Steganography is the idea of hiding private or sensitive data or information within

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1 1.1 Introduction Steganography is the idea of hiding private or sensitive data or information within something that appears to be nothing out of the normal. Steganography and cryptology are similar in the way that they both are used to protect important information. The difference between the two is that Steganography involves hiding information so it appears that no information is hidden at all. Nowadays the term Information Hiding relates to both watermarking and steganography. Watermarking is the technique use to hides information in a digital object (video, audio or image) so that information is robust to adjustments or alterations. By watermarking, the mark itself is invisible or unnoticeable for the human vision system. In addition, it should be impossible to remove a watermark without degrading the quality of the data of the digital object. The important application of watermarking is to copyright protection systems, which are intended to prevent unauthorised copying of digital media (pirating). For example if the digital signal (audio, pictures or video) is copied, then the information is also carried in the copy. On the other hand, the main goal of steganography is to hide secret information in the other cover media (video, audio or image) so that other persons will not notice the presence of the information. This is a major distinction between this method and the other methods of covert exchange of information because, for example, in cryptography, the individuals notice the information by seeing the coded information but they will not be able to comprehend the information. However, in steganography, the existence of the information in the sources will not be noticed at all. Although steganography is separate and different from cryptography, but they are related in the way that they both are used to protect valuable information. (Shirali-Shahreza, 2006) 1

2 From here emerged the urgent need to find new techniques alternative organisation to overcome these weaknesses, giving rise to conceal information technology (Information Hiding), which are based on a different principle to the idea of organisation, where they are buried information (Information Embedding) within other media carrier, and making them aware (Imperceptible) by hackers and attackers, and so are the public domain of information to users of the network, while the content monopoly "on the relevant agencies, which alone knows how to extract content. (Asylum, 2001) 1.2 Hide Information Technical Hide information is the general title for two types of techniques, the first type used to protect information from observers and attackers allegedly writing covered (Covered Writing), or in other words (Steganography), which is the subject of research, and the second type, is used to demonstrate the intellectual property rights (Intellectual Property), or to ensure reliability (Authentication), is called (Digital Watermarking) (Jajodia, 2001) 1.3 Steganography VS Watermarks: Even though both of two technical works using the same principle but there are differ in some how. Scores of water is to hide the data relatively few "often" what is a legitimate owner of authors digital signature (Digital Authors Signature), documenting the company (Company Logo), the right of reproduction information (Copyright Information) or confidential unique figures (Fingerprinting), and these are all means to establish a reference point downloads the same. (Huang & Teo,, 1998; Rabinovich,,1999; Sellers, 1999) 2

3 The system usually coverage used large amounts of data to be uncovered in other media have nothing to do with the data embedded on the launch, but are a receptacle to contain such data to protect them from discovery. The researcher concerns more about Steganography in this project. Thus more literature has been conducted as follows: Steganography Definition All researchers agree that the term is derived from the Greeks and that there were different points of view on some of the words that came out of this term and include some of them below in relation to the sources. This term derived from Greek, means writing a term covered (Covered Writing), or conceal writing (Hiding Writing). The terminology (Steganography) came from the Greeks and consists of movie (Steganos) means covered or closed and (Graphy) means writing or painting. These mean writing a term covered (Covered Writing). Steganography word can be defined as writing covered (Covered Writing), which is derived from the Greek word.( Johnson & Jajodia, 2001). Thus the definition (Steganography) the art of concealment and transfer data through the data again host or Carrier, but harmful harmless transmitters for those data do not allow any enemy or observers to discover that there is confidential data Steganography throughout History One of the latest techniques that have been used in this area by researchers at the Mount Sinai School MOUNT SINAI Medical in New York New York in 1999, as they managed to hide the secret texts in Chromosome Strand human DNA by using a technique called genetic system coverage (Genomic Steganography), and by placing signs resolution to be agreed upon in the nuclei chromosomes and then integrate these with millions sentences and sent to the other end. To extract the secret message is 3

4 soaking get special distinction sentences used on the other and then placed under the microscope to extract the required text.( Clelland, Risca & Bancroft, 1999). The oldest Authentications on Steganography taken from the legendary stories Greeks Herodotus and then back to the fifth century BC, these sources indicate that they felt they fly head of the Messenger and then write the secret letter in the head (Flores, 2001), leaving hair to grow then be sent to the required which is a re-extraction letter. (Johnson & Jajodia, 2001; Zaidan., 2008). Authentications and other writing secret messages on the wood panels and then covered wax and will be hid those writing panels appear free of anything. And they were killing their animals as rabbit example corner confidential letter inside it. Other means that the common use since the first century AD, invisible inks Invisible Inks, which was able to write a confidential letter with any other nonvalue-confidential and usually write between lines, for example those rabbis some fruit juices Fruit Juices, milk, urine, vinegar, and all these species become dark and visible when exposed to heat the written document. Then these kinds of inks evolved with the evolution of science chemical was used vehicles carrying chemical characteristics of the same old species with a more accurate and efficient have been used during the First and Second World Wars in the military secrecy of correspondence. Other technical been used during World War II is sending a message hidden within another message is not relevant, and based on the idea of a nomination letters every word of the letter counterfeit representation of characters from the characters letter requested confidentiality. (Johnson & Jajodia, 2001) Moreover, there are numerous ideas for the same method is used to be more than characters, or take certain words or phrases within the text fake and leaving the rest. Finally, it should be noted that the senior researcher in the area of concealment and science-based organization itself is German Johannes Trithemius) between , and the oldest books in the area of coverage Posted by Gaspari Schotti) in

