A novel scheme for simultaneous image compression and encryption based on wavelet packet transform and multi-chaotic systems

摘要

This paper presents a new scheme for simultaneous image compression and encryption. First, the approach of wavelet packet transform is used to decompose an image. Herein, the image is divided into four different types and self-adaptive approaches are designed to process the four signals. Second, a fleeting image encryption algorithm based on multi-chaotic systems is proposed to protect the security of the image. The above method not only balances the compression ratio and reconstruction quality, but also greatly improves the encryption speed and transmission security of the image. More importantly, the proposed scheme solves a long-standing contradiction that a signal should be first compressed or encrypted, which often appears in traditional image compression and encryption systems. Computer simulations and numerical analysis validate that the proposed scheme possesses superior security, high efficiency and promising practical value for images encryption and transmission.