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Image Integrity and Correction Image Integrity and Correction Using Parities of Error Control Using Parities of Error Control CodingCoding

By Jaejin Lee and Chee Sun Won

Presented by Du-Xiao Cai

S9056031@cs.nchu.edu.tw

IEEE International Conference on Multimedia and Expo (III) 2000

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OutlineOutline

Introduction

Watermark Encoding

Authentication and Correction

ECC for the Watermark Sequence

Experimental Results

Conclusions

Comments

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IntroductionIntroduction

Adopt ECC technique to generate the watermark.

The scrambling key 1. Increase the correction capability.

2. Used as a key for the authentication.

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Watermark EncodingWatermark Encoding

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Authentication and CorrectionAuthentication and Correction

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ECC for the Watermark ECC for the Watermark SequenceSequence

Reed-Solomon(RS)1. A Reed-Solomon code is specified as RS(n,k)

with s-bit symbols. n = 2s – 1

2. Can correct up to t symbols ,2t=n-k N=28-1=255T=11K=255-22(2t)=233

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ECC for the Watermark SequenceECC for the Watermark Sequence

21122121

4ppkpkp

kk

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Experimental ResultsExperimental Results

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ConclusionsConclusions

Watermarking sequence can be used for correction of illegal modifications.

RS technique.

Scrambling key used for authentication and increase the correction capability indirectly.

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CommentsComments

1. Invisible but not undeletable.

2. Not resistant to lossy data compression.

3. Important information require more RS parity bytes,but not.