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arXiv · 2510.21196

PhoenixCodec: Taming Neural Speech Coding for Extreme Low-Resource Scenarios

Zixiang Wan·Haoran Zhao·Guochang Zhang·Runqiang Han·Jianqiang Wei·Yuexian Zou
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Abstract

This paper presents PhoenixCodec, a comprehensive neural speech coding and decoding framework designed for extremely low-resource conditions. The proposed system integrates an optimized asymmetric frequency-time architecture, a Cyclical Calibration and Refinement (CCR) training strategy, and a noise-invariant fine-tuning procedure. Under stringent constraints - computation below 700 MFLOPs, latency less than 30 ms, and dual-rate support at 1 kbps and 6 kbps - existing methods face a trade-off between efficiency and quality. PhoenixCodec addresses these challenges by alleviating the resource scattering of conventional decoders, employing CCR to enhance optimization stability, and enhancing robustness through noisy-sample fine-tuning. In the LRAC 2025 Challenge Track 1, the proposed system ranked third overall and demonstrated the best performance at 1 kbps in both real-world noise and reverberation and intelligibility in clean tests, confirming its effectiveness.

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Zixiang Wan, Haoran Zhao, Guochang Zhang, Runqiang Han, Jianqiang Wei, Yuexian Zou. 2026-02-23. PhoenixCodec: Taming Neural Speech Coding for Extreme Low-Resource Scenarios. https://arxiv.org/abs/2510.21196

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