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arXiv · 2611.00732

8 Bits to End the Loudness War: Lossless Floating-Point Compression for Audio Streams

Ali Heydari
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Abstract

We present a native extension to the Free Lossless Audio Codec (FLAC) providing lossless compression for IEEE 754 single-precision (binary32) floating-point audio, alongside a survey and empirical benchmark of existing floating-point compression methods. While professional recording hardware increasingly adopts 32-bit float converters and digital audio workstations process sound exclusively in floating-point math, consumer distribution remains constrained to fixed-point integer PCM. Through Dynamic Positional Alignment (DPA), our implementation achieves approximately 44.1% compression ratios on natural multi-stage ADC recordings--matching the storage footprint of standard 24-bit integer FLAC--and approximately 60.2% on complex digital workstation masters. By preserving dynamic peaks beyond 0 dBFS, the format also allows listeners to undo clipping, providing a practical technical path away from the loudness war with virtually no storage overhead. We do not claim to introduce a fundamentally new compression paradigm; our approach is conceptually similar to the floating-point mechanism in WavPack (which remains undocumented in published literature). Instead, this paper compares existing methods, provides theoretical grounding for why they succeed or fail, benchmarks current codec implementations, and contributes a reference implementation of a proven method within the FLAC ecosystem.

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Ali Heydari. 2026-10-31. 8 Bits to End the Loudness War: Lossless Floating-Point Compression for Audio Streams. https://arxiv.org/abs/2611.00732

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