tb_elastic_deform — 2D typed op

Data kinds: pointspoints

Call: fullseye.apply(img, "tb_elastic_deform", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

Usage

Elastic deformation via 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。

2-D 進化レジストリへ橋渡しした 3d の op `elastic_deform。実装は同じで、呼び出し規約だけ op(v, a, b) に合わせてある。この op に調整点は無く、ab` も使われない。

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)

• (none yet)

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

identity · tb_points_to_voxel · tb_estimate_point_normals · tb_iss_keypoints · tb_angle_3points · tb_project_points · tb_render_point_depth · tb_statistical_outlier_removal

Same category (typed)

tb_points_to_voxel · tb_estimate_point_normals · tb_iss_keypoints · tb_angle_3points · tb_project_points · tb_render_point_depth · tb_statistical_outlier_removal · tb_radius_outlier_removal


*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.