xldgeom op• 資料種類:contour → feature
• 呼叫:fullseye.apply(img, "xg_orientation", a=0.5, b=0.5)(2-D 的模型是一張圖 + 兩個純量旋鈕 a,b∈[0,1])
• HALCON 對應:orientation_points_xld(其含義與參數可參考 HALCON 手冊)
主軸方向 [度],摺疊到 [0,180) 並除以 180。
> 以下的詳細說明為原文 —— 摘要與標題已翻譯。
Angle is measured from the +x (column) axis; multiply the result by 180 to
recover degrees. Line orientation is defined mod 180, so a line at theta and
theta+180 map to the same value.
Discontinuity (inherent, documented): a line orientation lives on a circle of
180 degrees, and this op unrolls it to [0, 1), so the wrap sits at HORIZONTAL —
a line tilted +0.001 deg returns ~0.0 while -0.001 deg returns ~0.9999. Any
single-scalar unrolling has a seam somewhere; callers that need continuity
across horizontal should compare orientations on the doubled angle
(cos 2*theta, sin 2*theta) or take the difference mod 1. The closing point of a
closed contour is not double-counted in the PCA.
• 範例資料目錄(下載 URL / 授權) —— 2-D 用 skimage.data(BSD/公有領域)加合成圖,3-D 給出真實資料源(Stanford/PDS 等)的下載 URL。
• 運算子來歷與參考文獻 —— 該運算子族所依據的研究/方法出處。
• 演算法的正典(作者・年份)與用途見上面的族使用指南。
• gallery2d_geometry — py -3.11 examples/gallery2d_geometry.py
feature 作為輸入)xldgeom)xg_moments · xg_area_center · xg_eccentricity · xg_elliptic_axis · xg_height_width_ratio · xg_regress_contours · xg_clip_contours · xg_gen_polygons
*Provenance: ops.py — 2D 運算子登記表。本條目由 tools/opdocs.py md 自動產生(請勿手動編輯)。*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.