“Multimedia Steganography with Cipher Text

and Compression “

Synopsison

Department Of

INFORMATION TECHNOLOGY

SUBMITTED BY:

NAME OF STUDENTS ROLL NO.

INTRODUCTION

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 steganous meaning "covered or protected“ . Generally, messages will appear to be something else: images, articles, shopping lists, or some other cover text 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.

Operations of Steganography through a Data flow diagram:

TYPES OF STEGANOGRAPHY

TEXT STEGANOGRAPHY:

Steganography can be applied to different types of media including text, audio, image and video etc. However, text steganography is considered to be the most difficult kind of steganography due to lack of redundancy in text as compared to image or audio but still has smaller memory occupation and simpler communication. The method that could be used for text steganography is data compression.

Data compression encodes information in one representation into another representation. The new representation of data is smaller in size. One of the possible schemes to achieve data compression is Huffman coding. Huffman coding assigns smaller length code words to more frequently occurring source symbols and longer length code words to less frequently occurring source symbols.

AUDIO STEGANOGRAPHY:

In a computer-based audio steganography system, secret messages are embedded in digital sound. The secret message is embedded by slightly altering the binary sequence of a sound file. Existing audio steganography software can embed messages in WAV, AU, and even MP3 sound files.

Embedding secret messages in digital sound is usually a more difficult process than embedding messages in other media, such as digital images. In order to conceal secret messages successfully, a variety of methods for embedding information in digital audio have been introduced.

VIDEO STEGANOGRAPHY:

It is a technique to hide any kind of files in any extension into a carrying Video file. This project is the application developed to embed any kind of data(File) in another file, which is called carrier file. The carrier file must be a video file. It is concerned with embedding information in an innocuous cover media in a secure and robust manner. This system makes the Files more secure by using the concepts Steganography and Cryptography.

IMAGE STEGANOGRAPHY:

The original image’s integrity is maintained and the decompressed image output is bit-by-bit identical to the original image input. The most popular image formats that use lossless compression is GIF (Graphical Interchange Format) and 8-bit BMP (a Microsoft Windows bitmap file).

Compression plays a very important role in choosing which steganographic algorithm to use. Lossless compression, on the other hand, never removes any information from the original image, but instead represents data in mathematical formulas. Lossy compression techniques result in smaller image file sizes, but it increases the possibility that the embedded message may be partly lost due to the fact that excess image data will be removed. Lossless compression though, keeps the original digital image intact without the chance of lost, although is does not compress the image to such a small file size.

ADVANTAGES AND DISADVANTAGES:

Steganography is beneficial for securely storing sensitive data, such as hiding system passwords or keys within other files. However, it can also pose serious problems because it's difficult to detect. Network surveillance and monitoring systems will not flag messages or files that contain steganographic data. Therefore, if someone attempted to steal confidential data, they could conceal it within another file and send it in an innocent looking email.

DETECTING STEGANOGRAPHY MISUSE:

There are two methods for detecting steganographically-encoded data: visual steganalysis and statistical steganalysis. The visual method compares a copy of the source file with the suspect file by running a hash against the source file and checking that it matches the hash on the suspect copy. Statistical steganalysis compares theoretically expected frequency distributions of message content with the frequency distribution of the suspected file. Because the cover text has to be modified to store the hidden data, there are usually detectable signs within the cover text's normal characteristics that can be used to reveal the hidden message. For example, when running a histogram on an image, there should be random spikes, but if the histogram is flat or has one large spike, it's likely the image contains hidden information.

CONCLUSION :

Steganography has its place in security. It is not intended to replace cryptography but supplement it. Hiding a message with steganography methods reduces the chance of a message being detected. However, if that message is also encrypted, if discovered, it must also be cracked (yet another layer of protection).

There are an infinite number of steganography applications. This paper explores a tiny fraction of the art of steganography. It goes well beyond simply embedding text in an image. Steganography does not only pertain to digital images but also to other media (files such as voice, other text and binaries; other media such as communication channels, the list can go on and on).

Thus, we have designed a software which has a really has a very good application in real world. It will be notable feature as this system is very easy and customizable makes it useful to wide variety of the users for Security purposes.