tb_jitter — 2D `typed` op

• Data kinds: points → points

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

tb_jitter: input → output

*The figure is the actual output on a synthetic 128×128 input. Left: input, right: output. Point clouds are drawn as a top-down scatter (brightness = z), 1-D series as a line plot, volumes as the maximum-intensity projection along z, videos as the middle frame, complex images as magnitude; return values that are not pictures are shown as the values themselves.*

*Knob a does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*

*Knob b does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*

Stages (the ops that come before → this op, left to right):

▸ tb_jitter: stages (docs site)

On other images (synthetic scene / photo / coins. Top row: inputs, bottom row: their outputs. Knobs at default):

▸ tb_jitter: other inputs (docs site)

Usage

Adds isotropic Gaussian noise `N(0, sigma)` to each point (mimicking sensor position noise).

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

`sigma はワールド単位の標準偏差(ユーザ指定パラメータ)。clip` を与えると

各成分の変位を `[-clip, clip]` に切り詰める(外れ変位の抑制)。大 N ではノイズの

平均≈0・標準偏差≈sigma となる。返り値は入力と同形状 `(N,3)`。

• `sigma < 0 は ValueError。sigma == 0` または空入力は入力のコピーを返す。

• `clip は与えるなら > 0(それ以外は ValueError`)。切り詰めは成分ごとなので

変位ベクトルの長さは最大 `√3·clip`。

• `seed で決定論的(np.random.default_rng(seed)`)。同 seed・同形状なら同じノイズ。

• 入力は `(N,3)` の有限値のみ(長さ 3 の 1-D は 1 点に昇格、それ以外や NaN は

`ValueError`)。返り値は float64。

• 位置合わせ(`register_fpfh 等)のノイズ耐性を測るとき、sigma` を点間隔

(`voxel_grid_downsample` の格子幅など)に対する比で決めると条件を比較しやすい。

2-D 進化レジストリへ橋渡しした 3d の op `jitter。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、a も b` 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.

Try it in Studio

The program below has been verified to run (same input as the figure). In Studio's help this block becomes buttons that load and run it on the spot.

img_to_points 0.50 0.50
tb_jitter 0.50 0.50

▸ Load this pipeline · Load & run

Runnable examples (verified samples that actually call this op)

The examples below call the underlying ledger op jitter. This bridge op is the same implementation adapted to the fn(v, a, b) convention, so the behaviour carries over unchanged (only the call form differs).

• augment_pointcloud — py -3.11 examples_3d/augment_pointcloud.py

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

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

Same category (`typed`)

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

*Provenance: ops.py — 2D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

tb_jitter — 2D typed op