Speech Authentication and Recovery Scheme in Encrypted Domain

摘要

This paper proposes a self-embedding fragile watermarking scheme in encrypted speech based on hyper-chaotic system and reference sharing mechanism. Hyper-chaotic system is introduced to hide the feature and improve the confidentiality of original speech. Reference sharing mechanism is used to generate watermark for recovering tampered speech area. Combining the encryption and watermarking technologies, the confidentiality and integrity of original speech can be achieved simultaneously. Analysis and experimental results demonstrate that the proposed algorithm can detect and locate the tampered area. Meanwhile, the self-embedding watermark can be extracted to recover the content of tampered speech with high quality. Additionally, the key space is big enough to resist brute-force attack, while the secure keys are sensitive to slight change.