polarization op• 데이터 종류: polsweep → image2d
• 호출: import specularity; specularity.polarization_separate(images, angles_deg=(0.0, 45.0, 90.0, 135.0), max_violation_frac=0.0)(또는 opsspecular.get("polarization_separate"))
편광판 회전 시퀀스를 무편광 성분과 직선 편광 성분의 복사휘도로 나눕니다. → (diffuse, specular), 둘 다 (H, W).
> 아래 상세 설명은 원문입니다 —— 요약과 제목은 번역되어 있습니다.
Fitting `I(t) = 0.5 (S0 + S1 cos 2t + S2 sin 2t)` per pixel gives
`I_min and I_max` in closed form, and the classical separation
(Wolff & Boult 1991; Nayar, Fang & Boult 1997) reads
`diffuse = 2 * I_min` (the unpolarised radiance)
`specular = I_max - I_min` (the linearly polarised radiance)
with `diffuse + specular = I_min + I_max` = the total scene radiance, so
nothing is lost or invented. Round-tripping
:func:polarization_render through this operator returns the inputs with a
maximum absolute error of 3.9e-16 for the four angles of a
division-of-focal-plane sensor and 4.4e-16 for a bare three-angle sweep
(measured in `tests/test_specularity.py`).
Read the names as shorthand. What is recovered exactly is the
unpolarised and polarised parts. Calling them diffuse and specular assumes
diffuse reflection is unpolarised and specular reflection is fully linearly
polarised — true near Brewster's angle for a dielectric, **false at normal
incidence**, where the specular reflection is unpolarised and this operator
returns all of it as "diffuse", and unreliable for metals. The polarisation
route is complementary to the colour route
(:func:specular_diffuse_split), not a replacement: it needs no illuminant
colour and works on textured, multi-material surfaces, but it needs a
favourable geometry.
*max_violation_frac* is the fraction of pixels allowed to fit a negative
minimum radiance before the call fails. The default 0 is fail-closed: a
negative fitted minimum means the modulation exceeded the mean, which no
analyser can produce, and it usually means the frames and *angles_deg* are
out of order. Raise it to clamp sensor-noise-level violations to zero as a
deliberate, recorded choice.
Raises `ValueError: *images* is not an (N, H, W)` stack of at
least 3 frames, or exceeds :data:MAX_LIGHTS / :data:MAX_STACK_ELEMENTS;
*angles_deg* does not match the frame count or leaves the fit
rank-deficient (two angles equal modulo 180); more than
*max_violation_frac* of the pixels fit a negative minimum.
• specular_photometric 패밀리 가이드
• 샘플 데이터 카탈로그(DL URL / 라이선스) —— 2-D 는 skimage.data(BSD/public)+ 합성, 3-D 는 실데이터 소스(Stanford/PDS 등)의 DL URL.
• 연산자의 내력·참고문헌 —— 이 연산자 족의 바탕이 된 연구/기법의 출처.
• 알고리즘의 정전(저자·연도)과 용도는 위의 패밀리 사용 가이드에 적혀 있습니다.
• poc_polarization_specular — py -3.11 examples/poc_polarization_specular.py
• specular_photometric — py -3.11 examples/specular_photometric.py
image2d 를 입력으로 받는 것)polarization)polarization_render · polarization_dolp_map · polarization_stokes
*Provenance: specularity.py — SPECULAR 연산자 레지스트리. 이 op 노트는 tools/opdocs.py md 가 자동 생성합니다(직접 편집하지 마세요).*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.