05-07-2012, 04:30 PM
MORE SECURE STEGANOGRAPHY METHOD IN SPECIAL
[attachment=26907]
INTRODUCTION
Since the rise of the Internet, one of the most important factors of information technology and communication has been the security of information. Cryptography was created as a technique for securing the secrecy of communication and many different methods have been developed to encrypt and decrypt data in order to keep the message secret. Unfortunately it is sometimes not enough to keep the contents of a message secret, it may also be necessary to keep the existence of the message secret. The technique used to implement this, is called steganography.
Steganography is the art of secret communication. Its purpose is to hide the very presence of communication as opposed to cryptography whose goal is to make communication unintelligible to those who do not possess the right keys. Digital images, videos, sound files, and other computer files that contain perceptually irrelevant or redundant information can be used as “covers” or carriers to hide secret messages. After embedding secret message into the cover-image, a so-called stego image is obtained. It is important that the stego-image does not contain any detectable artifacts due to message embedding. A third party could use such artifacts as an indication that a secret message is present.
ABOUT THE PROJECT
In this project, an image is used as a carrier to hide image data. This is called Image Steganography. Least significant bit (LSB) is the simplest form of steganography. LSB is based on inserting data in the least significant bit of pixels, which lead to a slight change on the cover image that is not noticeable to human eye. Since this method can be easily cracked, it is more vulnerable to attacks.
To increase the security and the size of stored data, a new adaptive LSB technique is used. Instead of storing the data in every least significant bit of the pixels, this technique tries to use more than one bit in a pixel in such a way that this change will not affect the visual appearance of the host image. It uses the side information of neighboring pixels to estimate the number of bit which can be carried in the pixels of the host-image to hide the secret data.
OBJECTIVE OF STUDY
To increase the security and the size of stored data, a new adaptive LSB technique is used. Instead of storing the data in every least significant bit of the pixels, this technique tries to use more than one bit in a pixel in such a way that this change will not affect the visual appearance of the host image. It uses the side information of neighboring pixels to estimate the number of bit which can be carried in the pixels of the host-image to hide the secret data.
MOTIVATION OF STUDY
Least significant bit (LSB) is the simplest form of steganography. LSB is based on inserting data in the least significant bit of pixels, which lead to a slight change on the cover image that is not noticeable to human eye. Since this method can be easily cracked, it is more vulnerable to attacks.
ABOUT STEGANOGRAPHY
Steganography is the art and science of writing hidden messages in such a way that no one, apart from the sender and intended recipient, suspects the existence of the message, a form of security through obscurity. The word steganography is of Greek origin and means "concealed writing" from the Greek words steganos meaning "covered or protected", and graphein meaning "to write". The first recorded use of the term was in 1499 by Joharnnes Trithemius in his Steganographia, a treatise on cryptography and steganography disguised as a book on magic. Generally, messages will appear to be something else: images, articles, shopping lists, or some other covertext and, classically, the hidden message may be in invisible ink between the visible lines of a private letter.
The advantage of steganography, over cryptography alone, is that messages do not attract attention to themselves. Plainly visible encrypted messages—no matter how unbreakable—will arouse suspicion, and may in themselves be incriminating in countries where encryption is illegal Therefore, whereas cryptography protects the contents of a message, steganography can be said to protect both messages and communicating parties.
Steganography includes the concealment of information within computer files. In digital steganography, electronic communications may include steganographic coding inside of a transport layer, such as a document file, image file, program or protocol. Media files are ideal for steganographic transmission because of their large size. As a simple example, a sender might start with an innocuous image file and adjust the color of every 100th pixel to correspond to a letter in the alphabet, a change so subtle that someone not specifically looking for it is unlikely to notice it.
Although steganography is an ancient subject, the modern formulation of it is often given in terms of the prisoner’s problem proposed by Simmons, where two inmates wish to communicate in secret to hatch anescape plan. All of their communication passes through a warden who will throw them in solitary confinement should she suspect any convert communication.
