RFC 9639 · PROPOSED STANDARD · 2024

Free Lossless Audio Codec

Overview

RFC 9639, “Free Lossless Audio Codec”, is a Proposed Standard document published in December 2024 by M.Q.C. van Beurden, A. Weaver. The canonical text is published by the RFC Editor.

Abstract

This document defines the Free Lossless Audio Codec (FLAC) format and its streamable subset. FLAC is designed to reduce the amount of computer storage space needed to store digital audio signals. It does this losslessly, i.e., it does so without losing information. FLAC is free in the sense that its specification is open and its reference implementation is open source. Compared to other lossless audio coding formats, FLAC is a format with low complexity and can be encoded and decoded with little computing resources. Decoding of FLAC has been implemented independently for many different platforms, and both encoding and decoding can be implemented without needing floating-point arithmetic.

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 9639 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

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