oxideav-qoi

Pure-Rust QOI (Quite OK Image) reader and writer for the oxideav framework. Clean-room implementation of the one-page specification published at qoiformat.org.

Format coverage

QOI is a small, lossless RGB(A) image format invented by Dominic Szablewski. The whole specification fits on one printed page; this crate covers all of it:

Encoder always picks the smallest legal chunk for each pixel using the priority order set out in the spec (RUN > INDEX > DIFF > LUMA > RGB / RGBA), so output sizes match the reference encoder byte-for-byte on files we have access to.

API

use oxideav_qoi::{parse_qoi, encode_qoi, QoiImage, QoiChannels};

// Decode a complete QOI file.
let img: QoiImage = parse_qoi(&qoi_bytes)?;
assert!(matches!(img.channels, QoiChannels::Rgba | QoiChannels::Rgb));

// Re-encode (round-trip).
let bytes: Vec<u8> = encode_qoi(
    img.width,
    img.height,
    img.channels as u8,           // 3 or 4
    &img.pixels,                  // tightly packed RGB or RGBA
);

QoiImage carries width, height, channels, colorspace, and a flat pixels: Vec<u8> (RGB or RGBA, no row padding). The encoder takes plain (w, h, channels, &[u8]) so callers don't need to construct an QoiImage first.

Standalone vs registry-integrated

The crate's default registry Cargo feature pulls in oxideav-core and exposes the framework Decoder / Encoder trait surface plus a registry::register entry point. The sibling registry::register_containers call wires the .qoi file extension into a ContainerRegistry so cli-convert / pipeline output probing can resolve .qoi paths through the central registry instead of a hard-coded list. Disable the feature (default-features = false) for an oxideav-core-free build that still exposes the standalone parse_qoi / encode_qoi API plus crate-local QoiImage / QoiChannels / QoiColorspace / QoiError types.

License

MIT — see LICENSE.