gmsd — IMGMETRICS perceptual op

• Data kinds: image2d × image2d → scalar

• Call: import fullseye as fs; fs.ledger.gmsd(ref, dist, data_range: 'float' = 255.0, c: 'float' = 170.0) -> 'float' (to call the implementation directly, import iqafsim; iqafsim.gmsd(ref, dist, data_range: 'float' = 255.0, c: 'float' = 170.0) -> 'float'; from the registry, opsimgmetrics.get("gmsd"))

Usage

> This operator's description has not been translated yet. The original text follows as it is.

GMSD = GMS 地図の標準偏差(N−1、原実装の `std2`、論文 式 5)。0 = 同一、大きいほど劣化(lower is better —— MOS との順位相関は負で、

公表表は |ρ| を載せる: TID2013 全体 |SROCC| 0.8038、二次資料 0.8044)。入力 (H, W) か (H, W, 3)(3-ch は Y)。

`iqatid.tid2013_evaluate(root, gmsd, luma="rgb")。**Raises** ValueError: :func:gmsd_map` と同じ、地図が 1 画素(分散が定義されない)。

Detailed usage guide

• image_difference_metrics family guide

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)

• poc_iqa_fsim_gmsd_vif — py -3.11 examples/poc_iqa_fsim_gmsd_vif.py

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

luma_limited_u8 · rank_data · tid2013_index

Same category (perceptual)

fsim · fsimc · fsim_pair · gmsd_map · vifp · phase_congruency_pc

*Provenance: iqafsim.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.