RustyOpus

Pure-Rust Opus for Elixir. No C libopus, no ffmpeg, no external process — shrink real Ogg Opus blobs (or work with raw packets/PCM) in one BEAM process.

Headline: take an Ogg Opus file/blob and make it smaller with a numeric bitrate:

{:ok, smaller} = RustyOpus.reencode(ogg_blob, bitrate: 20_000)

That is the whole call. Useful ladder values match MemoMoo-style profiles: 8_000, 12_000, 16_000, 20_000, 24_000, 32_000.

Quick start

# Ogg Opus blob → smaller Ogg Opus blob (default path for files)
{:ok, smaller} = RustyOpus.reencode(ogg_blob, bitrate: 20_000)

# Raw packets / PCM (no container)
{:ok, packets} = RustyOpus.encode(pcm, 16_000, 1, bitrate: 24_000)
{:ok, pcm}     = RustyOpus.decode(packets, 16_000, 1)

Data contract

Ogg Opus — RFC 7845 binaries (audio/ogg / .ogg) for reencode/2.
PCM — little-endian IEEE-754 f32, interleaved for stereo.
Opus packets — raw binaries (no container).

No WebM/MP4. Never launches an external process. See the codec guide.

Features

RustyOpus.reencode/2 — Ogg Opus blob → lower bitrate Ogg Opus blob (opus-rs + thin Ogg)
RustyOpus.encode/4, decode/4, transcode/5 — whole-stream raw packet/PCM path
RustyOpus.Encoder / Decoder — per-frame control
Dirty-scheduled codec work; panic containment at the NIF boundary
Checksum-verified precompiled NIFs with source-build fallback

Supported OS

Precompiled NIFs are published for:

Apple Silicon macOS (aarch64-apple-darwin)
Intel macOS (x86_64-apple-darwin)
ARM64 Linux glibc (aarch64-unknown-linux-gnu)
ARM64 Linux musl / Alpine (aarch64-unknown-linux-musl)
x86-64 Linux glibc (x86_64-unknown-linux-gnu)
x86-64 Linux musl / Alpine (x86_64-unknown-linux-musl)

Other targets can build from source with RUSTY_OPUS_BUILD=1 and Rust 1.89.0.

Technology

Elixir module	Native crate	Rust packages
`RustyOpus`	`native/rusty_opus_native`	`opus-rs 0.1.29`

Development

bin/qa_check.sh

Committed fixtures include real MemoMoo audio_versions Ogg Opus speech blobs for reencode/2 tests. Tests need neither the live DB nor ffmpeg.

Release

Bump the version in mix.exs and native/rusty_opus_native/Cargo.toml.
Run bin/qa_check.sh and push the green version commit.
Tag v0.3.2; the release workflow builds and smoke-tests every precompiled NIF.
Publish the Hex package and GitHub release (maintainer step).

License

RustyOpus is licensed under the Apache License 2.0. Bundled codec: opus-rs (BSD-3-Clause) — see NOTICE and provenance.