shape_from_polarization op• 数据种类:polsweep → table
• 调用: import fullseye as fs; fs.ledger.sfp_normals(sweep, refractive_index=1.5, model='specular', angles_deg=(0.0, 45.0, 90.0, 135.0), violation_tol=0.05, out_of_range='invalid')(要直接调用实现,import sfpolar; sfpolar.sfp_normals(sweep, refractive_index=1.5, model='specular', angles_deg=(0.0, 45.0, 90.0, 135.0), violation_tol=0.05, out_of_range='invalid');从台账取用则 opsoptics.get("sfp_normals"))
• GPU:无(仅 CPU 参考实现)
由偏振扫描得到每个像素表面法线的显式候选集 —— 漫射 2 个,镜面 4 个(天顶 2 × 方位 2)(table)。
> 以下的详细说明为原文 —— 摘要与标题已翻译。
*sweep* is an (N, H, W) stack through linear analysers at *angles_deg* (the polsweep sort; optics.polarization_demosaic gives it from a raw mosaic). Per pixel the sinusoid I(t) = a0 + a1 cos 2t + a2 sin 2t is fitted (the same least-squares fit as specularity.polarization_dolp_map), giving DoLP = hypot(a1, a2)/a0 and AoLP = 0.5 atan2(a2, a1); then dolp_to_zenith and aolp_to_azimuth give the zenith and azimuth candidates.
A fitted minimum below zero (modulation above the mean, DoLP > 1) is impossible for light. Near Brewster's angle the true minimum is ~0, so sensor noise pushes it slightly negative; *violation_tol* is the largest excess DoLP - 1 that is read as noise (DoLP clipped to 1). A larger excess marks the pixel invalid — the frames do not match *angles_deg*, or the pixel saw something other than a polariser sweep. Such a pixel is reported in violation, never silently clipped. (specularity.polarization_dolp_map refuses the whole image instead; a shape map with one hot pixel is still a shape map, so here the decision is per pixel and sfp_disambiguate refuses invalid pixels inside its mask by default.)
*out_of_range*: a DoLP that no zenith produces (diffuse model, above (n^2-1)/(n^2+1)) makes the pixel "invalid" (default) or is "clamp"-ed to the reachable limit and kept, flagged in clamped.
Returns a dict (a table, marked kind == "sfp_candidates"):
• candidates (K, H, W, 3) unit normals; specular order is [low zenith & azimuth 0, low & azimuth 1, high & azimuth 0, high & azimuth 1], diffuse [azimuth 0, azimuth 1]. Zero vectors at invalid pixels (see valid) — never NaN, never a made-up unit normal.
• zenith_deg (1|2, H, W), azimuth_deg (2, H, W), dolp, aolp_deg, intensity (S0) (H, W).
• n_distinct (H, W) — how many genuinely different normals the pixel admits: 4 (specular), 2 at Brewster's angle or for the diffuse model, 0 where nothing fits or the pixel is dark.
• valid (H, W) bool — lit, physically possible and invertible; violation / clamped (H, W) bool — why a pixel is suspect.
• dark (H, W) bool — the fitted mean a0 = S0/2 is at most specularity.POLAR_DARK_K (3) × the noise of the modulation amplitude σ_A = σ̂·√(v₁+v₂) (v = the diagonal of the fit's (MᵀM)⁻¹; σ̂ = one noise level for the image, from the median per-pixel residual of the N > 3 frames, χ²-median corrected), i.e. the DoLP's own noise would be 1/3 or more: no degree of polarisation is defined there, so the pixel is not lit (valid False, n_distinct 0). ★Before 2026-11-09 only a0 > 0 was required, and clipped sensor noise in a dark region (σ 0.001 of a scene peaking at 1) gave DoLP ≈ 1 and Brewster-angle normals on 26–28 % of the dark pixels, all valid. (A first fix used a floor relative to the brightest 1 % of the image, which ignored the noise: it killed a dark diffuse object next to specular highlights and fell into the noise when the bright part was under 1 % of the image.) A frame that does not belong to the sweep raises the residual to the level of the signal, and then every pixel is dark — the sweep defines no DoLP anywhere (fail-closed); the violation flags are still computed independently of dark. With three angles there is no residual and only a0 <= 0 is dark — noise-only dark pixels are not screened.
