Conventional encryption techniques are usually applicable for text data and often unsuited for encrypting multimedia objects for two reasons. Firstly, the huge sizes associated with multimedia objects make conventional encryption computationally costly. Secondly, multimedia objects come with massive redundancies which are useful in avoiding encryption of the objects in their entirety. Hence a c...

In many practical scenarios, image encryption has to be conducted prior to image compression. This has led to the problem of how to design a pair of image encryption and compression algorithms such that compressing the encrypted images can still be efficiently performed. In this paper, we design a highly efficient image encryption-thencompression (ETC) system, where both lossless and lossy comp...

In many practical scenarios, image encryption has to be conducted prior to image compression. This has led to problem of how to design a pair of image encryption and compression algorithms such that compressing the encrypted images can still be efficiently performed. In this paper, we design highly efficient image encryption-then-compression (ETC) system, where both the lossy and lossless compr...

The most important factors in e-applications are security, integrity, non-repudiation, confidentiality and authentication services. Nowadays, confidentiality and security of the digital images attract more the attention more, especially when these digital images are transmitted over the internet or stored in some types of memory. Many different image encryption algorithms and techniques have be...

The combination of chaotic theory and cryptography forms an important field of information security. In the past decade, chaos based image encryption is given much attention in the research of information security and a lot of image encryption algorithms based on chaotic maps have been proposed. Due to some inherent features of images like bulk data capacity and high data redundancy, the encryp...

The rapid evolution of imaging and communication technologies has transformed images into a widespread data type. Different types of data, such as personal medical information, official correspondence, or governmental and military documents, are saved and transmitted in the form of images over public networks. Hence, a fast and secure cryptosystem is needed for high-resolution images. In this p...

During the recent years several chaotic image encryption algorithms based on one dimensional (1-D) have been proposed, but the drawbacks of small key space, low speed, and low security in 1-D chaotic cryptosystems are obvious. This paper proposes a new image encryption technique based on 1-D and 2-D chaotic maps which provide more security and big key space. The 1-D chaotic system is induced fr...

In this paper we show how to use two-colored pixels as a generic tool for image processing. We apply twocolored pixels as a basic operator as well as a supporting data structure for several image processing applications. Traditionally, images are represented by a regular grid of square pixels with one constant color each. In the twocolored pixel representation, we reduce the image resolution an...