Presentation on developing an android application on digital watermarking.It involves encryption and decryption of text in text file and an image. Different diagrams are also mentioned in it. Further description is given in the ppt.

1. Andromark
Submitted By: Shalabh Mittal (10103435)
CSE Department

2. Overall description of the project
• In this project we are going to propose a framework for embed text string into digital color images and the
text that is embedded is perceptually invisible to Human Visual System (HVS). Many text steganographic
systems are available that are passing the text with digital media as a form of message digest that can be
hacked easily. Here our algorithm supersedes the conventional algorithms. Instead of forming message
digest first a 32-bit secret key will be provided by the encrypter and that will be applied on the text with a
hash function. That gives us a pseudo byte stream. Now we embed that pseudo byte stream directly to
image pixels and after that the text will become the physical property of the encrypted image. On the other
end if an intruder tries to perform the extraction of the text with a wrong secret key, he will not be
succeeded. In the proposed framework the Information of Red (R), Green (G) & Blue (B) values of the
pixels of the host color image are retrieved. Subsequently the text is converted into byte stream with respect
to the ASCII values of the characters present in the text. Triggering that byte stream with the secret key and
hash function produces the pseudo byte stream. Each bit of this byte stream will be embedded in to the
LSBs of RGB bytes of the image pixels that ensure the invisibility of text in the encrypted image. The
extraction of the text is blind i.e., except the secret key nothing is needed for text decryption.

3. Digital Watermarking
• A digital watermark is a kind of marker covertly embedded in a noise-tolerant signal such as audio or
image data. It is typically used to identify ownership of the copyright of such signal. "Watermarking"
is the process of hiding digital information in a carrier signal; the hidden information should,[1] but
does not need to contain a relation to the carrier signal. Digital watermarks may be used to verify the
authenticity or integrity of the carrier signal or to show the identity of its owners. It is prominently
used for tracing copyright infringements and for banknote authentication. Like
traditional watermarks, digital watermarks are only perceptible under certain conditions, i.e. after
using some algorithm, and imperceptible anytime else.[2] If a digital watermark distorts the carrier
signal in a way that it becomes perceivable, it is of no use.[2] Traditional Watermarks may be applied
to visible media (like images or video), whereas in digital watermarking, the signal may be audio,
pictures, video, texts or 3D models. A signal may carry several different watermarks at the same time.
Unlike metadata that is added to the carrier signal, a digital watermark does not change the size of
the carrier signal.
•

4. Problem Statement
• The former consists of linguistic or language forms of hidden writing. The later, such as invisible ink, try of
hide messages physically. One disadvantage of linguistic steganography is that users must equip themselves
to have a good knowledge of linguistry. In recent years, everything is trending toward digitization. And with
the development of the internet technology, digital media can be transmitted conveniently over the network.
Therefore, messages can be secretly carried by digital media by using the watermarking techniques, and
then be transmitted through the internet rapidly.
• Watermarking is the art of hiding the fact that communication is taking place, by hiding information in
other information. Many different carrier file formats can be used, but digital images are the most popular
because of their frequency on the internet. For hiding secret information in images, there exists a large
variety of steganography techniques some are more complex than others and all of them have respective
strong and weak points.
• So we prepare this application, to make the information hiding more simple and user friendly.

5. LOGIN PAGE/REGISTER PAGE

6. • As the user Run the app, the 1st page that
opens up is Login and Registration Page.
• New User will first register himself/herself by
clicking on the Sign Up Button.
• Enters his/her Mobile No., name, email
address and password

7. AFTER REGISTERING
• After Login, A new window opens, now user has the choice of
watermarking the text by voice or by typing the encrypted text.
• If the user selects Text, a new window opens and ask the user
to browse the location of the image.
• Now he/she enters the text in the next line.
• Now the user presses the Encrypt Button and the Encryption
algorithm start running.

8. LIST VIEW
• Encrypted image gets displayed and automatically it
get stored in the Sd Card of the mobile device.

9. For Decreypting Image
• Now the receiver who wants to decrypt the image, open
the decryption application.
• Select the encrypted image from the gallery where
image is stored in an encrypted folder.
• Click on the decrypt button.
• Original image and secret message is displayed to the
receiver.

