delta_e_2000 — IMGMETRICS colordiff op

Data kinds: lab × labimage2d

Call: import imgmetrics; imgmetrics.delta_e_2000(lab1, lab2, kL=1.0, kC=1.0, kH=1.0) (or opsimgmetrics.get("delta_e_2000"))

Usage

CIEDE2000 colour difference (CIE 142-2001).

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

実装が踏み外しやすい 3 か所 ―― 色相角の平均(0/360 をまたぐ扱い)、

275° の回転項彩度ゼロ近傍(`atan2(0, 0)` の扱い)―― は

Sharma, Wu & Dalal (2005) の 34 組の検証対で固定してある

(`CIEDE2000_TEST_PAIRS / tests/test_imgmetrics.py`)。

Parameters

----------

lab1, lab2 : array_like

最後の軸が `(L*, a*, b*)` の配列。ブロードキャストされる。

kL, kC, kH : float

観察条件のパラメトリック係数。既定は基準条件の 1。

Returns

-------

ndarray

ΔE00(最後の軸が落ちた形)。

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_metricspy -3.11 examples/image_quality_metrics.py

Ops the type connects to (they accept image2d as input)

mse · rmse · psnr · ssim · ms_ssim · ssim_map · image_entropy · joint_entropy

Same category (colordiff)

delta_e_76 · delta_e_map


*Provenance: imgmetrics.py — IMGMETRICS 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.