1.1 Introduction
Security of confidential data is the prime issue in today’s digital world. Steganography is one of the solutions to provide security, basically it is an art of hiding confidential data inside another image called cover image (Prabakaran et al., 2013). Normal user cannot see to the confidential data directly, once it is hidden in cover image. Hidden data is invisible to unauthorized user and only authorize user can see confidential data by using proper process of steganography method. Beside steganography another security technique is also available called cryptography (Akhtar et al., 2013). Cryptography convert secrete data into unreadable form, generally it is called encryption and through decryption unreadable form convert into readable form. Normally only one security approach is used at a time by the users either cryptography or steganography (Kumar, 2013).
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
In the present world of communication, one of the necessary requirements to prevent data theft is securing the information. Security has become a critical feature for thriving networks and in military alike. Cryptography and Steganography are well known and widely used techniques that manipulate information (messages) in order to cipher or hide their existence. These techniques have many applications in computer science and other related fields: they are used to protect military messages, E-mails, credit card information, corporate data, personal files, etc. This protection is done or carried out by first generally encrypting the data, then hiding it so as to only be discovered for whom it is meant or intended for. Before the modern era, cryptography was concerned solely with message confidentiality (.i.e., encryption — conversion of messages from a comprehensible form into an incomprehensible one, and back again at the other end), rendering it unreadable by interceptors or eavesdroppers without the secret knowledge which is the key needed for decrypting the message. In recent decades, the field has expanded beyond confidentiality concerns to include techniques for message integrity checking, sender/receiver identity authentication, digital signatures, interactive proofs, and secure computation, amongst others. Encryption attempts to ensure secrecy in communications, such as those of spies, military leaders, diplomats etc.
Steganography (— hiding the existence of a message so as to keep it confidential) was also first developed in ancient times. An early example, from Herodotus (- a Greek historian), concealed a message – a tattoo on a slave’s shaved head – under the regrown hair. In modern terms, Steganography is usually implemented computationally, where cover works such as text files, images, audio files, and video files are altered in such a way that a secret message can be embedded within them. Although Steganography techniques are very similar to that of digital watermarking, one big distinction must be highlighted between the two. In digital watermarking, the focus is on ensuring that nobody can remove or alter the content of the watermarked data, even though it might be plainly obvious that it exists. Steganography on the other hand, focuses on making it extremely difficult to tell that a secret message exists at all. If an unauthorized third party is able to say with high confidence that a file contains a secret message, then steganography has failed.
1.3 Statement of Problems
The problem is security. The password method used in almost all commercial operating systems is probably not very strong against a sophisticated or unsophisticated attacker. The choice of data encryption comes next in the minds of those that want reduction of unauthorized access on confidential files or data. Security provided by the computer operating systems come with a preset super user account and password.
The super user may have a password to control network functionality, another to conduct or access nightly backups, create accounts, and so on. For a cracker, logging on to a system as the super user is possibly the best way to collect data or do damage. If the super user has not changed an operating system’s preprogrammed passwords, the network is vulnerable to attack. Most crackers know these passwords, and their first attempt to break into a network is simply to try them. If an attacker cannot log on as the super user, the next best thing might be to figure out the user name and password of a regular user.
1.4 Aim and objective of the Study
The aim of the study is to Design and Implement a Digital Image Cryto System with Adaptive Steganography. In achieving this aim, the following specific objectives of study were considered to design and develop a system that will;
- Improve the Digital Image Cryto System through Adaptive Steganography.
- Provide a means of safeguarding image data in a system
- Enhance the integrity of data
- Facilitate the use of more sophisticated tool against hacking, cracking, bugging of a system.
1.5 Significance of Study
Image Data security in these contemporary times is a must. For your secrets to be secure, it may be necessary to add protections not provided by your computer operating systems. The built-in protections may be adequate in some cases. If no one ever tries to break into or steal data from a particular computer, its data will be safe. Or if the intruder has not learned how to get around the simple default mechanisms, they’re sufficient. But many attackers do have the skills and resources to break various security systems. If you decide to do nothing and hope that no skilled cracker targets your information, you may get lucky, and nothing bad will happen.
One of the most important tools for protecting your data from an authorized access is Data Encryption, any of various methods that are used to turn readable files into gibberish. Even if an attacker obtains the contents of the file, it is gibberish. It does not matter whether or not the operating system protections worked.
1.6 Scope of the Study
The study focuses on the Design and Implementation of Digital Image Cryto System with Adaptive Steganography.
1.7 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Establishment Policies: Establishment policies posed a serious limitation as most staffs are not ready to release information needed for this project work. There were lots of information needed from the staffs of this institution to enhance the study which took them time to release or they did not release at all for security purposes, hence the scope was reduced.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).
1.8 Definition of Terms
- Encryption: A process of converting data/information into another form.
- Decryption: A process of converting data/information (multimedia) back to its Original form.
- Clear-text/plaintext: Original data/information before it is enciphered / scrambled.
- Ciphered text/cryptogram: Information (multimedia) that has been converted into other symbols or form.
- Ciphers: The secret code used to convert plain text message.
- Hackers: People who steal information without permission.
- Cryptography: This is process of hiding writing information.
- Cryptographers: Those that hide writing information.
