SECURE REVERSIBLE VISIBLE IMAGE WATERMARKING WITH AUTHENTICATION Source

: Signal Processing: Image Communication 25(2010) pp.10-17

Authors

: Han-Min Tsai, Long-Wen Chang

Presenter

: Huynh Ngoc Tu

Date

: June 9 th , 2010 1

OUTLINE

• INTRODUCTION • PROPOSED SCHEME • EXPERIMENTAL RESULTS • CONCLUSIONS

INTRODUCTION

There are two kinds of reversible watermarking: -Lossless invisible watermarking -Lossless visible watermarking Three major requirements for visible watermarked images: -Visibility -Transparency -Robustness

THE PROPOSED SCHEME (1/6) Visible watermarking Protection and Transparency adjustment Reversible data embedding

THE PROPOSED SCHEME (2/6) Alpha component value defining its opacity: α=0: completely transparent α=1: totally opaque 5

THE PROPOSED SCHEME (3/6) VISIBLE WATERMARKING W: watermark image R: region of host image R w : watermarked image m : mean value of pixel values Host image Watermark image 6

THE PROPOSED SCHEME (4/6) 14 26 23 25 12 13 21 15 17 30 32 10 50 16 18 Host image 20

1 0 0 1

Watermark image 14 26 23 25 12 17 15 10 50 16 18 20 Watermarked image 7

THE PROPOSED SCHEME (5/6) 14 26 23 25 12 13 111 15 17 116 32 10 50 16 18 20

D

corresponding to

W

(

x,y

) = 1 is equal 0

D

corresponding to

W

(

x,y

) = 0 is equal 1:

LSB

of

R

8

THE PROPOSED SCHEME (6/6) Protection and transparency adjustment of the watermarked region

S

= {s 1 , s 2 ,…, s

n

}: random sequence

X

1

: subsequence of n

1

intergers X n

1 2

: subsequence of n = 3n

2 2

intergers n = n

1

+ n

2

, S

=

X

1 +

X

2

n

: number of black pixels in

W p i

: pixel in

R w

in

W

corresponding to black pixel Distortion: 9

EXPERIMENTAL RESULTS(1/5)

Watermark image Watermarked image 10

EXPERIMENTAL RESULTS(2/5)

The watermarked images produced by the proposed method with (a) F-16 (b) Lena (c) Baboon. 11

EXPERIMENTAL RESULTS(3/5)

(a)-(c): zoom-in watermarked images “Lena” with different sequences (d)-(f): recovered images from images (a)-(c) 12

EXPERIMENTAL RESULTS(4/5)

Visual effects on the cropped watermarked images‘‘Lena’’,‘‘F-16’’,and‘‘Baboon.’’ (a)–(c)Yongjian and Byeungwoo method [5]. (d)–(f)The proposed method 13

EXPERIMENTAL RESULTS(5/5)

Comparison among scheme [5], scheme [7] and proposed scheme [5] H. Yongjian, J. Byeungwoo, Reversible visible watermarking and lossless recovery of original images, IEEE Transactions on Circuits and Systems for Video Technology 16 (2006) 1423–1429.

[7] Y. Shu-Kei, O.C. Au, H. Chi-Wang, W. Hoi-Ming, Lossless visible watermarking, IEEE International Conference on Multimedia and Expo (2006) 853–856. 14

CONCLUSIONS

Features: • Lossless image recovery • Unlimited watermark size • Authenticating ability Demerit: require side information 15