rounded_rect — ANNOTATE shape op

• Data kinds: image2d → image2d

• Call: import fullseye as fs; fs.ledger.rounded_rect(img, rect, radius=8, color='neutral', width=2, fill=False, alpha=1.0, scheme='okabe_ito') (to call the implementation directly, import annotate; annotate.rounded_rect(img, rect, radius=8, color='neutral', width=2, fill=False, alpha=1.0, scheme='okabe_ito'); from the registry, opsannotate.get("rounded_rect"))

Usage

A rounded rectangle (filled with fill=True). For backing plates and enclosing boxes.

Raises

ValueError

rectangle outside the image, radius negative or exceeding half a side, alpha outside [0,1].

Drawing: inside-ness is judged by the distance from the pixel centre to the "rectangle with rounded corners"; with fill=False only a band max(1, width) px wide from the outer border is applied (1 step of distance test, no anti-aliasing). Compositing is out = m*color + (1-m)*img multiplied by alpha.

• img: (H, W) / (H, W, 1|3|4). Returns a copy converted to float64 and clipped to [0, 1] (the input is not changed). NaN/Inf is ValueError.

• rect: (x, y, w, h), x = column, y = row. Rounded to integers; w, h > 0, and it must lie entirely within the image (overhang is not trimmed but ValueError). The pixels covered are x .. x+w-1, y .. y+h-1.

• radius: corner radius [px], 0 <= radius <= min(w, h)/2. 0 gives an ordinary rectangle.

• color: a palette role name ("neutral" etc., resolved via scheme) or RGB in [0, 1]. For grey images the mean of the RGB is used.

• Return value: float64 of the same shape as the input.

For building by hand the same look as the backing of text_box or the frame of annotate_legend.

Detailed usage guide

• figure_annotation family guide

Background guides (the physics and conventions behind this op)

• dataset_conventions — Training-dataset conventions — COCO / YOLO / VOC and pitfalls in visual inspection

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

• poc_machine_condition_fusion — py -3.11 examples/poc_machine_condition_fusion.py

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

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

Same category (shape)

filled_polygon · arc · ellipse

*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.