Meslek Yüksekokulları
http://hdl.handle.net/20.500.12397/13474
2021-04-12T00:14:23ZHigher Dimensional Chaotic Linear Transformations of Colored Image Encryptions
http://hdl.handle.net/20.500.12397/13849
Higher Dimensional Chaotic Linear Transformations of Colored Image Encryptions
Elmacı, Deniz; Baş Çatak, Nurşin
In this study, a well-known chaotic transformation namely Arnold’s CAT map is used to extend 2-dimensional mapping to a higher dimension. This extension is achieved by means of the planar extension and Multinacci series. The demonstration of a 3-dimensional Arnold’s CAT map is performed by RGB component substitution of a colored image. For this purpose, the colored image is converted from a standard RGB space into an intensity-hue-saturation (IHS) space. Consequently, both Chebyshev and Hadamard map is employed for encryption of the intensity component. Besides, CAT map is engaged to encrypt the hue and saturation components. According to the results, the proposed method has a great potential to be an efficient tool for data encryption.
2019-05-08T00:00:00ZAn Efficient Image Encryption Algorithm for the Period of Arnold's CAT Map
http://hdl.handle.net/20.500.12397/13848
An Efficient Image Encryption Algorithm for the Period of Arnold's CAT Map
Elmacı, Deniz; Baş Çatak, Nurşin
Arnold's CAT Map (ACM) is a chaotic transformation of the 2-dimensional toral automorphism T^2 defined by the mapping Γ ∶ T^2 → T^2. There are many applications of ACM in various research areas such as: steganography, encryption of images, texts and
watermarks. The transformation of an image is achieved by the randomized order of pixels. After a finite number of repetitions of the transformation, the original image reappears. In this study, encryption of two images is demonstrated together with a proposed algorithm.
Moreover, the periodicity of ACM is discussed and an algorithm to change the period of ACM is suggested. The resultant period obtained from the new algorithm is compared with the period obtained from the usual ACM. The results show that the period of the proposed
algorithm grows exponentially while the period of ACM has an upper bound.
2018-03-30T00:00:00Z