typed op• 数据种类:lightfield → image
• 调用:fullseye.apply(img, "tb_lf_depth_from_focus", a=0.5, b=0.5)(2-D 的模型是一张图 + 两个标量旋钮 a,b∈[0,1])
*图为在 128×128 合成输入上实际运行的输出。左为输入，右为输出。点云以俯视散点显示(亮度 = z)，一维序列为折线，体数据为沿 z 的最大值投影，视频为中间帧，复数图像为幅值；无法成像的返回值直接显示数值。*
*输出以类 viridis 伪彩色显示(深紫 = 小，黄 = 大)，便于读取距离、相位、方向、深度这类“量的场”。*
*旋钮 a 不改变输出(实测: 0.1 / 0.5 / 0.9 相同)。*
*旋钮 b 不改变输出(实测: 0.1 / 0.5 / 0.9 相同)。*
阶段(前置算子 → 本算子，从左到右):
▸ tb_lf_depth_from_focus: stages (docs site)
换别的图像(合成场景 / 照片 / 硬币。上排为输入，下排为对应输出。旋钮取默认):
▸ tb_lf_depth_from_focus: other inputs (docs site)
在重聚焦扫描中根据清晰度峰值得到的逐像素斜率。
> 以下的详细说明为原文 —— 摘要与标题已翻译。
Refocus at every slope in *slopes*, measure local sharpness (*measure*:
`laplacian` = summed modified Laplacian, the classical depth-from-focus
operator; `variance = local variance; gradient` = local gradient
energy) in a `window x window` neighbourhood, and take the slope at which
each pixel is sharpest. With `subpixel=True` (default) the peak is refined
by fitting a parabola through the winning sample and its two neighbours on a
uniformly spaced sweep — on a non-uniform sweep the refinement is
skipped rather than applied with the wrong spacing.
Unbiased where :func:lf_epi_slope is not: measured 2026-09-01 on a
5x5x64x64 synthetic field over a 121-point sweep from -3 to +3, the argmax
landed exactly on the true slope in 18 of 18 combinations (true slopes
0.0, +0.5, +1.0, +1.5, +2.0, -1.0 crossed with texture sigma 1.5 / 3.0 /
5.0 px), and the sub-pixel refinement left every one of them unmoved. Its
resolution, though, is whatever you put in *slopes* — it cannot see a plane
you never refocused on.
Returns `(slope_map, sharpness): the (H, W)` map of estimated slopes
(in px per angular step) and the `(H, W)` peak focus-measure value, which
is the honest confidence — a textureless pixel has no sharpness peak, gets
an essentially arbitrary slope, and its `sharpness` is ~0. Threshold on it
rather than trusting the map everywhere.
Raises `ValueError`: *lf* not a valid light field, *slopes* empty /
over :data:MAX_STACK_SLICES / over :data:MAX_STACK_ELEMENTS / containing
a non-finite or over-large value, an even or non-positive *window*, unknown
*measure* / *interp* / *edge*.
Typed bridge of the lightfield op `lf_depth_from_focus into the 2-D evolution registry: the same implementation, called under the op(v, a, b) convention. This op has no tunable parameter; a and b` are unused.
• 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。
下面的程序已确认可以运行(与图相同的输入)。在 Studio 帮助中，此块会变成按钮，可当场加载并运行。
img_to_lightfield 0.50 0.50 tb_lf_depth_from_focus 0.50 0.50
▸ Load this pipeline · Load & run
下面的示例调用的是底层账本算子 lf_depth_from_focus。此桥接算子只是把同一实现适配为 fn(v, a, b) 约定，行为完全相同(只是调用形式不同)。
• lightfield_depth — py -3.11 examples/lightfield_depth.py
• poc_compound_eye — py -3.11 examples/poc_compound_eye.py
• poc_lightfield_depth — py -3.11 examples/poc_lightfield_depth.py
image 作为输入)identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter
typed)tb_points_to_voxel · tb_estimate_point_normals · tb_iss_keypoints · tb_project_points · tb_render_point_depth · tb_statistical_outlier_removal · tb_radius_outlier_removal · tb_voxel_grid_downsample
*Provenance: ops.py — 2D 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.