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Thesis Report on image steganography using wavelet transform

Apr 12, 2015

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Thesis Report on image steganography using wavelet transform

EFFICIENT STEGANOGRAPHY USING LSB AND ENCRYPTION TECHNIQUEA B.tech Project Report submitted in partial fulfillment of the requirement for the B.Tech. under Biju Patnaik University of Technology, Rourkela.

Submitted By

SIDHARTHA SANKAR PRADHAN ATMASWAROOPA TRIPATHY

Reg. No #0801314109 Reg No. #0801314098

JULY - 2012 Under the guidance of

Dr. SATYARANJAN PATTANAIK

APEX INSTITUTE OF TECHNOLOGY & MANAGEMENT Pahala, Bhubaneswar, Odisha 752101, India

Efficient Steganography using LSB and encryption technique

SYNOPSISSteganography is the process of hiding one file inside another such that others can neither identify the meaning of the embedded object, nor even recognize its existence. Current trends favor using digital image files as the cover file to hide another digital file that contains the secret message or information. Steganography become more important as more people join the cyberspace revolution. Steganography is the art of concealing information in ways that prevent the detection of hidden messages. The goal of steganography is to avoid drawing suspicion to the existence of a hidden message. This approach of information hiding technique has recently become important in a number of application areas. Digital audio, video, and pictures are increasingly furnished with distinguishing but imperceptible marks, which may contain a hidden copyright notice or serial number or even help to prevent unauthorized copying directly. Military communications system make increasing use of traffic security technique which, rather than merely concealing the content of a message using encryption, seek to conceal its sender, its receiver or its very existence. Similar techniques are used in some mobile phone systems and schemes proposed for digital elections. One of the most common methods of implementation is Least Significant Bit Insertion, in which the least significant bit of every byte is altered to form the bit-string representing the embedded file. Altering the LSB will only cause minor changes in color, and thus is usually not noticeable to the human eye. While this technique works well for 24-bit color image files, steganography has not been as successful when using an jpeg color image file, due to limitations in color variations and the use of a color map. The advantages of LSB are its simplicity to embed the bits of the message directly into the LSB plane of coverimage and many techniques use these methods . Modulating the LSB does not result in a humanperceptible difference because the amplitude of the change is small. Therefore, to the human eye, the resulting stego-image will look identical to the cover-image. This allows high perceptual transparency of LSB. Another level of security adds to steganography by using an encryption technique for encrypting message before adding to image.

i

Efficient Steganography using LSB and encryption technique

AcknowledgementWe would like to express our immense sense of gratitude to our guide, Dr. Satya Ranjan Pattanaik, for his valuable instructions, guidance and support throughout our project.

We again owe our special thanks to Dr. Satya Ranjan Patanaik, B.Tech. project Coordinator for giving us an opportunity to do this report.

And finally thanks to Prof. R.C. Das, Principal, AITM for his continued drive for better quality in everything that happens at AITM. This report is a dedicated contribution towards that greater goal.

SIDHARTHA SANKAR PRADHAN REG. NO.-0801314109

ATMASWAROOPA TRIPATHY REG. NO-0801314098

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Efficient Steganography using LSB and encryption technique

Table of ContentsSynopsis List of Figures List of Tables

Chapter No.

Description

Page No.

1 1.1 1.2 1.3 1.4 1.5

Introduction and Scope of the Thesis Introduction Scientific Background Background of the Problem Objective Scope 1 1 2 3 3

2 2.1 2.2 2.3

Information hiding using Steganography Introduction Overview of Steganography Summary 4 5 10

3

Least Significant Bit insertion

3.1 3.2 3.3 3.4

Introduction Least Significant Bit Insertion Secure Information Hiding System Advantage of LSB Technique

11 11 12 15iii

Efficient Steganography using LSB and encryption technique

3.5 3.6

Disadvantage of LSB Technique Summary

16 16

4 4.1 4.2 4.3 4.4 4.5

Encryption and RSA algorithm Introduction Types of Encryption Asymmetric Encryption Schemes RSA algorithm Summary 17 18 19 22 26

