tb_quaternion_to_rgb — 2D `typed` op

• Data kinds: qimage → rgbimage

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

Usage

Vector part of a quaternion image, as linear RGB. → (H, W, 3).

The inverse of :func:rgb_to_quaternion — and, by default, a *checked*

inverse. A quaternion image that picked up a scalar component somewhere (a

Hamilton product with a non-pure quaternion, a monogenic signal handed here

by mistake) is refused rather than silently truncated, because dropping

the `w` component is exactly the kind of loss that produces a plausible

picture from the wrong data. Pass `allow_scalar=True` to opt in to the

truncation when it is what you meant.

The tolerance is relative to the field's own peak modulus

(:data:_MONOGENIC_K_TOL, 1e-9): a quaternion image that really is pure

carries `|w|` at the 1e-17 level after a round trip through two FFTs, and

anything with a meaningful scalar part is many orders above that. Nothing

real lives in between.

Raises `ValueError: *qimage* is not a finite (H, W, 4)` array; or

it has a non-negligible scalar part and `allow_scalar` is False.

Typed bridge of the quat op `quaternion_to_rgb 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.

Runnable examples (verified samples that actually call this op)

• (none yet)

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

identity · tb_wetness · tb_sensor_capture · tb_specular_diffuse_split · tb_specular_coefficient_map · tb_specular_free_transform · tb_rgb_to_quaternion

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).*

tb_quaternion_to_rgb — 2D typed op