Research On Data Hiding In Encrypted Images Based On Compressive Sensing

With the advent of the big data era,how to provide security for massive data in Cloud or Internet of Things is essential for the practical application of these technologies.Compressive sensing(CS)is a novel sampling technique which can encrypt and compress data during the process of sample.Since CS can break the limits of Nyquist-Shannon sampling theorem,compress data greatly and recover the original data accurately,it becomes the focus in many areas.Meanwhile,data hiding technology is a complementary tool for traditional Cryptography,and it has developed rapidly because it can provide covert communication,information protection,copyright protection and so on.Therefore,it has important research value to combine CS and data hiding,and deeply study the data hiding in encrypted images.The main work of this thesis consists of three aspects:1)Through the systematical study on data hiding,CS and the existing data hiding schemes based on CS,we have investigated the potential new breakthrough.2)A high capacity data hiding scheme in encrypted image based on CS for nonequivalent resources is proposed.In order to improve the reconstructed image quality,the cover image is segmented for further processing by introducing the prediction error technique.The experimental results show that the scheme not only improves the quality of the restored image,but also improves the embedding rate.Meanwhile,since CS has a low computation cost in the sensing part while the recovery computation is rather complex at the receiving end,the proposed scheme is suitable for nonequivalent resources.Besides,the proposed scheme is a separable data hiding scheme.3)A secure digital watermarking scheme for encrypted image based on sparse representation is proposed.In this scheme,the watermark is embedded in the sparse representation of the cover data,and the verification operation is calculated with the fuzzy watermark and the encrypted watermarked data.The proposed scheme not only provides security for watermark,but also ensures the security of the entire verification process,so it is suitable for Cloud verification system.The experimental results show that the proposed scheme can correctly verify the watermark while protecting the data security.Besides,the watermarking scheme has good performance on invisibility and robustness.