oximg

High-performance image compression in Rust: a library, a CLI, and a self-hostable HTTP server. Currently a JPEG resize/compression PoC.

Pipeline

JPEG bytes
  → mozjpeg decode with DCT shrink-on-load (kept ≥ 1.7x target size)
  → linear-light resize: sRGB u8 → linear u16 → Lanczos3 (SIMD) → sRGB u8
  → mozjpeg encode (fast preset; PRESET=small = trellis + progressive)

Concurrent identical requests are coalesced and share one result. CPU concurrency is pinned to the core count with a semaphore; the HTTP layer (axum/tokio) only does queueing and IO.

Benchmarks

BENCH.md — throughput, latency, and memory vs imgproxy and imagor, on macOS and Linux x86_64.
bench/quality/QUALITY.md — output quality (SSIMULACRA2) at matched settings vs imgproxy and sharp.

Usage

cargo build --release
IMAGES_DIR=./images PORT=8081 QUALITY=80 ./target/release/oximg
curl "localhost:8081/resize/500/500/photo.jpg" -o out.jpg

Or with Docker:

docker build -t oximg .
docker run -p 8081:8081 -v $PWD/images:/images:ro oximg

Environment variables: PORT (8081), IMAGES_DIR (./images), QUALITY (80), PRESET=small (mozjpeg trellis+progressive), OXIMG_RESIZE=srgb (resize in sRGB space instead of linear light), OXIMG_DCT_MARGIN (1.7), OXIMG_PAR (resize threads, 1).

Not yet implemented (out of PoC scope)

WebP / AVIF / JXL output and content negotiation
EXIF orientation / ICC profile handling
Remote sources (S3 / HTTP), URL signing, caching
Production-grade load testing

Status

Experimental PoC — APIs and the HTTP interface will change without notice. The oximg crates.io / @oximg npm packages are name reservations for now.

License

Apache-2.0