measure_with — IMGMETRICS report op

• Data kinds: metrics × image2d × image2d → metrics

• Call: import fullseye as fs; fs.ledger.measure_with(report, a, b, ms=False) (to call the implementation directly, import imgmetrics; imgmetrics.measure_with(report, a, b, ms=False); from the registry, opsimgmetrics.get("measure_with"))

Usage

Measure another pair under exactly the same conditions as the previous measurement.

Takes the return value of compare_images (including contract) and re-measures using the data_range / bins / ncd_levels recorded there as is.

This is needed because of a type of accident that actually happened in this repo -- only the numbers get copied into figure captions or tables, and the conditions disappear. When 2 separately measured PSNRs are placed side by side, if one used data_range=1.0 and the other 255, a 48.13 dB difference looks like an "improvement". If the conditions are carried along, combinations that cannot be compared are never created in the first place.

At the same time, this is the consumer side of the metrics type. A state where only compare_images produces metrics and nobody consumes it was exactly the "an entry point exists but no consumer op" type this repo has repeatedly stepped into (detected in the 2026-09-02 audit).

Parameters

report : dict

The return value of compare_images, or contract itself.

a, b : array_like

The 2 images to re-measure.

Returns

dict

A report of the same form. contract is identical to the one received.

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)

• image_quality_metrics — py -3.11 examples/image_quality_metrics.py

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

luma_limited_u8 · rank_data · tid2013_index · metrics_table

Same category (report)

compare_images · metrics_table · data_range_of


*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.