xsitk_moments_thresh — 2D extra op

Data kinds: imageregion

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

xsitk_moments_thresh: 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.*

Sweeping knob a (0.1 / 0.5 / 0.9, the other knob at its default):

xsitk_moments_thresh: knob a sweep (docs site)

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

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

xsitk_moments_thresh: other inputs (docs site)

*The 4th column is a colour (H,W,3) input. This op handles colour without crossing channels (it does not convolve the colour channel as a third spatial axis).*

Usage

Binarization by the moment-preserving method (SimpleITK `MomentsThreshold`, Tsai's method). Selects the threshold so that the statistical moments (mean, variance, etc.) of the binarized histogram match those of the original histogram.

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

`a はヒストグラムのビン数(64〜256)を振る。b` は未使用。xsitk_maxentropy_thresh・xsitk_huang_thresh とは閾値選択の基準が異なるだけで、同じ入出力形。

Blank frame (measured): feeding an image of uniform brightness makes every pixel foreground (1), regardless of the brightness. A frame that is blown out, occluded, or simply has no subject comes back as “100 % defective”, so test for uniformity upstream and reject such frames.

Detailed usage guide

gallery2d_color_artistic family guide

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.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

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.

xsitk_moments_thresh 0.50 0.50

▸ Load this pipeline  ·  Load & run

Runnable examples (verified samples that actually call this op)

gallery2d_color_artisticpy -3.11 examples/gallery2d_color_artistic.py

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

identity · reg_erode · reg_dilate · reg_open · reg_close · fill_holes · select_largest · remove_small

Same category (extra)

xsitk_curvature_flow · xsitk_minmax_curv_flow · xsitk_curv_aniso_diff · xsitk_laplacian_sharpen · xsitk_grayscale_fillhole · xsitk_grayscale_grindpeak · xsitk_opening_by_recon · xsitk_closing_by_recon


*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.