post op• Data kinds: none → lut (an op determined by its arguments alone — it takes no image or data input)
• Call: import fullseye as fs; fs.ledger.color_lut(size=17, gain=(1.0, 1.0, 1.0), lift=(0.0, 0.0, 0.0), gamma=(1.0, 1.0, 1.0), saturation=1.0) (to call the implementation directly, import gfx2d; gfx2d.color_lut(size=17, gain=(1.0, 1.0, 1.0), lift=(0.0, 0.0, 0.0), gamma=(1.0, 1.0, 1.0), saturation=1.0); from the registry, opsgfx2d.get("color_lut"))
• GPU: none (CPU reference implementation only)
Build a 3-D colour LUT, (n, n, n, 3) indexed [r, g, b].
out = lift + gain * in**gamma per channel, then saturation is applied about the Rec. 709 luma and the result is clipped once. With all defaults this is the identity LUT, and because trilinear interpolation is exact for a function that is linear in each variable, color_grade with the identity LUT is the identity to float64 rounding (measured maximum 3.3e-16 at size 17 and 2.2e-16 at size 2) — the property the suite uses to prove the interpolation itself is right before testing any grade.
• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).
• Operator provenance and references — the sources of the research/methods this op family came from.
• The canonical algorithm (author, year) and its uses are named in the family usage guide above.
• genspark_external_review — py -3.11 examples/genspark_external_review.py
• gfx2d_scene — py -3.11 examples/gfx2d_scene.py
lut as input)post)bloom · vignette · chromatic_aberration · film_grain · color_grade · dither · palette_quantize
*Provenance: gfx2d.py — GFX2D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.