activity
20242026
collaborators

30 papers

cs.SD2026

Online Algorithms for Independent Low-Rank Matrix Analysis and Rank-Constrained Spatial Covariance Matrix Estimation Based on Maximum Weighted Likelihood Estimation

Yuto Ishikawa, Norihiro Takamune, Tomohiko Nakamura +4

Real-time multichannel speech extraction (MSE) under diffuse noise conditions is an important task with a wide range of applications, such as speech recognition and hearing aids. I…

cs.SD2026

Differentiable Digital Signal Processing Mixture Model-Guided Diffusion for Synthesis Parameter Estimation from Harmonic Sound Mixtures

Kengo Takemoto, Tomohiko Nakamura, Hiroshi Saruwatari

A differentiable digital signal processing (DDSP) autoencoder reconstructs a monophonic harmonic sound through three types of synthesis parameters: fundamental frequency, loudness,…

cs.SD2026

Lead Vocal Separation from Vocal Ensemble Mixtures Using Phoneme Alignment

Yuma Narahata, Tomohiko Nakamura, Yuki Saito +1

Contemporary a cappella singing often has a lead-and-accompaniment texture, where the lead vocal (Vo) part carries the main melody and the remaining vocal parts provide accompanime…

cs.CL2026

Language-Statistical Analysis of Neural Audio Codec Tokens Across Architectures, Corpora, and Noise Conditions

Joonyong Park, Shinnosuke Takamichi, David M. Chan +3

Neural audio codecs (NACs) convert speech into discrete token sequences, and prior work has reported that these sequences follow language-like statistical laws. This paper analyzes…

cs.SD2026

Auditing Protocol-Level Shortcuts in Large Audio Language Model Judges for Speech Evaluation

Joonyong Park, David M. Chan, Yuki Saito +1

Large audio-language models (LALMs) are increasingly used as automatic judges for speech evaluation. However, high agreement with human ratings does not guarantee that their verdic…

cs.CL2026

DuplexChat: Constructing Speaker-Separated Full-Duplex Dialogue Speech at Scale for Spoken Dialogue Language Modeling

Wataru Nakata, Yuki Saito, Hiroshi Saruwatari

Full-duplex spoken dialogue models are trained on conversational speech in which each speaker is represented as a separate stream, but existing large-scale public speech corpora ar…

eess.AS2026

CraBERT: Efficient Phoneme Encoder Pre-Training via Cascade Fusion of Subword Representations for Text-to-Speech

Dong Yang, Yuki Saito, Wataru Nakata +1

This paper introduces CraBERT, a pre-trained phoneme encoder (PPEnc) designed for efficient pre-training in text-to-speech (TTS). CraBERT employs a cascade-fusion architecture and…

eess.AS2026

Fast Multichannel NMF with Block-Diagonal Spatial Covariance Matrices for Efficient Blind Source Separation Using Distributed Microphone Arrays

Hirotaka Nishikori, Nobutaka Ito, Kouei Yamaoka +2

Distributed microphone arrays composed of multiple subarrays enable blind source separation over a wide spatial area. Directly applying fast multichannel nonnegative matrix factori…

eess.AS2026

Kinetic-Optimal Scheduling with Moment Correction for Metric-Induced Discrete Flow Matching in Zero-Shot Text-to-Speech

Dong Yang, Yiyi Cai, Haoyu Zhang +2

Metric-induced discrete flow matching (MI-DFM) exploits token-latent geometry for discrete generation, but its practical use is limited by two issues: heuristic schedulers requirin…

cs.SD2026

DialogueSidon: Recovering Full-Duplex Dialogue Tracks from In-the-Wild Dialogue Audio

Wataru Nakata, Yuki Saito, Kazuki Yamauchi +2

Full-duplex dialogue audio, in which each speaker is recorded on a separate track, is an important resource for spoken dialogue research, but is difficult to collect at scale. Most…

cs.SD2026

Geneses: Unified Generative Speech Enhancement and Separation

Kohei Asai, Wataru Nakata, Yuki Saito +1

Real-world audio recordings often contain multiple speakers and various degradations, which limit both the quantity and quality of speech data available for building state-of-the-a…

cs.SD2026

Dissecting Performance Degradation in Audio Source Separation under Sampling Frequency Mismatch

