crosshair — ANNOTATE pointer op

• Data kinds: image2d → image2d

• Call: import annotate; annotate.crosshair(img, xy, color='emphasis', width=1, gap=6, extent=None, scheme='okabe_ito', style=None) (or opsannotate.get("crosshair"))

Usage

The crossing lines of a cut plane (used in MPR). A `gap` keeps the centre clear so it hides nothing.

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

Parameters

----------

xy : (x, y)

交点。

gap : int

中心を空ける半径 [px] (0 で全通し)。

extent : int or None

中心からの腕の長さ[px]。None なら画像の端まで。

Raises

------

ValueError

交点が画像の外、負の gap/extent。

Detailed usage guide

• figure_annotation family guide

Background guides (the physics and conventions behind this op)

• dataset_conventions — 学習データセット規約の知識 — COCO / YOLO / VOC と外観検査での落とし穴

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)

• annotate_gallery — py -3.11 examples/annotate_gallery.py

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

text_box · arrow · leader_line · label_points · legend_box · color_bar · scale_bar · axes_frame

Same category (pointer)

arrow · leader_line · label_points

*Provenance: annotate.py — ANNOTATE 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.