Eliminating the texture features in visually meaningful cipher images

Generally, most image encryption algorithms transform original images into texture-like or noise-like ones. Unfortunately the feature like texture or noise is just a hint of the existence of encryption for attackers. To solve this problem, Bao et al. [Inf. Sci. 324(2015)197-207] proposed a new image encryption algorithm which can transform original images into visually meaningful ones. However, the resulting cipher images have some texture features which may be a hint of the existence of encryption to some extent. To overcome this flaw, we present a new visually meaningful image encryption algorithm based on discrete wavelet transform and discrete quantum walks. Numerical simulation, security analysis and performance comparison demonstrate that our proposal is superior to Bao et al.’s scheme. It promotes the combination of image encryption and quantum computation.