rgb_to_xyz — IMGMETRICS `colorspace` op

• Data kinds: rgbimage → rgb

• Call: import fullseye as fs; fs.ledger.rgb_to_xyz(rgb) (to call the implementation directly, import imgmetrics; imgmetrics.rgb_to_xyz(rgb); from the registry, opsimgmetrics.get("rgb_to_xyz"))

Usage

sRGB (`(..., 3)`) → CIE XYZ. The transfer function is removed first, then the matrix is applied.

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

手順: `srgb_to_linear で整数 dtype を [0, 1]` に正規化しつつ伝達関数を

外し(IEC 61966-2-1)、線形 RGB に sRGB(D65)→XYZ の 3x3 行列を掛ける。

白 `(1, 1, 1) は (0.9505, 1.0, 1.0890)` に写る(Y を 1 に正規化した尺度)。

• 入力: 最後の軸が 3 なら形は任意(`(3,) の 1 色、(N, 3)` の色表、

`(H, W, 3)` の画像)。整数 dtype(uint8/uint16 など)は dtype の最大値で割る。

float は `[0, 1] に収まっていなければ MetricContractError(ValueError`

の部分型)。ガンマを外した線形値を渡すと二重にガンマを外すので注意。

• 返り値: 入力と同じ形の float64。

• 失敗: 最後の軸が 3 でない / float が `[0, 1]` の外 / 非有限。

次に `xyz_to_lab を繋ぐのが常道(まとめて rgb_to_lab`)。

Detailed usage guide

• image_difference_metrics 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)

• image_quality_metrics — py -3.11 examples/image_quality_metrics.py

Ops the type connects to (they accept `rgb` as input)

xyz_to_lab

Same category (`colorspace`)

rgb_to_lab · lab_to_rgb · xyz_to_lab

*Provenance: imgmetrics.py — IMGMETRICS operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

rgb_to_xyz — IMGMETRICS colorspace op