Steganalysis based on JPEG compatibility

Other Title(s)

تحليل الكتابة المخفية المبني على أساس تناسقية ال JPEG

Dissertant

al-Tai, Mayy Muwaffaq Abbas

Thesis advisor

Abbud, Luayy Kazim

University

University of Baghdad

Faculty

College of Science

Department

Department of Computer Science

University Country

Iraq

Degree

Master

Degree Date

2004

English Abstract

Steganalysis is a relatively new branch of research.

While steganography deals with techniques for hiding information.

The goal of steganalysis is to detect and/or estimate potentially hidden information from observed data with little or no knowledge about the steganography algorithm and/or its parameters.

In general, extraction of the secret message could be a harder problem than mere detection.

In this research we describe a new steganalytic technique that can detect modifications in color images, such as those due to steganography and watermarking, as long as the original image (the cover image) has been previously stored in the JPEG format.

The steganalytic technique starts with extracting the JPEG quantization matrix by carefully inspecting the clusters of DCT coefficients.

Then, each block is analyzed if its pixels values are truncated values of an inverse DCT transform of a set of coefficients quantized with the extracted quantization matrix.

A simple necessary condition is derived that makes the analysis computationally feasible.

If the corresponding quantized DCT coefficients are found, the block is termed compatible, otherwise it is not.The steganalytic technique will work for many steganographic methods such as (S-TOOLS4, HIDE4PGP, and HIDE IN SEQUENTIAL LSB), except the methods that embed information directly into the compressed JPEG stream.

One of the important conclusions drawn is that a new value for the equation of the quality condition adopted drawn from the result rather than the mentioned value in the researchs.

This adopted system can be used with true color images rather than gray level images

Main Subjects

Information Technology and Computer Science

No. of Pages

103

Table of Contents

• APA
• MLA
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Language

English

Data Type

Arab Theses

Record ID

BIM-604775