Presented by:- MANJESH KUMAR (12100027) Guided by:-
Dr. David Peter S.
CONTENTS • • • • • •
• • • •
Introduction Need for video watermarking watermarking Video watermarking terminologies Types for video watermarking Desired properties Application of watermarking watermarking Structure of a Typical Video Watermarking System
An algorithm of video watermarking Attack on watermark Conclusion References
INTRODUCTION Definition: A digital watermark is a digital signal or pattern inserted into a digital document such as text, graphics or multimedia, and carries information unique to the copyright owner.
Video watermarking is an extension of this concept.
Need for video watermarking
Protect copyright of a data. Video Watermarking can help ◦ Prove ownership ◦ Identify a misappropriating person ◦ Trace the video dissemination Broadcast Broadcast Monitoring Video watermarking introduces some issues not present in image watermarking watermarking Frame averaging, frame dropping, frame swapping …
Video watermarking terminologies •
Digital Video
•
Payload
•
Perceptibility
•
Robustness
•
Security
TYPES of Video Watermarking
Two types :1. Visible 2. Invisible
Visible watermarks it’s use : 1. To discourage unauthorized usage. 2. As an advertisement
Visible watermarking algorithm Least Significant Beat (LSB)
EXAMPLE OF VISIBLE VIDEO WATERMARKING
Invisible watermarks Three types of Invisible watermark : 1. 2. 3.
Robust Watermarks Fragile Watermarks Public and Private Watermark No degradation in the aesthetic quality of the data. Invisible Robust Video Watermarking Techniques
Spatial Domain Method Frequency Domain Method
DESIRED PROPERTIES
Robust Video watermarking ( frame averaging, frame dropping, frame swapping... )
Recoverable from a document Removable by authorized users Low error probability Provide the original information embedded reliably Capacity Invisible
APPLICATION OF WATERMARKING •
Owner Identification Identification
•
Proof of Ownership
•
Transaction ransac tion Tracking racking
•
Content Authentication
•
Broadcast Monitoring
•
Device Control
•
Automatic monitoring of copyrighted material on the Web
A Generic approach to watermarking digital data
There are 3 main processes involved in watermarking — 1. Insertion of a watermark 2. Detection of a watermark 3. Removal Removal of a watermark
Inserting a watermark
It consists of :A watermark insertion unit that uses:a. Original video b. Watermark c. A user key to obtain the watermarked video.
watermark insertion unit The user key , input video and the watermark are passed through a watermark insertion unit.
This results in a watermarked video.
Watermark Extraction Unit Two phases:
1. Locating the watermark 2. Recovering the watermark information.
Watermark Detection Unit
Consists of :a. An extraction unit to first extract the watermark. b. Compare it with the original watermark inserted. c. The output is Yes or No depending on whether the watermark is present.
A watermarking algorithm — The LSB technique Let’s consider still images.
Each pixel of the color image has three components — red, green and blue. 3 bytes for each pixel. Each color has 1 byte, or 8 bits. bi ts. Each bits has it’s own value 2pow(n) .
The LSB technique…….
A pixel that is bright purple in color can be shown as
X0 = {R=255, G=0, B=255}
Another pixel:
X1 = {R=255, G=0, B=254}
The Algorithm 1.A raw bitmap image „A’ will be selected from the set of standard test images. Let this be the base image on which the watermark will be added. 2. A raw bitmap image „B‟ will be selected from the set of standard test images. This will be the watermark image which will be added to the base image. 3. The most significant bit henceforth will be mentioned as MSB, of watermark image „B‟ will be read and these will be written on the least significant bit, henceforth will „A‟. be mentioned as LSB, of base image „A‟ 4. Thus, „A’ will be watermarked with ‘B’ resulting in a combined image ‘C‟. 5.
‘C’
therefore will now contain an image
‘A’ ‘A’
which has its LSBs replaced with
the MSBs of ‘B‟.
6. This technique is used to add an invisible and visible watermark.
Distortions and attacks
Additive Noise.
Cropping.
Compression.
Statistical Averaging.
Multiple Watermarking.
Mosaic Attack
An Algorithm of Invisible Video Watermarking
Raw video watermarking ◦ DWT (Discrete wavelet transform) ◦ DCT ( Discrete cosine transform) ◦ DFT ( Discrete frequency transform)
Discrete Wavelet Transform Normalized to 256 X 256 pixel size
Perform DWT for each frame
Advantage of DWT
Prevent from frame dropping Prevent from adding noise / another video
Mark with m1
Mark with m3
Mark with m0
Scene change occur
Mark with m6
Watermark Preprocess
Safe from frame averaging Hard to reconstruct the watermark Place the bitplanes side by side
85 64 Crop
0 1 2 3
4 5 6 7
Bit Decomposition
m0
8 bitplanes
0 25 1 6 2 3
m7
8 bitplanes
0 25 1 6 2 3
17 0
17 0
4 5 6 7
4 5 6 7
Total 8 images is obtained
Watermark Embedding
C[i] = C[i] + 1 , if W[j] = 1 C[i] = C[i] , otherwise LL, HH is not watermark LL HL LH HH
170
HL3
LH3 HH3 LH2
HL2 HL1 HH2
0
4
256 1
5
2
6
3
7
Watermark mi LH1
HH1
Watermark Detection Mark with m1
Mark with m3
Mark with m0
Mark with m6
Scene change occur
1. Video Frame 256 X 256
3. DWT
2. Detect the scene change
4. Compare
Original video frames
DWT result frames 5. Averaging the watermark get from different frames
170 85 64
256
6. Combine 8 bit-planes
Watermark m Watermark mi
m0 m1 m2 m3
170
m4 m5 m6 m7
256 7. Get different part of W from different scene and reconstruct the large image
0 1 2 3
4 5 6 7 Extracted
8. Correlate and verify
E
Original
O
Future Direction
Implement and use do experiment on the scheme
Identifiable from very short segment of video
Change to blind watermarking scheme
ATTACK ON WATERMARK
Compression Rescaling Cropping Multiple watermarks
• • • •
Frame averaging Frame dropping Frame swapping Statistical analysis
CONCLUSION
Need due to Copyright protection Different Different from image watermarking Brief review of current technologies DWT-based Video Watermarking Scheme with Scramble Watermark Future Direction Inadequate for general use Different tools offering this watermarking Set to grow
REFERENCES
F. Hartung and M. Kutter, “Multimedia watermarking techniques”,Proceedings of the IEEE, vol. 87, no. 7 , July1999.
I. Cox, J. Kilian, T. Leighton, and T. Shamoon, “Secure spread spectrum watermarking for images, audio and video,” in Proc. IEEE Int. Conf. Image Processing (ICIP 96), Lausanne, Switzerland, Sept. 1996.
Yeo and M.M. Yeung, “Analysis and synthesis for new digital video applications,” icip, International Conference on Image Processing (ICIP'97),vol. 1, pp.1,1997.
Ingemar J. Cox, Matthew L. Miller, Jeffrey A. Bloom “Digital Watermarking” Morgan Kaufmann Publishers ISBN: 1-55860-714-5 1-55860-714-5
http://www-ee.uta.edu/dip/Courses/ http://www-ee.uta.edu/ dip/Courses/EE5355/jpeg.ht EE5355/jpeg.html ml
“Privacy principles for digital watermarking”, Ver. 1.0, May 2008. Website: https://www.cdt.org/
