trans_to_rgb — 2D color op

Data kinds: colorcolor

Call: fullseye.apply(img, "trans_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: trans_to_rgb (the HALCON reference is a useful guide to its meaning and parameters)

Usage

The inverse transform from a color space back to RGB. Claimed to correspond to HALCON's `trans_to_rgb` (conversion from an arbitrary color space to RGB color space), but the implementation only supports the single direction HSV to RGB.

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

`trans_from_rgb` は a で 4 色空間(HSV/Lab/YUV/XYZ)を選べるのに対し、

この逆変換は常に入力を HSV とみなして `cv2.COLOR_HSV2RGB` を掛ける。

Lab/YUV/XYZ から呼んだ場合は色空間の解釈を誤ったまま変換するため、

出力は破綻した色になる。a, 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 · linear_trans_color · principal_comp · rgb1_to_gray · rgb3_to_gray · access_channel · edges_color

Same category (color)

cfa_to_rgb · trans_from_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.