scholarly journals Selective Video Encryption Using the Cross Coupling of One-dimensional Logistic Maps

2021 ◽  
Vol 13 (5) ◽  
pp. 40-54
Author(s):  
Rohit S Malladar ◽  
◽  
Sanjeev R Kunte
Keyword(s):  
Performance Metrics ◽  
Signal To Noise Ratio ◽  
Logistic Map ◽  
Lookup Table ◽  
Data Conversion ◽  
Video Encryption ◽  
Major Research ◽  
One Dimensional ◽  
Visual Degradation ◽  
Video Format

H.264 videos have been the most shared type of video format in recent times and hence its security is a major issue. The techniques presented in the recent times incur complex computations. The major research objective is to design an efficient Chaotic Selective Video Encryption (CSVE) technique which can result in a better visual degradation of the encrypted video with less computational complexity. In the proposed work, in order to secure the H.264 videos, two one-dimensional logistic maps are cross coupled in the chaotic encryption technique which uses a lookup table for data conversion. The technique is evaluated using different performance metrics like Peak Signal to Noise Ratio (PSNR), entropy, statistical analysis etc along with the traditional logistic map. The work is compared with some recent techniques in terms of PSNR and was found out that the proposed technique has better encryption effect.

scholarly journals A Symmetric Key Multiple Color Image Cipher Based on Cellular Automata, Chaos Theory and Image Mixing

2021 ◽  
Vol 50 (1) ◽  
pp. 55-75
Author(s):  
K SundaraKrishnan ◽  
RAJA SP ◽  
JAISON B
Keyword(s):  
Cellular Automata ◽  
Performance Metrics ◽  
Color Image ◽  
Signal To Noise Ratio ◽  
Logistic Map ◽  
Public Network ◽  
Key Space ◽  
Image Cipher ◽  
Zigzag Pattern ◽  
Encrypted Images

The transmission of significant masses of sensitive and secret images over a public network is inevitable, and demands effective tools and technology to safeguard and conceal the data. In this paper, a symmetric multiple color image encryption technique is proposed by adopting a dual permutation and dual substitution framework. Firstly, the input images are combined into a large image and then segmented into many small and equal-sized pure-image elements. Secondly, using the elementary cellular automata Rule-30, these pure-image elements are permuted to obtain mixed-image elements. Thirdly, second-level permutation is undertaken on the mixed-image elements by applying zigzag pattern scanning. Fourthly, pixel values are substituted by employing the circular shift method; subsequently, second-level pixel substitution is realized through using chaotic random sequences from a 2D logistic map. Finally, the big encrypted image is segmented into smaller encrypted images. Additionally, the keys are calculated from the input images to attain input sensitivity. The efficiency of this method is quantified, based on the unified average changing intensity (UACI), information entropy, number of pixels change rate (NPCR), key sensitivity, key space, histogram, peak signal-to-noise ratio (PSNR) and correlation coefficient (CC) performance metrics. The outcome of the experiments and a comparative analysis with two similar methods indicate that the proposed method produced high security results.

Local Geometric Projection-Based Noise Reduction for Vibration Signal Analysis in Rolling Bearings

2008 ◽  
Author(s):  
Ruqiang Yan ◽  
Robert X. Gao ◽  
Kang B. Lee ◽  
Steven E. Fick
Keyword(s):  
Time Series ◽  
Phase Space ◽  
Noise Reduction ◽  
Signal Analysis ◽  
Signal To Noise Ratio ◽  
Multifractal Spectrum ◽  
Vibration Signal ◽  
Rolling Bearings ◽  
One Dimensional ◽  
Vibration Signal Analysis

This paper presents a noise reduction technique for vibration signal analysis in rolling bearings, based on local geometric projection (LGP). LGP is a non-linear filtering technique that reconstructs one dimensional time series in a high-dimensional phase space using time-delayed coordinates, based on the Takens embedding theorem. From the neighborhood of each point in the phase space, where a neighbor is defined as a local subspace of the whole phase space, the best subspace to which the point will be orthogonally projected is identified. Since the signal subspace is formed by the most significant eigen-directions of the neighborhood, while the less significant ones define the noise subspace, the noise can be reduced by converting the points onto the subspace spanned by those significant eigen-directions back to a new, one-dimensional time series. Improvement on signal-to-noise ratio enabled by LGP is first evaluated using a chaotic system and an analytically formulated synthetic signal. Then analysis of bearing vibration signals is carried out as a case study. The LGP-based technique is shown to be effective in reducing noise and enhancing extraction of weak, defect-related features, as manifested by the multifractal spectrum from the signal.

scholarly journals A Chaos based image Encryption Scheme using one Dimensional Exponential Logistic Map.

