light_transport op• Data kinds: images → table
• Call: import fullseye as fs; fs.ledger.separate_direct_global(images, fill=0.5, black_level=0.0, scheme='shift') (to call the implementation directly, import lighttransport; lighttransport.separate_direct_global(images, fill=0.5, black_level=0.0, scheme='shift'); from the registry, opsoptics.get("separate_direct_global"))
Separate direct and global (interreflection) components from images under shifted high-frequency patterns, from per-pixel L_max and L_min (Nayar et al. 2006).
With a fraction α of the projector lit in a pattern of high frequency, a pixel whose scene point is lit sees L_d + α L_g (the global part only depends on the average power when it is smooth over the pattern period) and an unlit one sees only the global part.
• scheme="shift" — every image is the same pattern (fill α) shifted: L_max = L_d + (α + b(1−α)) L_g, L_min = b L_d + (α + b(1−α)) L_g, so L_d = (L_max − L_min)/(1 − b).
• scheme="complement" — a pattern and its complement (Nayar et al. eq. 8): L_max = L_d + (α + b(1−α)) L_g, L_min = b L_d + (1 − α + αb) L_g (assumes L_max is the lit image).
Both reduce to L_d = L_max − L_min, L_g = 2 L_min for α = 0.5, b = 0. *black_level* b is the relative brightness of an unlit projector pixel.
Returns a dict (a table) with direct, global, l_max, l_min (each (H, W)).
Raises ValueError: fewer than 2 images, non-2-D or non-finite; *fill* outside (0, 1); *black_level* outside [0, 1); unknown *scheme*.
Every optics op validates its input before computing (nothing slips through silently):
• Units are baked into the argument name — _mm / _um / _deg / _mrad. Confusing mm with µm does not crash; it yields a plausible-looking wrong answer, so the name prevents it. Nothing here guesses the unit from the magnitude.
• Strings raise ValueError — float('50') succeeds, so an unparsed configuration value would slip through as a length (measured: thin_lens('50', '200') returned a plausible 66.667 mm). bool is refused too, as the implicit promotion True == 1.
• complex / masked arrays raise ValueError (real-valued slots only; silently dropping the imaginary part or peeling off the mask is refused). NaN/Inf raises ValueError on every input.
• Division by zero and its relatives are refused by name: focal length 0, radius of curvature 0, refractive index <= 0, a fully opaque aperture (all zeros, so the normalisation is 0/0), a PSF whose sum is <= 0, a Stokes vector with S0 = 0, and an object sitting at the front focal point (the image is at infinity).
• Only two ops return a non-finite value, and both state it as a contract: depth_of_field returns far_mm = inf beyond the hyperfocal distance (that is what the hyperfocal distance means), and gaussian_beam returns wavefront_radius_mm = inf at the waist (the radius of curvature of a plane wavefront). Both also return a finite companion (far_is_infinite / curvature_per_mm). Any other silent NaN/Inf is detected internally and raises ValueError — "float64 overflowed" and "the answer is infinite" are different claims, so the first is never returned wearing the face of the second.
• Size caps: generated grids are capped by optics.MAX_GRID (4096); supplied fields/PSFs/apertures by optics.MAX_FIELD_ELEMENTS (2^24); ABCD element chains by optics.MAX_SYSTEM_ELEMENTS (1024); Zernike by MAX_ZERNIKE_TERMS (512) / MAX_ZERNIKE_ORDER (40) / MAX_ZERNIKE_BASIS (2^25). This closes, fail-closed, the paths where a small argument triggers a huge internal allocation (measured: n_max=40 × 4096² needs 108 GB).
• Physically impossible states are refused too: a Stokes vector with degree of polarisation > 1, negative transmittance, negative intensity, and invalid Zernike indices such as n-|m| odd.
• 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.
• The canonical algorithm (author, year) and its uses are named in the family usage guide above.
• poc_interreflection_fringe_error — py -3.11 examples/poc_interreflection_fringe_error.py
table as input)abcd_matrix · wavefront_stats · sfr_from_edge · paraxial_trace · seidel_coefficients · spot_stats · tolerance_analysis · wavefront_from_opd
light_transport)groove_profile · form_factors_2d · transport_matrix_radiosity · high_frequency_patterns · render_transport · fringe_multipath_phase_error · predict_fringe_phase_error · micro_phase_decode
*Provenance: lighttransport.py — OPTICS 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.