Privacy Protection for Speech Information

Ubiquitous network society will be achieved soon. In the society, all electronic equipments including "sensors" are connected to the network and communicate each other to share information. Sensor information is very important for the network, especially for virtual reality systems which give feeling of begin there. Since the sensor information, however, includes a lot of privacy information, it is not preferred to send raw privacy information through the network. In this paper, we describe about privacy protection for speech information. We think that the privacy information in speech is "voice characteristics" and "linguistic privacy information." We try to protect these privacy information by using "voice conversion" and "deletion of privacy linguistic information for speech recognition result." Since, however, speech recognition technology is not robust in real environment still now, "elimination of only speech in noisy speech" technique is also considered.