12. Algorithm for Embedding Text using
LSB Scheme:
Let the color host image be 'HI'. A text string'S' will be embedded in it to form
the encrypted image (EI) and again will be extracted from it with the
implemented application software. In following discussion, we propose the
algorithm for embedding text into the color host image.
[INSERT_TEXT]
• Input: Color host image (HI), Text String (S), Secret key (K).
• Output: Text encrypted image (EI).

13. Stepl: H[= getyixel_info (HI)
Step2: LI = LSB_to_zero (HI)
Step3: Ar = ASCII_chopper (S)
Step4: HASH = Hashjunc (K, LI)
Step5: Pr = Pseudo_generator (Ar, HASH)
Step6: EI= replace (LI , Pr )

14. • Function Definitions:
• Get_pixel_info(): This function will bring the binary information of R, G, B values of the
pixels of host image (HI) that forms HI.
• LSB to zero(): This function will convert the LSB of the binary values of Hj to zero to form
Lj.
• ASCII_chopper(): This function will grab the ASCII values of the characters present in the
text string (S) to form byte strem (Ar).
• Hash_func(): This function will generate a byte stream with the help of a secret key (K) and
LI to form HASH.
• Pseudo...J5enerator(): This function will perform XOR operation between Ar and HASH to
form Pr.
• Replace(): This function will replace the LSBs of L] with the individual bits of Pr that forms
encrypted image (EI).

16. Algorithm for Extracting Text using
LSB Scheme:
• [EXTRACT_TEXT]
• • Input: Text encrypted image (EI), Secret key (K).
• • Output: Extracting Text (S}J.
• Stepl: Pn = retrieve (EI)
• Step2: L" = LSB_to_zero (EI)
• Step3: HASH = Hash _ func (K, Lu)
• Step4: AT,= ASCII_generator (HASH, Pn)
• Step5: Sl= Text_generator (An)

17. • • Function Definition:
• Retrieve(): This function will retrieve LSB of blue value of each pixel of
encrypted image (EI) that forms PT, i.e., the pseudo byte stream.
• ASCII_generator() : This function will perform XOR operation between Pn
and HASH to form An. This function performs just reverse operation of
Pseudo_generator ()
• Text_generator() : This function will convert the ASCII byte stream AT' to
text string S,. Other functions are already defined during embedding text.

19. Use-Case Diagram

20. Block Diagram

21. Sequence Diagram

22. RISK ANALYSES
S. No. Risk Area # of Risk
Statement
Weights Total Weight Priority
1 Performance 6 9+9+1+9+1+3 32 1
2 Project Scope 5 9+9+1+3+6 28 2
3 Hardware 2 6+9 15 4
4 External
Inputs
3 3+1+1 5 5
5 Testing
Environment
2 3+1 4 6
6 Personal
Related
2 9+9 18 3
Testing Environment
Personal Related
Hardware
Project Scope
External Inputs
9
6
3
9
9
1
1
1
3
9
PERFORMANCE

23. CONCLUSION
• 5.1 Findings:
• Android development is primarily done in Java, which is great because it is already an established, stable
language with a large community around it in addition to the Android community itself. We were interested
in getting started with Android development, so some key resources that helped us to get off the ground,
depending on our experience with development and Java. Because there are so many disparate resources for
learning Java and the Android environment, we wanted to pull together the crucial resources to learning the
platform and running your first application.
• We were familiar with Java programming or object-oriented development concepts, so it helped us to learn
the Android platform easily. Google’s own Android Developer’s Guide assumes significant knowledge of
programming concepts, conventions, and tools. While we don’t need to be an expert, if we were not
comfortable with a command line or don’t already have Eclipse installed, their guide will not start you in a
position to be successful. There are other great getting-started guides available from good resources, but
they also expect at least some background Java knowledge before you can be productive with the tutorial
and do more than just follow provided steps.

24. • As we were learning the android development for the first time so
thenewboston.org tutorials for android development were really helpful.
• Once we figured out the essentials of Java development and were comfortable with
the concepts we started our development in ADT. The resources took us from
installing the Android SDK and Eclipse, the preferred Android development
environment, through creating a sample application and running it either in a virtual
machine on our computer or on an Android device. There is a fairly steep learning
curve here, but once we run through this exercise we had the practical skills to
begin real development.

25. Future Work
• Security of secret message could be increase more by using matlab
specific algorithms.
• Image-Image encryption and decryption of same could be done.
• Features like voice recognization, text to speech, taking image
instantly through camera could be implemented.
• Key used for encryption could be generated using modern
techniques.

26. THANK YOU