I.J. Image, Graphics and Signal Processing, 2015, 6, 10-18 Published Online May 2015 in MECS (http://www.mecs-press.org/) DOI: 10.5815/ijigsp.2015.06.02 Copyright © 2015 MECS I.J. Image, Graphics and Signal Processing, 2015, 6, 10-18 A Comprehensive Image Steganography Tool using LSB Scheme Sahar A. El_Rahman Electrical Department, Faculty of Engineering-Shoubra, Benha University, Cairo, Egypt Email: sahr_ar@yahoo.com Abstract—As a consequence of the fact, transmitting data has been fast and easy these days due to the development of the Internet. Where internet is the most important medium for confidential and non-confidential communications. Security is the major matter for these communications and steganography is the art of hiding and transmitting secret messages through carriers without being exposed. This paper presents a secured model for communication using image steganography. The main concern is to create a Java-based tool called IMStego that hides information in images using Least Significant Bit (LSB) algorithm (1-LSB) and modified Least Significant one Bit algorithm, i.e. Least Significant 2 Bits algorithm (2-LSB). IMStego is a more comprehensive security utility where it provides user-friendly functionality with interactive graphical user interface and integrated navigation capabilities. It provides the user with two operations, which are hiding secret data into images and extracting hidden data from images using 1-LSB or 2- LSB algorithm. IMStego tool hides secrete information in color static images with formats BMP and PNG. Index Terms—Cryptography, Data Hiding, Image Steganography, Information Security, Least Significant Bit I. INTRODUCTION The growth of Internet users has raised the possibility of their data lost or modified by a third party. One of the solutions for protecting data from any potential risk is steganography. Users over the Internet nowadays are struggling with keeping their data secured against any attack done by unauthorized people during transmission. Therefore, messages that meant to be revealed only by the intended receiver could be exposed. To protect users’ data from being manipulated, steganography is used to hide their data in different types of multimedia. Since images are the most widely used medium today and human visual perception of colors is limited. Steganography is a protection method driven from Greek words that means “secret writing”. This method is used to hide secret information within other unsuspicious ones in such a way that it is impossible to detect its existence. On the other hand, cryptography is concerned about hiding the meaning of the message rather than its existence by using a process called “encryption” [1]. Table. 1 shows a comparison between steganography and cryptography. Table 1. Steganography vs. Cryptography. Steganography Cryptography Definition Hiding the existence of the message Hiding the meaning of the message Carrier Any digital media Usually text based Key Optional Necessary Objective Secrete communication Data protection Visibility Never Always Fails when Detected De-ciphered Security is the major matter for the communications over of the internet and steganography is most widely recognized tool for information security [2]. Steganography is the process of hiding information in such a way that prevents the detection of hidden messages. In this technique, no one apart from the sender and the intended recipient even realize that there is a hidden message [3]. it hides a secret message within cover medium such as image, video, text, audio [4]. There are two major types of steganography throughout history, technical and linguistic. Technical steganography is more based upon scientific methods of hiding information while linguistic employs more creative and non-apparent methods [5]. Steganography systems can be grouped by the type of covers used (graphics, sound, text, executable) or by the techniques used to modify the covers [4][6][7]. In image steganography, the cover media is the cover image and the stegomedia is the stegoimage. The images can be manipulated in either spatial domain or frequency domain and accordingly there are two main classes into which the steganography techniques may be divided [8]. There are two directions of steganography (as shown in Fig. 1) protection against detection and protection against removal. The first direction aims to prevent the message from being detected by any unauthorized third party. The second direction is called “document marking” which consist of two branches: “watermarking” that hides trademarks into images, music and other types of multimedia and “fingerprinting” which are hidden serial numbers that enable the owner of an intellectual property to know the costumer who has broken his license agreement [9].