SNC: A Stem-Native Codec for Efficient Lossless Audio Storage with Adaptive Playback Capabilities

TL;DR

The paper introduces SNC, a new lossless audio format that efficiently compresses stems plus residuals, enabling adaptive playback and remixing with significantly reduced file size and maintained audio quality.

Contribution

SNC is the first lossless format to store stems and residuals separately, allowing for adaptive features without increasing storage requirements.

Findings

38.2% file size reduction compared to FLAC

Perceptually transparent audio quality (STOI=0.996)

Supports context-aware adaptive playback and remixing

Abstract

Current audio formats present a fundamental trade-off between file size and functionality: lossless formats like FLAC preserve quality but lack adaptability, while lossy formats reduce size at the cost of fidelity and offer no stem-level access.We introduce the Stem-Native Codec (SNC), a novel audio container format that stores music as independently encoded stems plus a low-energy mastering residual. By exploiting the lower information entropy of separated stems compared to mixed audio, SNC achieves a 38.2% file size reduction versus FLAC (7.76 MB vs. 12.55 MB for a 2:18 test track) while maintaining perceptual transparency (STOI = 0.996). Unlike existing formats, SNC enables context-aware adaptive playback, spatial audio rendering, and user-controlled remixing without requiring additional storage. Our experimental validation demonstrates that the stems-plus residual architecture successfully decouples the conflicting requirements of compression efficiency and feature richness, offering a practical path toward next-generation audio distribution systems.