A Survey on Digital Image Steganography

Abstract

The fast growth in communication technologies and the increased availability of the public networks (Internet) facilitated data transfer. However the public communication channels are vulnerable to security attacks that may lead to unauthorized access to some information. Encryption has been used to persist and prevent these attacks. But when the information is decrypted it will be exposed to the attackers again and it will not have any security protection. Steganography is the science of embedding the secret messages inside other medium files (text, audio, image, and video) in a way that hides the existence of the secret message at all. Steganography applies an embedding process in which the redundant bits of the medium are replaced by the bits of the secret message. Image Steganography is the field of steganography in which the medium that used to carry the secret data is a digital image. Image Steganography is an important area of research in the recent years. This article reviews the steganography based on digital images; illustration of the concept and the common approaches are discussed. Also Steganalysis which is the science of attacking steganography will be briefly discussed. Keywords— digital image steganography; spatial domain embedding; transform domain embedding; cover-image; stego-image; wavelet transform; Steganalysis