Kanami Imamura, Tomohiko Nakamura, Kohei Yatabe +1

Audio processing methods based on deep neural networks are typically trained at a single sampling frequency (SF). To handle untrained SFs, signal resampling is commonly employed, b…

cs.SD2026

DistilMOS: Layer-Wise Self-Distillation For Self-Supervised Learning Model-Based MOS Prediction

Jianing Yang, Wataru Nakata, Yuki Saito +1

With the advancement of self-supervised learning (SSL), fine-tuning pretrained SSL models for mean opinion score (MOS) prediction has achieved state-of-the-art performance. However…

cs.SD2025

Emotional Text-To-Speech Based on Mutual-Information-Guided Emotion-Timbre Disentanglement

Jianing Yang, Sheng Li, Takahiro Shinozaki +2

Current emotional Text-To-Speech (TTS) and style transfer methods rely on reference encoders to control global style or emotion vectors, but do not capture nuanced acoustic details…

cs.SD2025

Drum-to-Vocal Percussion Sound Conversion and Its Evaluation Methodology

Rinka Nobukawa, Makito Kitamura, Tomohiko Nakamura +2

This paper defines the novel task of drum-to-vocal percussion (VP) sound conversion. VP imitates percussion instruments through human vocalization and is frequently employed in con…

cs.SD2025

Spatial-CLAP: Learning Spatially-Aware audio--text Embeddings for Multi-Source Conditions

Kentaro Seki, Yuki Okamoto, Kouei Yamaoka +3

Contrastive language--audio pretraining (CLAP) has achieved remarkable success as an audio--text embedding framework, but existing approaches are limited to monaural or single-sour…

cs.SD2025

Sidon: Fast and Robust Open-Source Multilingual Speech Restoration for Large-scale Dataset Cleansing

Wataru Nakata, Yuki Saito, Yota Ueda +1

Large-scale text-to-speech (TTS) systems are limited by the scarcity of clean, multilingual recordings. We introduce Sidon, a fast, open-source speech restoration model that conver…

cs.CL2025

Analysing the Language of Neural Audio Codecs

Joonyong Park, Shinnosuke Takamichi, David M. Chan +3

This study presents a comparative analysis of the statistical and linguistic properties of neural audio codecs (NACs). We investigate discrete speech tokens produced by various NAC…

eess.AS2025

Speaker-Conditioned Phrase Break Prediction for Text-to-Speech with Phoneme-Level Pre-trained Language Model

Dong Yang, Yuki Saito, Takaaki Saeki +4

This paper advances phrase break prediction (also known as phrasing) in multi-speaker text-to-speech (TTS) systems. We integrate speaker-specific features by leveraging speaker emb…

cs.SD2025

Multi-Sampling-Frequency Naturalness MOS Prediction Using Self-Supervised Learning Model with Sampling-Frequency-Independent Layer

Go Nishikawa, Wataru Nakata, Yuki Saito +3

We introduce our submission to the AudioMOS Challenge (AMC) 2025 Track 3: mean opinion score (MOS) prediction for speech with multiple sampling frequencies (SFs). Our submitted mod…

cs.SD2025

Hyperbolic Embeddings for Order-Aware Classification of Audio Effect Chains

Aogu Wada, Tomohiko Nakamura, Hiroshi Saruwatari

Audio effects (AFXs) are essential tools in music production, frequently applied in chains to shape timbre and dynamics. The order of AFXs in a chain plays a crucial role in determ…

cs.SD2025

Active Learning for Text-to-Speech Synthesis with Informative Sample Collection

Kentaro Seki, Shinnosuke Takamichi, Takaaki Saeki +1

The construction of high-quality datasets is a cornerstone of modern text-to-speech (TTS) systems. However, the increasing scale of available data poses significant challenges, inc…

cs.SD2025

RELATE: Subjective evaluation dataset for automatic evaluation of relevance between text and audio

Yusuke Kanamori, Yuki Okamoto, Taisei Takano +3

In text-to-audio (TTA) research, the relevance between input text and output audio is an important evaluation aspect. Traditionally, it has been evaluated from both subjective and…

cs.SD2025

Local Equivariance Error-Based Metrics for Evaluating Sampling-Frequency-Independent Property of Neural Network

Kanami Imamura, Tomohiko Nakamura, Norihiro Takamune +2

Audio signal processing methods based on deep neural networks (DNNs) are typically trained only at a single sampling frequency (SF) and therefore require signal resampling to handl…