As synthetic voices become nearly indistinguishable from human speech, no single technique can reliably prevent their misuse. At the Yamagishi Lab, National Institute of Informatics (NII), Japan, we are advancing both passive and proactive defenses as complementary layers of protection. On the passive side, we have extended speech deepfake detection, which decides whether an utterance is synthesized, toward word localization, which identifies the specific words within an utterance that have been manipulated. On the proactive side, we have extended conventional audio watermarking, which embeds imperceptible information to verify the origin of speech, toward self-recovery watermarking, which can also locate tampered segments and partially restore the original content. Finally, I will share some ideas on what the speech community can do together to counter the misuse of speech technologies that is already occurring in the real world.

Junichi Yamagishi received a Ph.D. from the Tokyo Institute of Technology in 2006 for a thesis that pioneered speaker-adaptive speech synthesis. He is a professor at the National Institute of Informatics, Tokyo, Japan. Previously, he held an EPSRC Career Acceleration Fellowship in the Centre for Speech Technology Research (CSTR) at the University of Edinburgh, U.K., from 2011 to 2016. He has authored and co-authored more than 400 refereed papers in international journals and conferences.
He served as an elected member of the IEEE Speech and Language Technical Committee from 2013 to 2019, as an Associate Editor for the IEEE/ACM Transactions on Audio, Speech, and Language Processing from 2014 to 2017, as a chairperson of ISCA SynSIG from 2017 to 2021, as a Senior Associate Editor for the IEEE/ACM Transaction on Audio, Speech and Language Processing from 2019 to 2023, and as a technical committee of the Asia-Pacific Signal and Information Processing Association (APSIPA) Multimedia Security and Forensics from 2018 to 2023. He has been a member of the IEEE Signal Processing Society Education Board since 2021.
He received the Itakura Prize from the Acoustic Society of Japan, the Kiyasu Special Industrial Achievement Award from the Information Processing Society of Japan, the Young Scientists’ Prize from the Minister of Education, Science and Technology, the JSPS prize from the Japan Society for the Promotion of Science, the best paper award at the IEEE International Workshop on Information Forensics and Security (WIFS), the Docmo mobile science award, and IEEE Biometrics Council’s BTAS/IJCB 5-Year Highest Impact Award in 2010, 2013, 2014, 2016, 2017, 2018, and 2023, respectively.