5 in the name of (Steganographyica) and (400) contains a page where all the ideas included (Trithemius) Steganography and Century Event Finally, it should be noted here that some research in this area confirm that one of the most important reasons for the success of an attack atheist eleven of September 2001 is the use of implementing the system coverage in all their contacts across global communications network (Internet), which missed opportunity on the United States of America to discover their plans even with their contacts and assault techniques in the area of secrecy and intelligence. Rumors about terrorists using steganography started first in the daily newspaper USA Today on February 5, 2001 in two articles titled "Terrorist instructions hidden online" and "Terror groups hide behind Web encryption". In July of the same year, the information looked even more precise: "Militants wire Web with links to jihad". (Flores, 2001; Asylum, 2001; Cullagh, 2002) 1.4 Problem Background Depend feature is that the concealment of all samples cover the same percentage, and can thus determine the percentage of concealment soon to know the volume and type of cover technique used, as well as to this method achieve the highest rate at each hide application. In the field of Steganography, some terminology has developed. The adjectives ' concealment ' defined at the information hiding workshop held in Cambridge, England. The term "concealment" refers to description of the original, innocent massage, data, audio, video, and so on. (Zaidan, 2008) 5

6 1.5 Problem Statement The problem in the hiding information or Steganography is the size of data that user want to embed inside the multimedia file, image is one of the multimedia file, the most commend method for hiding information in the image is LSB, LSB is efficient instead of that it s not easy to analysis, however, it is not effective in term of the data hidden quantity, all researchers agreed the fact that the size of data hidden is a problem in that particular area, the other problem that faced there, in fact if we try to increase the quantity of data in the image there will be a suspect changes which become clear to human eyes, for instance, this research will face a challenge that high rate data hidden without affecting the images quality, there are many trends that needs to be fallowed, initially; how can the new algorithm increase the amount of data, then what is the feature in the new image, how can the new algorithm deal with, all this items will be discuss in-depth in this research by suggest an enhancement to the work of hiding information in the image using the human vision system.(zaidan, 2008) As a summery, the main problems in the Steganography fallow as: (Othman, 2009) The size of data hidden Quality of image Algorithms that apply should also cover the gray level image Level of data protecting The level of suspecting This research will try to improve and enhance LSB algorithm, while LSB faced a problem on the 3 rd LSB, its clear to anyone the distortion in the images after use the 3rd LSB to embed the data; this distortion located on the blue color, and the complexity of the image texture, these points will be discuss on chapter three (Othman, 2009; Ziadan, 2008) 6

7 Starting from LSB which can hide 12.5 % in the image, in this research the author will try to enhance and develop a new LSB algorithm in which the author will try to come out with a better result for both image quality and the quantity of data hidden. The suggest algorithms will be two approaches; the approach without any limitations on the type of images being used and can reach up to 33.3% of size of hidden data, and the second one is the 4th LSB approach which increase the amount of hidden data but with certain limitations on the type of images chosen. All result on this project will be tested by a survey; this survey will be recorded for the master project under the faculty of computer Science and IT, University of Malaya, the tested image will be on more than 300 image from various extensions such as BMP, JPG, JPEG, this images will be acted by"1st LSB, 2 nd LSB, 3rd LSB, (3-3-2) LSB the special solution for the 3rd LSB, 4 th (LSB) 7

8 1.6 Objectives and Scope of the Thesis The aims and scopes of researcher to complete this thesis can be summarized as follows: Objectives: i) To formulate an algorithm based on data hidden technique in the image to higher the quantity of hidden data with out affecting the quality of images ii) To develop a system based on the algorithm established above. iii) To collect data and evaluate the accuracy of the algorithm by conducting a study on a survey for the images before and after hidden data iv) To act a new stego-analysis approach on the image to evaluate the new algorithm Research Scope The scope of the study encompasses: i) This research will focus on hidden data in image ii) iii) Hide information using HVS and pure Steganography Study the texture feature on image after increase the data hidden and its relation with the quality of image iv) Human survey will be involve on the test of the image 8

9 1.7 Research Schedule Time The proposed schedule for the Master thesis is shown in table 1: Table 1-1: Master thesis schedule for one year. Janua ry Februa ry Marc h April May Proposal Collecting Data Chapter 1, 2 First Result Chapter 3 Jun July August Septemb er Final Test Chapter 4, 5, 6 First Draft Final 9

10 1.8 Thesis Layout The remaining parts of this research text will be organized as following: CHAPTER TWO: the common methods that are applied in computer by using Multimedia files like text, images and sound. Then the limitations and disadvantages of these methods will be discussed. Discourse strength and weakness factors of Steganography, and attacking techniques on hidden information, also countermeasures against attacks in order to increase the system s efficiency CHAPTER THREE: the practical work the methods and techniques that will apply and developed stated media. New method has been proposed to hide information are proposed for increasing the efficiency of hiding in the image files by making use of Human Visible System (HVS) characteristics. CHAPTER FOUR: discuses the system implement, explain the main processing in the system and how it s going to display the result, how to deal with image, what is the concept that used in the system. CHAPTER FIVE: discuses the results that represent the output of the algorithms comparing with input from size, quality and the human eyes suspecting to the changes CHAPTER SIX: future work that proposed techniques gave very efficient results by increasing hiding ratio with imperceptible way. 10