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"))
Build a 3-D colour LUT, (n, n, n, 3) indexed [r, g, b].
out = clip(lift + gain * in**gamma) per channel, then saturation is applied about the Rec. 709 luma. 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.