elastic_deform — 3D augment op

Data kinds: pointspoints

Call: import fullseye as fs; fs.ledger.elastic_deform(points, sigma: 'float', alpha: 'float', seed: 'int' = 0) -> 'np.ndarray' (to call the implementation directly, import pcl_augment; pcl_augment.elastic_deform(points, sigma: 'float', alpha: 'float', seed: 'int' = 0) -> 'np.ndarray'; from the registry, ops3d.get("elastic_deform"))

Usage

Elastic deformation by a smooth random displacement field (correlation length `sigma, RMS amplitude alpha`).

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

各点に独立ガウス乱数ベクトルを置き、空間ガウス重み `exp(-d²/2σ²)` で平滑化した

変位場を生成する(近接点は coherent に動く)。場は RMS を 1 に正規化してから

`alpha 倍するので、変位の RMS ノルムはちょうど alpha になる(σ→∞` で場は

定数=剛体並進, `σ→0` で各点独立)。非剛体な物体変形/柔軟物の学習に。

注意(honest): 近傍探索は `cKDTree.query_pairs(r=3σ)σ` が雲の直径に近いほど

ペア数は O(N²) に近づくため、大規模雲では `σ` を局所スケールに保つこと。

`sigma < 0ValueErrorsigma == 0` または 1 点だけの雲では平滑化せず各点

独立の変位になる。`alpha` は検証しない(0 なら無変位、負なら場が反転するだけ)。

`seed で決定論的。返り値は float64 (N,3)` で点数・順序は保たれる(変形前後の

対応が添字で分かるので、非剛体位置合わせの誤差を直接測れる)。空入力は空を返す。

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)

sensor_segpy -3.11 examples_3d/sensor_seg.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 (augment)

jitter · random_rotation · random_scale · random_dropout · cutout


*Provenance: pcl_augment.py — 3D 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.