[attachment=26907]
INTRODUCTION
Since the rise of the Internet, one of the most important factors of information technology and communication has been the security of information. Cryptography was created as a technique for securing the secrecy of communication and many different methods have been developed to encrypt and decrypt data in order to keep the message secret. Unfortunately it is sometimes not enough to keep the contents of a message secret, it may also be necessary to keep the existence of the message secret. The technique used to implement this, is called steganography.
Steganography is the art of secret communication. Its purpose is to hide the very presence of communication as opposed to cryptography whose goal is to make communication unintelligible to those who do not possess the right keys. Digital images, videos, sound files, and other computer files that contain perceptually irrelevant or redundant information can be used as “covers” or carriers to hide secret messages. After embedding secret message into the cover-image, a so-called stego image is obtained. It is important that the stego-image does not contain any detectable artifacts due to message embedding. A third party could use such artifacts as an indication that a secret message is present.
ABOUT THE PROJECT
In this project, an image is used as a carrier to hide image data. This is called Image Steganography. Least significant bit (LSB) is the simplest form of steganography. LSB is based on inserting data in the least significant bit of pixels, which lead to a slight change on the cover image that is not noticeable to human eye. Since this method can be easily cracked, it is more vulnerable to attacks.
To increase the security and the size of stored data, a new adaptive LSB technique is used. Instead of storing the data in every least significant bit of the pixels, this technique tries to use more than one bit in a pixel in such a way that this change will not affect the visual appearance of the host image. It uses the side information of neighboring pixels to estimate the number of bit which can be carried in the pixels of the host-image to hide the secret data.
OBJECTIVE OF STUDY
To increase the security and the size of stored data, a new adaptive LSB technique is used. Instead of storing the data in every least significant bit of the pixels, this technique tries to use more than one bit in a pixel in such a way that this change will not affect the visual appearance of the host image. It uses the side information of neighboring pixels to estimate the number of bit which can be carried in the pixels of the host-image to hide the secret data.
MOTIVATION OF STUDY
Least significant bit (LSB) is the simplest form of steganography. LSB is based on inserting data in the least significant bit of pixels, which lead to a slight change on the cover image that is not noticeable to human eye. Since this method can be easily cracked, it is more vulnerable to attacks.
ABOUT STEGANOGRAPHY
Steganography is the art and science of writing hidden messages in such a way that no one, apart from the sender and intended recipient, suspects the existence of the message, a form of security through obscurity. The word steganography is of Greek origin and means "concealed writing" from the Greek words steganos meaning "covered or protected", and graphein meaning "to write". The first recorded use of the term was in 1499 by Joharnnes Trithemius in his Steganographia, a treatise on cryptography and steganography disguised as a book on magic. Generally, messages will appear to be something else: images, articles, shopping lists, or some other covertext and, classically, the hidden message may be in invisible ink between the visible lines of a private letter.
The advantage of steganography, over cryptography alone, is that messages do not attract attention to themselves. Plainly visible encrypted messages—no matter how unbreakable—will arouse suspicion, and may in themselves be incriminating in countries where encryption is illegal Therefore, whereas cryptography protects the contents of a message, steganography can be said to protect both messages and communicating parties.
Steganography includes the concealment of information within computer files. In digital steganography, electronic communications may include steganographic coding inside of a transport layer, such as a document file, image file, program or protocol. Media files are ideal for steganographic transmission because of their large size. As a simple example, a sender might start with an innocuous image file and adjust the color of every 100th pixel to correspond to a letter in the alphabet, a change so subtle that someone not specifically looking for it is unlikely to notice it.
Although steganography is an ancient subject, the modern formulation of it is often given in terms of the prisoner’s problem proposed by Simmons, where two inmates wish to communicate in secret to hatch anescape plan. All of their communication passes through a warden who will throw them in solitary confinement should she suspect any convert communication.