lf_synthetic_aperture — LIGHTFIELD refocus op

• データ種: lightfield → image2d

• 呼び出し: import fullseye as fs; fs.ledger.lf_synthetic_aperture(lf, slope=0.0, mask=None, *, reduce='mean', interp='linear', edge='nearest') (実装を直接呼ぶなら import lightfield; lightfield.lf_synthetic_aperture(lf, slope=0.0, mask=None, *, reduce='mean', interp='linear', edge='nearest')、台帳から引くなら opslightfield.get("lf_synthetic_aperture"))

使い方

形を変えた開口で再合焦する —— reduce="median" なら遮蔽物越しにも。

> 以下の詳細説明は原文のままです —— 要約と見出しは訳出済み。

Same shift-and-add geometry as lf_refocus, with two additions:

• *mask* — a (V, U) weight array from lf_aperture_mask (or your own). A small mask is a stopped-down aperture: less defocus blur, less light. None weights every view equally.

• *reduce* — how the aligned views are combined. mean is the classical (and linear) synthetic aperture. median is the interesting one: when a foreground occluder covers a *minority* of the views at a pixel, the median rejects it and the background behind it is reconstructed — looking through a fence, or through a rack of parts. max / min are the order-statistic extremes, useful for specular / shadow work. median, max and min use the mask only to *select* views (weight > 0), because an order statistic has no meaningful weighting; that is stated here rather than silently ignoring the weights.

The see-through result is not a metaphor. When fewer than half the views are blocked at a hidden pixel, more than half of them carry the identical background sample and the median is that sample exactly. Measured 2026-09-01 on a 9x9x64x64 field with an occluder covering 25% of the centre view at slope 3.0 (blocking at most 46% of the views at any hidden pixel):

RMS against the true, hidden background was 0.0 for median and 0.159 for mean, with the centre view itself at 0.280. Push the coverage to 35% (up to 60% of views blocked) and the guarantee is gone — the median lands at 0.133, worse than nothing.

Returns a (H, W) 2-D image.

Raises ValueError: *lf* not a valid light field, a *mask* whose shape is not (V, U) or which is non-finite / negative / selects no view, a non-finite or over-large *slope*, unknown *reduce* / *interp* / *edge*.

詳しい使い方ガイド

• lightfield_depth ファミリ ガイド

参考(サンプルデータ・文献)

• サンプルデータ カタログ(DL URL / ライセンス) — 2-D は skimage.data(BSD/public)+ 合成、3-D は実データ源(Stanford/PDS 等)の DL URL。

• 演算子の来歴・参考文献 — この op 族の元になった研究/手法の出典。

• アルゴリズムの正典(著者・年)と用途は上記ファミリ使い方ガイドに記載。

実行できる例(この op を実際に呼ぶ検証済みサンプル)

• lightfield_depth — py -3.11 examples/lightfield_depth.py

• poc_compound_eye — py -3.11 examples/poc_compound_eye.py

型が繋がる次の op(image2d を入力に取れる)

lf_from_mla · lf_disparity_to_depth · lf_all_in_focus

同カテゴリ(refocus)

lf_refocus · lf_focal_stack · lf_aperture_mask


*Provenance: lightfield.py — LIGHTFIELD operator registry. この per-op ノートは tools/opdocs.py md が自動生成(手編集しない)。*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.