2019 ◽  
Vol 1 ◽  
pp. 223-237
Author(s):  
Terlumun Gbaden
Keyword(s):  
Correlation Coefficient ◽  
Chaotic Map ◽  
Logistic Map ◽  
Encryption Scheme ◽  
One Dimensional ◽  
Encryption And Decryption ◽  
Secret Keys ◽  
Encryption Decryption ◽  
Logistic Chaotic Map ◽  
Encrypted Images

The widespread use of images in various sectors of life makes its protection increasingly necessary and important. An improvement over encryption and decryption algorithm using exponential logistic chaotic map was proposed. In this work, we adopt an encryption/decryption strategy for colour images using the exponential logistic chaotic map. The proposed encryption/decryption algorithms are implemented in MATLAB for computer simulation. The experimental results indicate that the proposed algorithms can be used successfully to encrypt/decrypt images with secret keys. The performance analysis using histogram uniformity analysis and correlation coefficient show that the algorithms give larger space, quick speed and easy to realize. The encrypted images have good encryption effect and low correlation coefficient rendering it a good candidate for confidential and secure means of transmitting image information in untrusted networks.

scholarly journals Revisiting Twomey's approximation for peak supersaturation

2014 ◽  
Vol 14 (19) ◽  
pp. 25901-25930
Author(s):  
B. J. Shipway
Keyword(s):  
Lookup Table ◽  
Accurate Calculation ◽  
Cloud Droplets ◽  
Closed Expression ◽  
One Dimensional ◽  
Additional Information ◽  
Droplet Nucleation ◽  
Physically Based ◽  
Thermodynamic Conditions ◽  
Independent Variable

Abstract. Twomey's seminal 1959 paper provided lower and upper bound approximations to the estimation of peak supersaturation within an updraft and thus provides the first closed expression for the number of nucleated cloud droplets. The form of this approximation is simple, but provides a surprisingly good estimate and has subsequently been employed in more sophisticated treatments of nucleation parametrization. In the current paper, we revisit the lower bound approximation of Twomey and make a small adjustment which can be used to obtain a more accurate calculation of peak supersaturation under all potential aerosol loadings and thermodynamic conditions. In order to make full use of this improved approximation, the underlying integro-differential equation for supersaturation evolution and the condition for calculating peak supersaturation are examined. A simple rearrangement of the algebra allows for an expression to be written down which can then be solved with a single lookup table with only one independent variable for an underlying lognormal aerosol population. Multimode aerosol with only N different dispersion characteristics require only N of these one-dimensional lookup tables. No additional information is required in the lookup table to deal with additional chemical, physical or thermodynamic properties. The resulting implementation provides a relatively simple, yet computationally cheap and very accurate physically-based parametrization of droplet nucleation for use in climate and NWP models.

STABILIZATION OF CHAOTIC DYNAMICS OF ONE-DIMENSIONAL MAPS BY A CYCLIC PARAMETRIC TRANSFORMATION

1996 ◽  
Vol 06 (04) ◽  
pp. 725-735 ◽  
Author(s):  
ALEXANDER Yu. LOSKUTOV ◽  
VALERY M. TERESHKO ◽  
KONSTANTIN A. VASILIEV
Keyword(s):  
Periodic Orbits ◽  
Chaotic Dynamics ◽  
Chaotic Maps ◽  
Logistic Map ◽  
Exponential Map ◽  
One Dimensional ◽  
Stable Periodic ◽  
One Dimensional Maps ◽  
Parameter Values ◽  
Parametric Transformation

We consider one-dimensional maps, the logistic map and an exponential map, in those sets of parameter values which correspond to their chaotic dynamics. It is proven that such dynamics may be stabilized by a certain cyclic parametric transformation operating strictly within the chaotic set. The stabilization is a result of the creation of stable periodic orbits in the initially chaotic maps. The period of these stable orbits is a multiple of the period of the cyclic transformation. It is shown that stabilized behavior cannot be destroyed by a weak noise smearing of the required parameter values. The regions where the behavior stabilization takes place are numerically estimated. Periods of the created stabile periodic orbits are calculated.

