contour op• Data kinds: contour → contour
• Call: fullseye.apply(img, "projective_trans_contour_xld", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: projective_trans_contour_xld (the HALCON reference is a useful guide to its meaning and parameters)
Applies a pseudo perspective-shrink depending on column position to each point of the contour (dividing each point's coordinates by `d = 1 + 0.3*a*(col - center)/width). Note that this is an approximation using a simple one-directional scale change rather than a true projective transformation via a 3x3 homography matrix. A stand-in for HALCON's projective_trans_contour_xld` (Apply a projective transformation to an XLD contour.).
> The detailed description below is the original text — the summary and the headings are translated.
`a が収縮の強さを振る。b` は未使用(画像版の
`projective_trans_image とは異なり、この輪郭版は b` を使わない)。
• gallery2d_contour_measure family guide
• 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.
• gallery2d_contour_measure — py -3.11 examples/gallery2d_contour_measure.py
contour as input)identity · select_contours · smooth_contours · fit_line_contours · contours_to_region · count_contours · total_length · select_contours_xld
contour)select_contours · smooth_contours · fit_line_contours · contours_to_region · sk_find_contours · edges_sub_pix · lines_gauss · select_contours_xld
*Provenance: ops.py — 2D 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.