arXiv Computation and Language By Dongseong Hwang, Prasanth Yadla, Kaan Elgin, Shifas Padinjaru Veettil, Sivanand Achanta, Dipjyoti Paul, Ramya Rasipuram, Tyler Johnson, Emad Soroush, Chung-Cheng Chiu, Zhifeng Chen

Memory Efficient Audio Synthesis with Decoupled Temporal Depth Diffusion Transformers

Read the original on arXiv Computation and Language →

The paper introduces a memory‑efficient audio synthesis architecture used in Siri Expressive Voices, converting semantic audio tokens into high‑fidelity audio via a residual vector quantization (RVQ) pipeline that decouples temporal and depth processing. A single Diffusion Transformer‑style depth decoder generates all RVQ levels autoregressively, while causal sliding‑window attention with fixed‑window key‑value caching keeps memory usage constant regardless of sequence length. Deployed on Apple’s AMX, the system achieves real‑time performance (≈10 ms per step) with only 21 MB peak runtime memory and 329 MB of on‑device assets, enabling continuous streaming of 20–320 s of audio and improving Mean Opinion Scores by +0.28 overall and +0.42 on conversational speech compared to the previous on‑device TTS system.

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv Computation and Language.

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