- 著者
-
Zhi Zhu
Katsuhiko Yamamoto
Masashi Unoki
Naofumi Aoki
- 出版者
- 信号処理学会
- 雑誌
- Journal of Signal Processing (ISSN:13426230)
- 巻号頁・発行日
- vol.18, no.6, pp.303-307, 2014-11-25 (Released:2014-11-25)
- 参考文献数
- 7
Speech scrambling aims to eliminate intelligibility of original speech in order to preventing eavesdropping and copyright infringement. There is, however, a problem in that completely recovering scrambled speech into the original speech cannot be achieved with conventional methods. In this paper, we propose a speech scrambling method that uses the random-bit-shift of quantization bits with common keys. We evaluated the confidentiality and efficiency of the proposed method by using two objective measures, SER and PESQ. As a result we confirmed that speech signals can be scrambled into completely unintelligible sounds with the proposed method. Moreover, it is possible to restore a scrambled speech signal into the original one completely. In addition, we also confirmed that the scrambled speech signal could not be descrambled correctly with the wrong key.