depth op• 데이터 종류: lightfield → image2d
• 호출: import fullseye as fs; fs.ledger.lf_epi_slope(lf, *, window=9, min_energy=1e-10)(구현을 직접 호출하려면 import lightfield; lightfield.lf_epi_slope(lf, *, window=9, min_energy=1e-10), 원장에서 가져오려면 opslightfield.get("lf_epi_slope"))
• 원장 경유의 반환값: fullseye.ledger.lf_epi_slope(...) 는 선언된 out 형 image2d 의 값만 반환합니다(실제 함수는 보조 정보도 반환). 버려진 쪽이 필요하면 fullseye.ledger.lf_epi_slope.raw(...) 를 쓰거나 lightfield.lf_epi_slope 를 직접 호출하세요.
EPI 선의 방향으로부터 화소별 기울기를 냅니다(구조 텐서, 1 패스).
> 아래 상세 설명은 원문입니다 —— 요약과 제목은 번역되어 있습니다.
A scene point traces a straight line in the epipolar-plane image (lf_epi), so along that line the intensity is constant:
E_u + s * E_x = 0. Accumulating that constraint over the whole angular grid and a window x window spatial neighbourhood gives the closed-form least-squares slope s = -(J_ux + J_vy) / (J_xx + J_yy) with J_ab = sum(E_a * E_b) — one pass over the light field, no sweep, both the horizontal and vertical EPI directions pooled.
This estimator is biased, and the bias is the reason to also run lf_depth_from_focus. It is ordinary (not total) least squares on finite differences, so it needs the EPI line to advance less than roughly one texture correlation length per view. Measured 2026-09-01 on 5x5x64x64 synthetic fields, median over the interior: with texture sigma = 1.5 px, true +1.00 -> +1.0004, +0.50 -> +0.5285, +1.50 -> +1.3018, +2.00 -> +1.4614; with sigma = 5.0 px the same slopes give +1.0003, +0.5029, +1.4827, +1.9482. Integer slopes on a wrapped field come back within 4e-4 and s = 0 is exact; |s| > 1 is under-estimated, by 27% at s = 2 on the roughest texture. Use it as a fast dense initialiser, not as the final word.
Returns (slope_map, energy): the (H, W) slope map and the (H, W) gradient energy J_xx + J_yy that was the denominator. Pixels whose energy is below *min_energy* have no measurable parallax (a flat patch of sky); their slope is set to 0 and their energy reported as-is, so you threshold on energy instead of being handed a plausible-looking number divided by ~0.
Raises ValueError: *lf* not a valid light field, an angular/spatial shape where *neither* EPI direction carries information (the horizontal EPI needs U >= 2 and W >= 2, the vertical needs V >= 2 and H >= 2), an even or non-positive *window*, a non-positive *min_energy*.
• 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.
• lightfield_depth — py -3.11 examples/lightfield_depth.py
• poc_lightfield_depth — py -3.11 examples/poc_lightfield_depth.py
image2d 를 입력으로 받는 것)lf_from_mla · lf_disparity_to_depth · lf_all_in_focus
depth)lf_depth_from_focus · lf_disparity_to_depth · lf_all_in_focus · lf_plenoptic_design
*Provenance: lightfield.py — LIGHTFIELD 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.