Obata World

7. Path of the wind Ambient

8. Some other time House

9. 絶えない Gospel

10. 椿姫 Classic

List of music and genre used in experiments

Want to listen to the watermarked music?