Luvix

Luvix is a CLI toolkit for HDR gain-map images: inspect, split SDR base and gain map, rebuild edited captures, validate, and export flattened HDR TIFFs.

Current release-candidate scope

The tested backend processes Apple HDR gain-map HEIC captures on macOS using ImageIO/Core Image and Swift. It supports inspect, extract, rebuild, validate, inspect-hdr, and export tiff. A 32-bit linear float TIFF with matching source-supported ICC has been validated in Photoshop. The 16-bit PQ TIFF was visually validated with an externally supplied P3 PQ ICC. General JPEG gain-map input, ISO/Ultra HDR interoperability, and arbitrary ICC source profiles are roadmap items, not current supported features.

Install

Recommended for a command-line application:

uv tool install luvix
luvix --version

Alternatively, use pipx install luvix, or install luvix with pip inside an activated virtual environment.

The installed command is luvix. uv run luvix is only for development from a source checkout.

Quick start

luvix doctor
luvix inspect ~/Pictures/photo.HEIC
luvix extract ~/Pictures/photo.HEIC --output ~/Pictures/work/photo
luvix export tiff ~/Pictures/photo.HEIC \
  --bit-depth 32 --transfer linear --color-space source \
  --output ~/Pictures/work/photo_linear32.tif

For 16-bit PQ output, supply a compatible external PQ ICC and an explicit reference white. See the user guide for the full workflow and current support boundaries.

Documentation

• User guide: full command walkthrough, output formats, and troubleshooting.
• Architecture: gain-map model, color handling, and format constraints.
• Roadmap: planned JPEG, ISO 21496-1, Ultra HDR, multichannel maps, and color-space expansion.
• Release checklist: CI, package verification, merge, publish, and install smoke tests.
• Changelog

Development checks

uv run ruff check .
uv run ruff format --check .
uv run pytest -q
uv lock --check
uv build
uv run --locked twine check dist/*

The native Apple backend requires macOS and swiftc. The Python package itself is cross-platform, but this does not imply the Apple HDR features run on Linux.

License

Apache License 2.0. Do not redistribute proprietary reference ICC profiles or private photographs as part of Luvix.