How ByteDance’s AI‑Powered Audio Signal Processing Elevates Voice, VR, and VoIP

Audio Signal Processing Development Trends

The author, a ByteDance speech signal processing algorithm engineer, divides audio signal processing into three layers: basic algorithms (adaptive filters, array signal processing, psychoacoustics, deep learning), key technology components built on these algorithms (echo cancellation, source localization, beamforming), and high‑quality audio applications such as sound‑field reconstruction, human‑machine interaction, and audio‑video processing.

Historical milestones include Bell Labs' 1979 DSP chip, the rise of microphone arrays in the 1990s, full‑duplex audio processing in video‑conferencing, and recent 3D audio for AR/VR. The field is shifting from traditional DSP to deep‑learning‑based multimodal audio processing.

Intelligent Audio Signal Processing in High‑Quality Audio Capture

Three main scenarios are audio‑video creation, live streaming, and VoIP. All require hardware capable of high‑quality recording. Algorithmic needs include echo cancellation, audio scaling, noise reduction, gain control, and equalization. The focus is moving toward multimodal audio scaling, which combines source information with video scene analysis.

Multimodal audio scaling leverages deep‑learning‑based speech enhancement and model‑based beamforming to extract high‑quality audio from video, followed by post‑processing such as gain synchronization and multi‑source volume balancing.

High‑Quality, Low‑Latency VoIP

System stability through hardware state detection and real‑time audio switching.

Audio quality improvements via reverberation suppression, noise cancellation, and gain control.

Sound beautification using dynamic EQ and vocal enhancement.

Sound‑Field Reconstruction Practice

Sound‑field reconstruction creates 3D audio effects, currently implemented as stereo for online content. Applications include enhancing existing videos, AR/VR experiences, and multi‑speaker podcasts. The process involves sound‑field analysis (determining source positions and paths) and sound‑source extraction using segmentation, beamforming, and multimodal speech enhancement.

Examples show original versus reconstructed videos, demonstrating better alignment of audio source movement with visual cues.

Intelligent Voice Interaction

Key technologies for smart voice interaction include echo cancellation, reverberation suppression, source localization, beamforming, gain control, and EQ. These support full‑chain voice interaction for smart speakers, education hardware, smart home, and wearables.

Future Outlook

ByteDance plans to integrate audio signal processing into smart modules for portable and wearable IoT devices, expand multimodal novel narration with spatial audio, and apply the technology to VR/AR and intelligent audio creation.