tb_specular_free_transform — 2D `typed` op

• Data kinds: rgbimage → rgbimage

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

Usage

Project out the illuminant direction: the part of the image a highlight cannot touch. → (H, W, 3).

`I - (I.G) G for the unit illuminant colour G`. Under the dichromatic

model the interface term is `m_s * G`, so it lies entirely in the removed

direction and the result is invariant to any specular term whatsoever —

exactly, for any lobe shape, any strength, any spatial pattern. That is the

specular-invariant subspace of Mallick et al. (2005); this operator is the

projection itself, with no rotation into named channels, so it stays in RGB

and composes with the rest of the family.

Use it when the *shape* of the specular lobe is unknown or the surface is

textured — feature matching, edge detection and correlation all work in this

subspace without any of the assumptions

:func:specular_diffuse_split needs.

This is a projection, not a picture. The result loses one of three

degrees of freedom (its component along `G` is exactly zero everywhere)

and, for an image with negative values after black-level subtraction, keeps

them. It is not a displayable "highlight-removed photo" and does not claim

to be; for that, use :func:specular_diffuse_split.

Raises `ValueError: *image_rgb* is not a valid (H, W, 3)` linear

RGB image (see :func:specular_diffuse_split); *illuminant_rgb* is not a

non-zero 3-vector.

Typed bridge of the specular op `specular_free_transform 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_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_specular_free_transform — 2D typed op