cfa_to_rgb — 2D color op

Data kinds: imagecolor

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

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

Usage

Demosaicing from a Bayer pattern (CFA: Color Filter Array) to an RGB image. Approximates HALCON's `cfa_to_rgb` (converts a single-chip color filter array image to an RGB image).

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

単一チャンネルのグレースケール画像を Bayer パターンの生データとみなし、

OpenCV の `cv2.cvtColor` でデモザイクして 3 チャンネル RGB に復元する。

image から color への橋渡し op(進化がカラー系統に入る唯一の入口)。

a は Bayer パターンの並び順を 4 通り(BG/GB/RG/GR の並び)から選ぶ

(`min(3, int(a * 4))` で 0〜3 に量子化)。b は未使用。

パターンが実際の入力と合わない場合、色ズレ・モアレが出る(本来の Bayer

配置が分からない合成画像に対してはどれも「それらしい」RGB化でしかない)。

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 · linear_trans_color · principal_comp · rgb1_to_gray · rgb3_to_gray · access_channel

Same category (color)

trans_from_rgb · trans_to_rgb · linear_trans_color · 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.