linear_trans_color — 2D color op

Data kinds: colorcolor

Call: fullseye.apply(img, "linear_trans_color", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

HALCON equivalent: linear_trans_color (the HALCON reference is a useful guide to its meaning and parameters)

Usage

Linearly transforms between channels using a 3x3 mixing matrix (affine color transform). Corresponds to HALCON's `linear_trans_color` (computes an affine transform of color values for a multichannel image) (this implementation is a pure linear transform with no offset term).

> The detailed description below is the original text — the summary and the headings are translated.

対角成分 0.6 + 非対角 0.2 を基本形とし、a で位相 `theta = pi * a` を

振って対角成分の一部を `cos(theta)/sin(theta)` で回転的に変化させた

行列を作り、各行を合計 1 に正規化してから `c @ M.T` を掛ける。

a が 0→1 で R/G 寄りの重みづけが周期的に入れ替わる。b は未使用。

Detailed usage guide

gallery2d_color_artistic family guide

Background guides (the physics and conventions behind this op)

colorimetry — 測色と分光の知識 — 色は「分光 × 光源 × 観測者」でしか決まらない

References (sample data, literature)

• 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.

Runnable examples (verified samples that actually call this op)

gallery2d_color_artisticpy -3.11 examples/gallery2d_color_artistic.py

Ops the type connects to (they accept color as input)

identity · trans_from_rgb · trans_to_rgb · principal_comp · rgb1_to_gray · rgb3_to_gray · access_channel · edges_color

Same category (color)

cfa_to_rgb · trans_from_rgb · trans_to_rgb · principal_comp · rgb1_to_gray · rgb3_to_gray · access_channel


*Provenance: ops.py — 2D 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.