In [4], we introduced the alternating greedy expansion of integers, which turned out to be useful in several left-to-right algorihms in cryptography. In this paper, we collect known results about this alternating greedy expansion and complement it with other useful properties and algorithms. In the second part, we apply it to give an algorithm for computing a joint expansion of d integers of mi...

Flash memories find wide use in storing data in any application. Data deletion in flash memories involves making the data unreliable on the device. As contents get deleted in the flash memory, time is consumed in deleting the data on the flash permanently. This paper proposes a method to make the contents of the deleted blocks in the flash memory unreliable. The proposed method makes data unrel...

In this paper, we propose a new method of non-adaptive LSB steganography in still images to improve the embedding efficiency from 2 to 8/3 random bits per one embedding change even for the embedding rate of 1 bit per pixel. The method takes 2-bits of the secret message at a time and compares them to the LSBs of the two chosen pixel values for embedding, it always assumes a single mismatch betwe...

One of the most frequent operations in modern cryptosystems is a multi-scalar multiplication with two scalars. Common methods to compute it are the Shamir method and the Interleave method whereas their speed mainly depends on the (joint) Hamming weight of the scalars. To increase the speed, the scalars are usually deployed using some general representation which provides a lower (joint) Hamming...

We present an implementation of table constraints in CLP(FD). For binary constraints, the supports of each value are represented as a finite-domain variable, and action rules are used to propagate value exclusions. The bit-vector representation of finite domains facilitates constant-time removal of unsupported values. For n-ary constraints, we propose pair-wise arc consistency (AC), which ensur...

This paper revisits the steganalysis method involving a Weighted Stego-Image (WS) for estimating LSB replacement payload sizes in digital images. It suggests new WS estimators, upgrading the method’s three components: cover pixel prediction, least-squares weighting, and bias correction. Wide-ranging experimental results (over two million total attacks) based on images from multiple sources and ...

This paper introduces a new privacy filter adopted in the context of the DPT (Drone Protect Task) at MediaEval Benchmark 2015. Our proposed filter protects privacy by visually replacing sensitive RofI (Regions of Interest) by its shapes. A combination of steganography and scrambling is used in order to make this filter. Once the scrambling is applied on the pixels of the RofI, its MSB (Most Sig...

The central topic of this paper is the alternating greedy expansion of integers, which is defined to be a binary expansion with digits {0,±1} with the property that the nonzero digits have alternating signs. We collect known results about this alternating greedy expansion and complement it with other useful properties and algorithms. In the second part, we apply it to give an algorithm for comp...

In today’s information age, information sharing and transfer has increased exponentially. The information vulnerable to unauthorised access and interception, while in storage or transmission. The threat of an intruder and Steganalysis accessing secret information for sharing information over an unsecure or covert communication channels are vulnerable to intruder attacks. Although, these techniq...

Steganography consist of concealing secret information in a cover object to be sent over a public communication channel. It allows two parties to share hidden information in a way that no intruder can detect the presence of hidden information. This paper presents a novel steganography approach based on pixel location matching of the same cover image. Here the information is not directly embedde...