lightcraft/crates/gpu
Harald Hoyer 987d14b6ad LR-PROF-CAMERACOLOR: ARW camera looks bleach highlights and shift hue by brightness
A sunny ILCE-7M4 waterfall shot rendered yellow: sunlit rock came out
cream, +4 b* in the brightest fifth of the picture. Camera JPEGs make
shadows up to 1.4x more colourful and bleach highlights to 0.1-0.3x
(a per-channel tone curve), which a luminance-only curve can't do.

- CameraTone gains an 8-node chroma-by-display-luminance curve, fitted
  per file (bright pixels included) and kept only when it lowers the
  held-out error; applied after the tone map on CPU and GPU, keeping
  luminance. Old smart-preview headers load with an identity curve.
- The hue/saturation table gets an sRGB-encoded value axis: dark yellows
  had to turn toward orange while bright yellow-greens turned toward
  green. It is applied after the baseline exposure, as it is fitted.
- Matrix-only and matrix+table looks are completed (tone, chroma) and
  compared in gamma-encoded values; acceptance gates stay linear.

29 local ARWs vs their camera JPEGs: mean dE 4.23 -> 3.54, every file
closer, saturated areas 7.65 -> 6.41. Render cache v10.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-10-07 11:04:39 +02:00
..
src LR-PROF-CAMERACOLOR: ARW camera looks bleach highlights and shift hue by brightness 2026-10-07 11:04:39 +02:00
tests LR-PROF-CAMERACOLOR: ARW camera looks bleach highlights and shift hue by brightness 2026-10-07 11:04:39 +02:00
Cargo.toml M5.2a: lightcraft-gpu crate (wgpu compute) with the per-pixel stage on the GPU 2026-10-01 02:29:54 -04:00