AVELUNE

Project status

Implemented scope, interpretation, and known limitations.

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Avelune is experimental. Nothing is frozen.

The software release line is 0.x. ALV1 and ALA1 identify Draft Generation 1 bitstreams; the 1 is a generation label, not a compatibility promise. Incompatible specification, container, codec, and API changes are allowed while the draft is under active development.

Implemented POC

  • custom ALV1 lossy/lossless 8-bit 4:2:0 video;
  • custom ALA1 lossy/lossless audio;
  • bounded immutable video dependencies, half-sample motion, palette blocks, integer WHT residuals, and static rANS entropy coding;
  • front-indexed CRC-protected container with independently addressable epochs;
  • one canonical safe Rust implementation with per-stream state and explicit input finalization;
  • a separate audited SIMD/unsafe kernel crate;
  • one independent scalar conformance oracle for differential testing;
  • native CLI with FFmpeg-based ordinary-media input/output;
  • scalar and SIMD128 WASM decoding plus batch and streaming browser A/V encoder APIs;
  • browser HTTP Range and local-file playback with cancellable decode generations;
  • browser conversion of FFmpeg-readable media to .avl, with bounded raw video/PCM sinks and incremental Avelune epoch output;
  • OPFS spooling of completed compressed epochs when supported, with an in-memory compressed-output fallback;
  • Canvas2D and WebGPU YUV presentation;
  • property, hostile-input, mutation, differential, benchmark, and format-research tooling.

Implementation model

Applications use crates/avelune. crates/avelune-reference is an independently implemented oracle for conformance and differential tests, not an application backend. Unsafe/intrinsic code is isolated in crates/avelune-kernels.

Keeping the oracle independent makes differential agreement meaningful without maintaining a second application stack.

Known limitations

  • general-video rate/distortion is behind mature x264/x265/VP9/AV1 encoders on tested material;
  • lossy ALA1 needs substantially more codec research and perceptual tuning;
  • Draft Generation 1 supports only the current baseline video/audio profiles;
  • avelune play is a convenience FFmpeg/ffplay path, not the browser-style indexed player;
  • the browser's embedded FFmpeg importer is single-threaded, and browsers without OPFS retain completed compressed output chunks in memory until final assembly;
  • WebGPU compute kernels are experimental; WebGPU presentation is separate from codec semantics;
  • mutation/property testing does not replace sustained coverage-guided fuzzing;
  • no professional security audit or patent-freedom/legal-clearance claim exists.

See docs/development/REFERENCE_ORACLE.adoc and docs/development/VERSIONING.adoc.