1. OBJECTIVE
 To provide authenticity or the identity of ownership
on images.
 Protecting digital images against un-authorized use,
i.e. duplication, mis-representation and mis-
distribution or illegal usage.
 main focus is to embed a color watermark image in
to a color host image.

2. Introduction
 Digital watermarking
 The process of embedding digital information into a
digital signal.
- Purpose
- Various types of Watermarking
- Basic requirements
 Invisible Fragile Image Watermarking.
 Embed a color watermark image in a color Host
Image.

3. Classification

4. Requirements :
 The extracted watermark remains intact. i.e., image
authentication is guaranteed.
 Quality of generated watermarked image should
improved. w.r.t. others.
 The security issues related to the watermark are
provided using a secret key and a hash function.

5. Ideal Properties
 perceptually invisible to prevent obstruction of
original image.
 statistically invisible, so it can’t be detected or
erased.
 extraction should be simple and accurate.
 the watermark should be able to determine the
true ownership of the Image.

6. Features:
 Transparency : Perceptual quality of data
being protected.
 Robustness : with stand against any
intentional transformations.
 Capacity : the ability to detect the watermarks
with a low probability of error.

7. Process:
 Host image is divided in to some blocks.
 Embed watermark at LSB of Blue values of all
such blocks .
 Manipulating only the ‘Blue values’(HVS).
 No. of host image blocks should be equal to the
no. of bit embedded multiplied by the bit size of
RGB.

8. Technique: 2-bit scheme
Fig: Block diagram

9. Process diagram: 2-bit scheme

10. Technique : 1-bit scheme
Fig: Block diagram

11. Process Diagram: 1-bit scheme

12. Algorithm: Embedding
 get_blue pixel_info (Yi)
 onebit_to_zero (Yip)
 hash_for_mesg_digest (Li , K)
 extract_onebit (A)
 compute_XOR (Hi , Ai)
 replace_(Yip , Xi )

13. Execution of Algorithm for Embedding watermark
HOST IMAGE (Y)
WATERMARK IMAGE (A)

14. H WATERMARK (A)
O
S
T
(Y)
R G B
R
G
B

15. get_blue pixel_info (Yi)
B
L
U
E
P
L
A
N
E LSB-0 BLUE BIT PLANE (Ybi )
Dividing into Blocks
8 BIT-PLANES ONEBIT_TO_ZERO (Li)

16. hash_for_mesg_digest (Li , K)
Li
Secret Key (K)
MD5 1111000010101100
Applying
HASH (Li ,K)

17. C
O H
M
P
A
U S
T H
E
X
O XOR
R
R LSB-0 BLUE BIT PLANE B
G

18. replace_(Yip , Xi ) LSB-0 Blue bit-plane
LSB-1
LSB-2
LSB-3 BLUE PLANE
LSB-4
LSB-5
LSB-6
LSB-7

19. WATERMARKED IMAGE
GREEN PLANE
RED PLANE
BLUE PLANE

21. Execution of Algorithm for Extracting watermark
 onebit_to_zero (Wi)
 hash_for_mesg_digest (L’i , K)
 retrieve Wi
 compute_XOR

22. Execution of Algorithm for Extracting watermark
WATERMARKED
R
G
B

23. B
L
U
E
P
L
A
N
E LSB-0 BLUE BIT PLANE (Wdbi )
Dividing into Blocks
8 BIT-PLANES
ONEBIT_TO_ZERO (Li)

24. L’i hash_for_mesg_digest (L’i , K)
Secret Key (K)
MD5 1111000010101100
Applying
HASH (L’i ,K)

25. HASH
XOR
LSB-0 BLUE BIT PLANE (Ri)

26. R G B
Extracted watermark (A’i)

28. Observation : We can easily see that A'i= Ai. So our watermark
image is retained intact (complete) after extraction, by combining
all bit-planes from all blocks.
Advantages:
 Security
 Persistency of Image Quality
 At the time of extraction neither the host image nor the
watermark image is needed.
 Copyright Protection
 Tamper Proof verification

29. CONCLUSION AND FUTURE SCOPE
 Among large variety of watermarking techniques, an attempt has
been made to develop color image watermarking scheme for color
images.
 Both host image and watermark images are color images.
 The extracted watermark remains intact, i.e. image authentication is
guaranteed.
 As a future research scope attempt will be make to develop the
framework to semi-fragile watermarking, to detect malicious
manipulations on an image, while allowing acceptable manipulations.

30. Thank you