• dolp_noise (H, W) — the DoLP's noise level σ_A/a0 (0 on unlit pixels — they have no DoLP, see valid / dark), and noisy = lit pixels with dolp_noise > violation_tol — a flag only (valid is not changed by it): their DoLP, hence their zenith, is mostly noise. With three angles dolp_noise is None and noisy all False. ★One σ̂ for the image assumes stationary noise; shot noise grows with the signal, so treat the flag as a screen.
• model, refractive_index, brewster_deg.
Nothing here chooses among the candidates; a single "best" normal map returned at this stage would be a guess dressed as a measurement.
Raises ValueError: not an (N, H, W) stack of >= 3 finite non-negative frames; angles that do not match or do not determine the fit; *violation_tol* outside [0, 1]; index not > 1; unknown *model* / *out_of_range*.
optics 的每个算子都先校验输入再计算(不让任何东西无声通过):
• 单位写进参数名 —— _mm / _um / _deg / _mrad。把 mm 和 µm 弄混不会崩溃,而是给出「看着合理却是错的答案」,所以用命名来防。这里绝不从数值大小去猜单位。
• 字符串一律 ValueError —— float('50') 会成功,于是未解析的配置值会被当成长度混进来(实测:thin_lens('50', '200') 曾返回看着合理的 66.667 mm)。bool 也按 True == 1 的隐式提升拒绝。
• complex / masked array 一律 ValueError(仅接受实数槽位;拒绝无声丢弃虚部或剥掉掩码)。所有输入中的 NaN/Inf 一律 ValueError。但已声明的缺测除外:bottle_fit_from_pattern 的 u_map 以 NaN 接收未能测得的像素(∞ 仍被拒绝)。
• 逐项点名拒绝除零及其近亲:焦距 0、曲率半径 0、折射率 <= 0、全不透明光阑(全为 0,归一化变成 0/0)、总和 <= 0 的 PSF、S0 = 0 的 Stokes 矢量、物体位于前焦点(像在无穷远)。
• 只有两个算子会返回非有限值,而且都写进了契约:depth_of_field 在超焦距以外返回 far_mm = inf(这正是超焦距的定义),gaussian_beam 在束腰处返回 wavefront_radius_mm = inf(平面波前的曲率半径)。两者都同时返回一个有限的搭档(far_is_infinite / curvature_per_mm)。除此之外的无声 NaN/Inf 都在内部检出并 ValueError ——「float64 溢出了」和「答案是无穷大」是两种不同的主张,不能拿后者的脸去交付前者。但已声明的缺测除外:bottle_background_map 对光线不可用的像素(全反射等)在 u_mm 中返回 NaN,并同时返回 valid 掩码和数量。
• 尺寸上限:生成网格受 optics.MAX_GRID(4096)限制,传入的场/PSF/光阑受 optics.MAX_FIELD_ELEMENTS(2^24),ABCD 元件序列受 optics.MAX_SYSTEM_ELEMENTS(1024),Zernike 受 MAX_ZERNIKE_TERMS(512)/ MAX_ZERNIKE_ORDER(40)/ MAX_ZERNIKE_BASIS(2^25)。以 fail-closed 堵住「小参数引发巨大内部分配」的路径(实测:n_max=40 × 4096² 需要 108 GB)。
• 物理上不可能的状态同样拒绝:偏振度 > 1 的 Stokes 矢量、负透过率、负强度、n-|m| 为奇数等非法 Zernike 指标。
• 示例数据目录(下载 URL / 许可证) —— 2-D 用 skimage.data(BSD/公有领域)加合成图,3-D 给出真实数据源(Stanford/PDS 等)的下载 URL。
• 算子来历与参考文献 —— 该算子族所依据的研究/方法出处。
• 算法的正典(作者、年份)与用途见上面的族使用指南。
• poc_shape_from_polarization — py -3.11 examples/poc_shape_from_polarization.py
table 作为输入)abcd_matrix · wavefront_stats · sfr_from_edge · paraxial_trace · seidel_coefficients · spot_stats · tolerance_analysis · wavefront_from_opd
shape_from_polarization)sfp_dolp_model · dolp_to_zenith · aolp_to_azimuth · sfp_render · sfp_disambiguate · sfp_estimate_index · sfp_height
*Provenance: sfpolar.py — OPTICS 算子登记表。本条目由 tools/opdocs.py md 自动生成(请勿手工编辑)。*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.