To Mitigate the Effect of Cross-Phase Modulation by Employing PC-DCF Technique in Multi-Tone RoF System

2018 ◽  
Vol 0 (0) ◽  
Author(s):  
Namita Kathpal ◽  
Amit Kumar Garg
Keyword(s):  
Optical Networks ◽  
Wavelength Division Multiplexing ◽  
Phase Modulation ◽  
Performance Metrics ◽  
Signal To Noise Ratio ◽  
Optical Signal ◽  
Input Power ◽  
System Capacity ◽  
Bit Rate ◽  
Cross Phase Modulation

AbstractIt is known that the high bandwidth demands are accomplished by deploying the concept of wavelength division multiplexing in optical networks which involves the transmission of multiple wavelength signals spaced very close to each other. Due to closely spaced wavelengths, the signal power of one channel phase modulates the adjacent channel which in turn produces nonlinear effects such as cross-phase modulation (XPM), self-phase modulation (SPM) and four-wave mixing (FWM). Thus, in this paper, PC-DCF (pre-compensating dispersion compensating fiber) technique has been demonstrated and evaluated in the transmission link to compensate the XPM effects, and this result seems to significantly enhance w.r.t. transmission performance and system capacity considering performance metrics such as Optical Signal to Noise Ratio (OSNR), bit rate, Q-factor and bit error rate (BER). It is evident from the simulation results as well as through mathematical modeling that the proposed technique (PC-DCF) provides optimum results at the channel spacing of 100 GHz, bit rate of 10 Gbps and input power of 5 mW which collectively provides a 5 dB increase in OSNR as compared to the existing compensating technique.

scholarly journals An ILM-cosine transform-based improved approach to image encryption

2020 ◽  
Author(s):  
Mohit Dua ◽  
Arun Suthar ◽  
Arpit Garg ◽  
Vaibhav Garg
Keyword(s):  
Image Encryption ◽  
High Efficiency ◽  
Initial Conditions ◽  
Signal To Noise Ratio ◽  
Logistic Map ◽  
Random Order ◽  
Chaotic Sequence ◽  
Dynamical Behaviour ◽  
Original Position ◽  
Digital Information

Abstract The chaos-based cryptography techniques are used widely to protect digital information from intruders. The chaotic systems have some of special features that make them suitable for the purpose of encryption. These systems are highly unpredictable and are highly sensitive or responsive to the initial conditions, also known as butterfly effect. This sensitive dependence on initial conditions make these systems to exhibit an intricate dynamical behaviour. However, this dynamical behaviour is not much complex in simple one-dimensional chaotic maps. Hence, it becomes easy for an intruder to predict the contents of the message being sent. The proposed work in this paper introduces an improved method for encrypting images, which uses cosine transformation of 3-D Intertwining Logistic Map (ILM). The proposed approach has been split into three major parts. In the first part, Secure Hash Function-256 (SHA-256) is used with cosine transformed ILM (CT-ILM) to generate the chaotic sequence. This chaotic sequence is used by high-efficiency scrambling to reduce the correlations between the adjacent pixels of the image. In the second part, the image is rotated to move all the pixels away from their original position. In the third part, random order substitution is applied to change the value of image pixels. The effectiveness of the proposed method has been tested on a number of standard parameters such as correlation coefficient, Entropy and Unified average change in intensity. The proposed approach has also been tested for decryption parameters like mean square error and peak signal to noise ratio. It can easily be observed from the obtained results that the proposed method of image encryption is more secure and time efficient than some earlier proposed techniques. The approach works for both color and grey scale images.

RELAXATION AND TRANSIENTS IN A TIME-DEPENDENT LOGISTIC MAP

2002 ◽  
Vol 12 (07) ◽  
pp. 1667-1674 ◽  
Author(s):  
EDSON D. LEONEL ◽  
J. KAMPHORST LEAL DA SILVA ◽  
S. OLIFFSON KAMPHORST
Keyword(s):  
Control Parameter ◽  
Logistic Map ◽  
Period Doubling ◽  
Time Dependent ◽  
One Dimensional ◽  
Stability Period ◽  
The One ◽  
Exchange Of Stability ◽  
Small Periodic ◽  
Scaling Arguments

We study the one-dimensional logistic map with control parameter perturbed by a small periodic function. In the pure constant case, scaling arguments are used to obtain the exponents related to the relaxation of the trajectories at the exchange of stability, period-doubling and tangent bifurcations. In particular, we evaluate the exponent z which describes the divergence of the relaxation time τ near a bifurcation by the relation τ ~ | R - Rc |-z. Here, R is the control parameter and Rc is its value at the bifurcation. In the time-dependent case new attractors may appear leading to a different bifurcation diagram. Beside these new attractors, complex attractors also arise and are responsible for transients in many trajectories. We obtain, numerically, the exponents that characterize these transients and the relaxation of the trajectories.

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