Hyper chaos followed by DCT and gyrator transform for image encryption

Abstract

Color images can be encrypted using a hyperchaotic system in the Discrete Cosine Transform (DCT) and gyrator transform domains. These encryption techniques provide an added layer of security to protect sensitive image data from unauthorized access or tampering. The Red, Green, And Blue (RGB) components of the original color image are encoded into two-dimensional streams, respectively. These two-dimensional streams, representing the RGB components, are then processed by the display or printing device to recreate the full-color image. This paper proposes a new image encryption scheme that integrates DCT and the gyrator transform simultaneously. This innovative approach enhances the security and robustness of image encryption, making it suitable for a wide range of applications in data protection and transmission. Specifically, four chaotic sequences generated by a hyperchaotic system are blended into streams to synthesize complex sequences. Subsequently, the two-dimensional complex streams are scrambled using the discrete cosine transform and encoded back into an image format. Finally, the parameters in the hyperchaotic system using DCT and the gyrator transform improve the security of the proposed scheme. Theoretical and experimental analyses both confirm the security and validity of the proposed work.