unproject_spherical — 3D `lidar_projection` op

• Data kinds: image2d → points

• Call: import fullseye as fs; fs.ledger.unproject_spherical(range_img, v_fov=(-25.0, 15.0)) -> 'np.ndarray' (to call the implementation directly, import spherical_proj; spherical_proj.unproject_spherical(range_img, v_fov=(-25.0, 15.0)) -> 'np.ndarray'; from the registry, ops3d.get("unproject_spherical"))

Usage

Spherical range image → 3-D points (M, 3). Only the cells with range > 0 are back-projected, at their bin-centre angles.

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

:func:project_spherical の逆。行/列からビン中心の (elevation, azimuth) を復元し、

格納 range を slant distance として球面 → 直交座標へ戻す。空(全 0)なら (0, 3) を返す。

• `range_img: (v_res, h_res) の 2-D 配列(非 2-D・サイズ 0 は ValueError)。range > 0` の

セルだけを点にする(0 = 空セル、負値も無視)。

• `v_fov`: 投影時と同じ (v_min, v_max) [度]。違う値を渡すと仰角がずれた点群になる(整合性は

検査できない)。

列 c → 方位角 `az = (c + 0.5) / h_res · 2π - π、行 r → 仰角 `el = v_min + ((v_res-1-r) + 0.5)

/ v_res · (v_max - v_min)`(度 → rad)とし、x = r cos(el) cos(az)、y = r cos(el) sin(az)`、

`z = r sin(el)。点の並びは np.nonzero` の行優先順(行 0 から)。ビン中心へ戻すので元の点とは

最大でおよそ「半セル角 × range」ずれ、投影で捨てられた(同セルの奥・FOV 外の)点は戻らない。

往復すると点数は一般に減る。

Background guides (the physics and conventions behind this op)

• depth_sensors — 深度センサの知識 — 測距原理・実機の値・欠測の出方

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.

Runnable examples (verified samples that actually call this op)

• lidar_projection — py -3.11 examples_3d/lidar_projection.py

Ops the type connects to (they accept `points` as input)

points_to_voxel · gaussians_to_voxel · estimate_point_normals · to_points · match_points_ncc · match_pca · moment_axes · icp_point2point_3d

Same category (`lidar_projection`)

project_spherical · project_cylindrical

*Provenance: spherical_proj.py — 3D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

unproject_spherical — 3D lidar_projection op