Image encryption using Discrete Parametric Cosine Transform

This paper introduces a new effective image encryption algorithm using the Discrete Parametric Cosine Transform (DPCT). The new algorithm transforms images into the frequency domain using the DPCT with a set of parameters, and then converts images back into the spatial domain using the inverse DPCT with a different set of parameters to obtain the encrypted images. Its security keys are the combination of the parameters of the DPCT and inverse DPCT. The simulation results show that the algorithm can fully or partially encrypt different types of digital images with efficiency while preserving the quality of the images. The algorithm can be used to protect different types of multimedia data. It can be also used for simultaneous data encryption and compression by embedding it in a data compression process such as JPEG.