tb_stat_zscore — 2D typed op

Data kinds: signalsignal

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

tb_stat_zscore: 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_stat_zscore: stages (docs site)

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

tb_stat_zscore: other inputs (docs site)

Usage

Standardise a 1-D sample: `(x - mean) / std (population ddof=0`).

The result has mean 0 and standard deviation 1 — the common currency for

comparing residuals across scales and flagging outliers (`|z| > 3`).

**A constant input raises `ValueError`** — the decision, stated: with

zero variance the z-score is 0/0. Returning silent zeros would claim "every

point is perfectly average", which is *a* convention but hides upstream

breakage (a sensor stuck at one value would sail through an outlier gate).

Fail-closed instead; a caller who wants the all-zeros convention can catch

this and substitute deliberately.

HALCON: no direct tuple operator (compose `tuple_mean` +

`tuple_deviation` + arithmetic).

Typed bridge of the math op `stat_zscore into the 2-D evolution registry: the same implementation, called under the op(v, a, b) convention. This op has no tunable parameter; a and b` are unused.

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_signal 0.50 0.50
tb_stat_zscore 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 stat_zscore. 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).

math_metrologypy -3.11 examples/math_metrology.py

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

identity · tb_create_funct_1d_array · tb_smooth_funct_1d_gauss · tb_smooth_funct_1d_mean · tb_derivate_funct_1d · tb_integrate_funct_1d · tb_zero_crossings_funct_1d · tb_abs_funct_1d

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).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.