5 5.1 5.2 5.3 5.4

Experimental Process, Results & Discussion Concealing Message Extracting Message Experimental Results Discussion 27 28 29 30

6 6.1 6.2

Conclusion Future thoughts Conclusion 31 31

Bibliography

iv

Efficient Steganography using LSB and encryption technique

List of FiguresFigure No.2.1 3.1 5.1 5.1

DescriptionBasic Steganography model Producing Stego image process Steganography at sender side Output at the Receivers side

Page No.6 13 29 30

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Efficient Steganography using LSB and encryption technique

Chapter - 1Introduction and Scope of the Thesis1.1 General IntroductionOne of the reasons that intruders can be successful is that most of the information they acquire from a system is in a form that they can read and comprehend. Intruders may reveal the information to others, modify it to misrepresent an individual or organization, or use it to launch an attack. One solution to this problem is, through the use of steganography. Steganography is a technique of hiding information in digital media. In contrast to cryptography, it is not to keep others from knowing the hidden information but it is to keep others from thinking that the information even exist

1.2 Scientific BackgroundSteganography is an ancient technology that has applications even in todays modern society. A Greek word meaning covered writing, steganography has taken many forms since its origin i n ancient Greece. During the war between Sparta and Xerxes, Dermeratus wanted to warn Sparta of Xerxes pending invasion. To do this, he scraped the wax off one of the wooden tablets they used to send messages and carved a message on the underlying wood. Covering it with wax again, the tablet appeared to be unused and thereby slipped past the sentries inspection. However, this would not be the last time steganography would be used in times of war. In World War II, the Germans utilized this technology. Unlike the Greeks, these messages were not physically hidden; rather they used a method termed null ciphering. Null ciphering is a process of encoding a message in plain sight. For example, the second letter of each word in an innocent message could be extracted to reveal a hidden message. Although its roots lay in ancient Greece, steganography has continually been used with great success throughout history. Today1

Efficient Steganography using LSB and encryption technique

steganography is being incorporated into digital technology. The techniques have been used to create the watermarks that are in our nations currency, as well as encode music information in the ever-popular mp3 music file. Copyrights can be included in files, and fingerprints can be used to identify the people who break copyright agreements. However, this technology is not always used for good intentions; terrorists and criminals can also use it to convey information. According to various officials and experts, terrorist groups are hiding maps and photographs of terrorist targets and posting instructions for terrorist activities on sports chat rooms, and other Web sites. This aspect of steganography is what sparked the research into this vast field and Education and understanding are the first steps toward security. Thus, it is important to study steganography in order to allow innocent messages to be placed in digital media as well as intercept abuse of this Technology.

1.3 Background of the ProblemSteganography [1] become more important as more people join the cyberspace revolution. Steganography is the art of concealing information in ways that prevent the detection of hidden messages. Steganography include an array of secret communication methods that hide the message from being seen or discovered.

The goal of steganography is to avoid drawing suspicion to the existence of a hidden message. This approach of information hiding technique has recently become important in a number of application areas. Digital audio, video, and pictures are increasingly furnished with distinguishing but imperceptible marks, which may contain a hiding copyright notice or serial number or even help to prevent unauthorized copying directly.

Military communications system make increasing use of traffic security technique which, rather than merely concealing the content of a message using encryption, seek

to conceal its sender, its receiver or its very existence. Similar techniques are used in some mobile phone systems and schemes proposed for digital elections. Some of the techniques used in steganography are domain tools or simple system such as least significant bit (LSB) insertion2

Efficient Steganography using LSB and encryption technique

and noise manipulation, and transform domain that involve manipulation algorithms and image transformation such as discrete cosine transformation and wavelet transformation. However there are technique that share the characteristic of both of the image and domain tools such as patchwork, pattern block encoding, spread spectrum methods and masking.

1.4 ObjectiveThis project comprehends the following objectives:

(i) To produce security tool based on steganographic techniques. (ii) To explore techniques of hiding data using steg