typed op• Data kinds: signal → signal
• Call: fullseye.apply(img, "tb_zero_crossings_funct_1d", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
*No figure: this op takes signal as input. A Studio program starting from an image cannot reach that type — see the runnable examples below for how it is used.*
Indices where the function changes sign (HALCON `zero_crossings_funct_1d`).
Returns the integer indices `i with sign(y[i]) * sign(y[i+1]) < 0` —
the sample *before* each crossing. An empty input returns an empty index
array (degenerate case, not an error).
Honest limitation: the test is a strict sign product, so a crossing that
lands exactly on a zero sample (`[-1, 0, 1]`) is *not* reported, nor is a
touch of zero without a sign change (`[1, 0, 1]`).
:param y: 1-D function (may be empty).
:returns: int index array (possibly empty).
:raises ValueError: non-1-D / NaN / Inf input.
Typed bridge of the 1d op `zero_crossings_funct_1d 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.
• 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.
• (none yet)
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_abs_funct_1d · tb_negate_funct_1d
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.