Interspeech 2026 · Audio samples

Acoustic token admixture for joint speaker and content anonymization

Ali Golmakani, Seyed Ahmad Hosseini, Omar Manil Bendali, Emmanuel Vincent, Brij Mohan Lal Srivastava

Our system hides two things in a recording: who is speaking (biometric identity) and what identifies them (named entities). It works on a single stream of RVQ-Whisper acoustic tokens. Encoder-derived tokens and phoneme-conditioned tokens are mixed frame by frame, with mixing ratio β and a cosine-similarity gate τ = 0.6. When NER flags a sensitive span, the system regenerates only those frames and leaves the surrounding prosody untouched. On VoicePrivacy 2024 it reaches EER 42.54% with WER 3.73% at β = 0.7.

All anonymized outputs below are 16 kHz BigVGAN vocoder outputs. Use headphones for the fairest comparison.

Anonymization and speaker consistency

Each utterance is anonymized with four pseudospeakers, each fixed by a random seed (spk1 to spk4 are seeds 3358, 4930, 5192 and 5978). Listen down a column to hear one pseudospeaker stay consistent across different content. Listen along a row to hear the same content rendered by different pseudospeakers.

β = 0.7

Columns: Original · spk1 · spk2 · spk3 · spk4

Input 1

Original
spk1
spk2
spk3
spk4

Input 2

Original
spk1
spk2
spk3
spk4

Input 3

Original
spk1
spk2
spk3
spk4

Input 4

Original
spk1
spk2
spk3
spk4

Speech editing

NER-triggered content replacement (paper, Sec. 2.3). orig is the source recording and anon is the anonymized version with unchanged content. v1 and v2 replace the detected entity with a different name or place. Only the frames of the entity span are regenerated. They are spliced back with an 8-frame (about 160 ms) crossfade, so the pseudospeaker and the surrounding prosody stay intact.

β = 0.7 · NER span replacement

Sample 1

“The American planes maneuvered in such a way as to encircle the Taube.”

  • v1: American → Australian
  • v2: American → English
orig
anon
v1
v2

Sample 2

“As they sat down, a burst of applause drew Alexander's attention to the stage.”

  • v1: Alexander → William
  • v2: Alexander → Jonathan
orig
anon
v1
v2

Sample 3

“The power and enterprise of Spain were directed to wider and richer fields.”

  • v1: Spain → France
  • v2: Spain → Germany
orig
anon
v1
v2

Sample 4

“However, Jaime Alguersuari failed to score any points in the season.”

  • v1: Jaime Alguersuari → David Jones
  • v2: Jaime Alguersuari → Victor Smith
orig
anon
v1
v2

Admixture effect

The same utterance anonymized at β = 0.0, 0.7 and 1.0. β is the probability that a frame uses a phoneme-derived token instead of the encoder-derived token. At β = 0.0 the only change is the pseudospeaker substitution, so more of the source speaking style survives. Higher β removes more residual speaker cues from the token stream. On VoicePrivacy 2024, EER rises from 23.0% at β = 0.0 to 42.54% at β = 0.7. β = 1.0 is included to hear the fully phoneme-derived end of the range; the paper does not report it.

Sample 1

orig
β = 0.0
β = 0.7
β = 1.0

Sample 2

orig
β = 0.0
β = 0.7
β = 1.0

Sample 3

orig
β = 0.0
β = 0.7
β = 1.0

Sample 4

orig
β = 0.0
β = 0.7
β = 1.0