SECURE SPREAD SPECTRUM
WATERMARKING FOR MULTIMEDIA

PRESENTERS :
Mahhek Tahir ,Khizra Samad
, Asma Shaheen
Authors :

Ingemar J.Cox – Senior Member IEEE
Joe Kilian – Member IEEE
F.Thomson Leighton – Member IEEE
Talal Shamoon – Me...
INTRODUCTION
This paper presents a secure algorithm for
watermarking images, and a methodology for digital
watermarking th...
SPREAD SPECTRUM WATERMARK
The problem: how to insert watermark into
most perceptually significant region of
spectrum in a ...
SECURE SPREAD SPECTRUM WATERMARKS
FOR MULTIMEDIA
 Spread spectrum watermark based on DCT
 In order for a watermark to be...
Image and Watermarked Image
METHODOLOGY
Embedding
 Detection and Comparison

EMBEDDING
YCrCb

Reshape back

Y

Descending order of DCT
values

DC
T

Convert to vector
EXTRACTION
YCrCb

Y

DC
T

Convert to vector

Descending order of DCT values

X=
COMPARISON
Watermark detected

Watermark not detected
EXPERIMENTS

Uniqueness of Watermark
Scaling
Crop
Print Xerox and Scan
Collision Attack
IMPLEMENTED EXPERIMENT - SCALING
Half size

Double size
IMPLEMENTED EXPERIMENT - COPPING
Secure Spread Spectrum
Secure Spread Spectrum
Secure Spread Spectrum
Upcoming SlideShare
Loading in …5
×

Secure Spread Spectrum

884 views
768 views

Published on

Published in: Technology, Business
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
884
On SlideShare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
22
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Secure Spread Spectrum

  1. 1. SECURE SPREAD SPECTRUM WATERMARKING FOR MULTIMEDIA PRESENTERS : Mahhek Tahir ,Khizra Samad , Asma Shaheen
  2. 2. Authors : Ingemar J.Cox – Senior Member IEEE Joe Kilian – Member IEEE F.Thomson Leighton – Member IEEE Talal Shamoon – Member IEEE IEEE TRANSATIONS ON IMAGE PROCESSING , VOL 6 - DECEMBER 1997
  3. 3. INTRODUCTION This paper presents a secure algorithm for watermarking images, and a methodology for digital watermarking that may be generalized to audio, video and multimedia data. A watermark should be constructed as an independent and identically distributed Gussain random vector that is imperceptibly inserted in a spread spectrum like fashion into the perceptually most significant spectral components of data. It argue that insertion of a watermark under this rule makes the watermark robust to signal processing operations and common geometric transformation provided that the original image is available and it can be successfully registered against the transform image.
  4. 4. SPREAD SPECTRUM WATERMARK The problem: how to insert watermark into most perceptually significant region of spectrum in a reliability protective manner.  To solve: this problem, frequency domain of the image or sound at hand is viewed as communication channel, and the mark is viewed as a signal that is transmitted through it 
  5. 5. SECURE SPREAD SPECTRUM WATERMARKS FOR MULTIMEDIA  Spread spectrum watermark based on DCT  In order for a watermark to be robust, it needs to be placed in the most significant part of the image.  The watermark will be composed of random numbers drawn from a Gaussian N(0,1) distribution  Inserting the watermark to the image.  Inverse DCT
  6. 6. Image and Watermarked Image
  7. 7. METHODOLOGY Embedding  Detection and Comparison 
  8. 8. EMBEDDING YCrCb Reshape back Y Descending order of DCT values DC T Convert to vector
  9. 9. EXTRACTION YCrCb Y DC T Convert to vector Descending order of DCT values X=
  10. 10. COMPARISON Watermark detected Watermark not detected
  11. 11. EXPERIMENTS Uniqueness of Watermark Scaling Crop Print Xerox and Scan Collision Attack
  12. 12. IMPLEMENTED EXPERIMENT - SCALING Half size Double size
  13. 13. IMPLEMENTED EXPERIMENT - COPPING

×