This research presents,and claries the application of two permutation algorithms,based on chaotic map systems,and applied to a le of speech signals.They are the Arnold cat map-based permutation algorithm,and the Baker...This research presents,and claries the application of two permutation algorithms,based on chaotic map systems,and applied to a le of speech signals.They are the Arnold cat map-based permutation algorithm,and the Baker’s chaotic map-based permutation algorithm.Both algorithms are implemented on the same speech signal sample.Then,both the premier and the encrypted le histograms are documented and plotted.The speech signal amplitude values with time signals of the original le are recorded and plotted against the encrypted and decrypted les.Furthermore,the original le is plotted against the encrypted le,using the spectrogram frequencies of speech signals with the signal duration.These permutation algorithms are used to shufe the positions of the speech les signals’values without any changes,to produce an encrypted speech le.A comparative analysis is introduced by using some of sundry statistical and experimental analyses for the procedures of encryption and decryption,e.g.,the time of both procedures,the encrypted audio signals histogram,the correlation coefcient between specimens in the premier and encrypted signals,a test of the Spectral Distortion(SD),and the Log-Likelihood Ratio(LLR)measures.The outcomes of the different experimental and comparative studies demonstrate that the two permutation algorithms(Baker and Arnold)are sufcient for providing an efcient and reliable voice signal encryption solution.However,the Arnold’s algorithm gives better results in most cases as compared to the results of Baker’s algorithm.展开更多
This paper answers three essential questions for audio speech cryptosystems in time and discrete transform domains.The first question is,what are the best values of sub-keys that must be used to get the best quality a...This paper answers three essential questions for audio speech cryptosystems in time and discrete transform domains.The first question is,what are the best values of sub-keys that must be used to get the best quality and security for the audio cryptosystem in time and discrete transform domains.The second question is the relation between the number of sub-keys,the number of secret keys used,and the audio speech signal block’s size.Finally,how many possible secret keys can be used to get the best quality and security results for the audio speech cryptosystem in time and discrete transform domains.An audio cryptosystem discussed before in recent research is applied to answer the three previous inquiries.Accurate simulation results and analysis answer all three questions;first,there is no specific,well-defined format or rule for sub-key values that must be used to get a better cryptosystem.For the second question,yes,there is a direct relationship between the number of applicable keys,number of available sub-keys,and block size of speech audio signal and formulated into a first-order equation.For the third question,each discrete transform domain has a specific acceptable range of sub-keys that imply a particular number of keys that can be used to get a better cryptosystem.展开更多
The article proposes a new algorithm to improve the security of image encryption based on twodimensional chaotic maps.Chaotic maps are often used in encrypting images.However,the encryption has periodicity,no diffusio...The article proposes a new algorithm to improve the security of image encryption based on twodimensional chaotic maps.Chaotic maps are often used in encrypting images.However,the encryption has periodicity,no diffusion,and at the same time,the real keys space of encryption are fewer than the theoretical keys space,which consequently results in potential security problems.Thus,this article puts forward several ways to solve the problems including adding diffusion mechanism,changing the design of keys and developing a composite encryption system.It designs an algorithm for the version B of the discretized baker map,which is one of the most prevalent chaotic maps,based on which a new image encryption is proposed to avoid the above problems.The simulation results show that the new encryption algorithm is valid and the result can be applied to other two-dimensional chaotic maps,such as the cat map.展开更多
文摘This research presents,and claries the application of two permutation algorithms,based on chaotic map systems,and applied to a le of speech signals.They are the Arnold cat map-based permutation algorithm,and the Baker’s chaotic map-based permutation algorithm.Both algorithms are implemented on the same speech signal sample.Then,both the premier and the encrypted le histograms are documented and plotted.The speech signal amplitude values with time signals of the original le are recorded and plotted against the encrypted and decrypted les.Furthermore,the original le is plotted against the encrypted le,using the spectrogram frequencies of speech signals with the signal duration.These permutation algorithms are used to shufe the positions of the speech les signals’values without any changes,to produce an encrypted speech le.A comparative analysis is introduced by using some of sundry statistical and experimental analyses for the procedures of encryption and decryption,e.g.,the time of both procedures,the encrypted audio signals histogram,the correlation coefcient between specimens in the premier and encrypted signals,a test of the Spectral Distortion(SD),and the Log-Likelihood Ratio(LLR)measures.The outcomes of the different experimental and comparative studies demonstrate that the two permutation algorithms(Baker and Arnold)are sufcient for providing an efcient and reliable voice signal encryption solution.However,the Arnold’s algorithm gives better results in most cases as compared to the results of Baker’s algorithm.
基金This study was funded by the Deanship of Scientific Research,Taif University Researchers Supporting Project Number(TURSP-2020/08),Taif University,Taif,Saudi Arabia.
文摘This paper answers three essential questions for audio speech cryptosystems in time and discrete transform domains.The first question is,what are the best values of sub-keys that must be used to get the best quality and security for the audio cryptosystem in time and discrete transform domains.The second question is the relation between the number of sub-keys,the number of secret keys used,and the audio speech signal block’s size.Finally,how many possible secret keys can be used to get the best quality and security results for the audio speech cryptosystem in time and discrete transform domains.An audio cryptosystem discussed before in recent research is applied to answer the three previous inquiries.Accurate simulation results and analysis answer all three questions;first,there is no specific,well-defined format or rule for sub-key values that must be used to get a better cryptosystem.For the second question,yes,there is a direct relationship between the number of applicable keys,number of available sub-keys,and block size of speech audio signal and formulated into a first-order equation.For the third question,each discrete transform domain has a specific acceptable range of sub-keys that imply a particular number of keys that can be used to get a better cryptosystem.
基金supported by the National Natural Science Foundation of China (Grant No.60474016)the Scientific Research Foundation of Hunan Provincial Education Department (No.08B015).
文摘The article proposes a new algorithm to improve the security of image encryption based on twodimensional chaotic maps.Chaotic maps are often used in encrypting images.However,the encryption has periodicity,no diffusion,and at the same time,the real keys space of encryption are fewer than the theoretical keys space,which consequently results in potential security problems.Thus,this article puts forward several ways to solve the problems including adding diffusion mechanism,changing the design of keys and developing a composite encryption system.It designs an algorithm for the version B of the discretized baker map,which is one of the most prevalent chaotic maps,based on which a new image encryption is proposed to avoid the above problems.The simulation results show that the new encryption algorithm is valid and the result can be applied to other two-dimensional chaotic maps,such as the cat map.
