Outer-totalistic Cellular Automata Research Articles

A Novel Edge Detection Algorithm Based on Outer Totalistic Cellular Automata

Edge detection is a key technique in image processing. The detected edge quality has a direct and significant impact on performance. There is a multitude of methods for edge detection but they are strongly associated with the application and the quality of the images. However, more precise outcomes and a reduced execution time remain the primary objectives for extracting edges. To address these issues, we propose a novel technique based on a complex system called Cellular Automata (CA). They are successfully applied in edge detection due to their simplicity and local interactions. This undertook shed new light on a novel method using Outer Totalistic Cellular Automata (OTCA) to perform efficiently edge detection. We have tested images from Berkeley dataset. RMSE and SSIM are used as fitness functions for estimating numerical performance of OTCA rules. Comparisons were made with classical edge detectors like: Canny, Scharr, Sobel, Roberts. Experimental results showed that OTCA rules provide excellent performance and outperforms other edge detectors in terms of precision and execution time, particularly when dealing with noisy images.

Digital Image Encryption Based on Chaotic Cellular Automata

Cellular automata are dynamical systems, discrete in terms of both space and time. Many cellular automata are capable of generating chaos and are well suited for applications like digital image encryption and scrambling. Various cellular automata-based digital image scrambling techniques have been proposed in literature. An adversary may have access to a set of images from which the particular image is scrambled. The problem with these techniques in this particular case is that an adversary may be able to find out the true content of the scrambled image just by comparing its histogram with the histograms of a suspected set of images. In this paper, a secure digital image encryption technique based on outer totalistic cellular automata is proposed that modifies the histogram of the scrambled image so that it is difficult to guess the true content carried in the digital image.

Characteristics of fractal cellular automata constructed from linear rules

Cellular automata (CAs) have played a significant role in the study of complex systems. Recently, the recursive estimation of neighbors (REN) algorithm was proposed to extend a CA rule with a unit rule radius to rules with larger radii. This framework enables the construction of non-uniform CAs comprising cells that follow different CA rules. A non-uniform CA, referred to as fractal CA (F-CA), which comprises fractally arranged cells, inherits certain characteristics of basic CAs, including pattern replicability and time-reversibility of linear rules. In this paper, F-CAs based on linear rules, particularly the elementary CA #90 and #150, and life-like CA B1357S1357 and B1357S02468 are investigated. Cells in the F-CAs of #90 and B1357S1357 are separated into groups by their rule radius and each group has an independent lifetime. The explicitly constructed inverse rule of F-CA of #150 is more complex than that of F-CA. The complexity of the F-CA of B1357S02468 and its inverse CA is demonstrated by image scrambling. The F-CAs can be applied to encoding and decoding processes for encryption systems.

Cellular automata-based approach for salt-and-pepper noise filtration

Application of cellular automata (CA) to digital image processing has achieved considerable attention in last several years. CA are now employed in noise filtration of digital images; particularly many CA-based impulse noise filters have been proposed. Salt-and-pepper noise is a special kind of impulse noise and is introduced in an image during transmission over transmission media by external noise sources like atmospheric disturbances, or due to corrupted hardware memory locations or fault in camera sensors. In this paper, we present five salt-and-pepper noise filters based on modifications of outer totalistic cellular automata (OTCA) with the adaptive neighborhood. Use of OTCA model makes the proposed filters computationally simple on one hand and the use of adaptive neighborhood help the filters to provide efficient noise filtration at varying noise densities on the other. Comparative analysis of these filters followed by comparison with several standard and CA-based filters in terms of peak signal to noise ratio (PSNR) and structural similarity (SSIM) index is presented.

Cellular automata in fractal arrangement

Cellular automata (CAs) have been successfully used to investigate complex phenomena across a broad range of research fields. Standard CAs can be extended by applying a novel algorithm known as the recursive estimation of neighbors. This process allows the construction of non-uniform CAs that are composed of cells with different perception areas parameterized by an extra radius. This paper proposes a non-uniform CA called Fractal CA (F-CA), which is composed of cells with self-similar fractal arrangement. By focusing on the extension of 1D elementary CAs, certain characteristics of standard CAs are carried over into F-CAs, including time reversibility of the linear rules. F-CAs based on 2D outer-totalistic CAs are also mentioned briefly.

Design of image cipher using life-like cellular automata and chaotic map

Abstract Recently, a number of image ciphers using cellular automata (CA) or combined with chaotic maps have been proposed. However, most of them suffer from some intrinsic drawbacks such as small rule space, low diffusion and no explicit classification of CA rules. To overcome these drawbacks, this paper presents a novel image cipher based on Life-like cellular automata and chaos. The proposed image cipher consists of two sub-processes: permutation and substitution. In the permutation, a two-dimensional Logistic-adjusted-Sine map (2D-LASM) with excellent properties is adopted to shuffle the pixel positions. In the substitution, a second-order Life-like CA with a balanced rule is employed. The balanced rules make the distribution of 0 and 1 in Life-like CA gradually be in equilibrium during the process of iteration. Second-order CA can preserve the result of CA after each iteration to obtain the reversibility. Furthermore, to resist chosen-plaintext and known-plaintext attacks, the algorithm controls the initial conditions of 2D-LASM by the key and the weighted histogram of the plain-image. Theoretical analysis and experimental results both show that the proposed scheme has prominent cryptographic performances and can resist the common attacks effectively, which is very suitable for image encryption.

An edge detection method using outer Totalistic Cellular Automata

A number of Cellular Automata (CA)-based edge detectors have been developed recently due to the simplicity of the model and the potential for simultaneous removal of different types of noise in the process of detection. This paper introduced a novel edge detector using Outer Totalistic Cellular Automata. Its performance has been compared with other recently developed CA-based edge detectors, in addition to some classic methods, through testing images from a public library. Visual and quantitative measurement of similarity with manually marked correct edges confirmed the superiority of the proposed method over conventional and state-of-the-art CA-based edge detectors.

Chaotic encryption method based on life-like cellular automata

A chaotic encryption algorithm is proposed based on the “Life-like” cellular automata (CA), which acts as a pseudo-random generator (PRNG). The paper main focus is to use chaos theory to cryptography. Thus, CA was explored to look for this “chaos” property. This way, the manuscript is more concerning on tests like: Lyapunov exponent, Entropy and Hamming distance to measure the chaos in CA, as well as statistic analysis like DIEHARD and ENT suites. Our results achieved higher randomness quality than others ciphers in literature. These results reinforce the supposition of a strong relationship between chaos and the randomness quality. Thus, the “chaos” property of CA is a good reason to be employed in cryptography, furthermore, for its simplicity, low cost of implementation and respectable encryption power.

General algorithm for two-dimensional totalistic cellular automata

Multi-site coding techniques allow fast simulations of cellular automata that are economical in the use of memory. In these techniques the transition rule must be expressed using only bitwise operations. We present an algorithm for the simulation of generic totalistic and outer totalistic cellular automata which uses a multi-site coding technique. The algorithm is based on the careful use of (a) improvements over the canonical forms by using the exclusive-or operation, (b) optimal storage of the configuration in the computer memory, and (c) appropriate construction of stochastic rules. Items (b) and (c) of the method can be also applied to non-totalistic automata in any dimension.