fullseye

tb_monogenic_phase — 2D typed op

tb_monogenic_phase: input → output

図は合成の入力 128×128 で実際に走らせた出力。左が入力、右が出力。点群は上から見た散布(明るさ = z)、1-D 列は折れ線、体積は z 方向の最大値投影、動画は中央フレーム、複素画像は振幅、絵にならない返り値は値そのもの。

出力は viridis 風の疑似カラー(暗い紫 = 小、黄 = 大)。距離・位相・向き・深度のような「量の場」を読むため。

つまみ a は出力を変えない(実測: 0.1 / 0.5 / 0.9 で同一)。

つまみ b は出力を変えない(実測: 0.1 / 0.5 / 0.9 で同一)。

段階(前置きの op → この op。左から順):

tb_monogenic_phase: stages

別の画像でも(合成シーン / 写真 / 硬貨。上段が入力、下段がその出力。つまみは既定):

tb_monogenic_phase: other inputs

使い方

Local phase atan2(|R|, f) of a monogenic signal. → (H, W).

In ``[0, pi]`` — the monogenic phase is measured against the *magnitude* of
the Riesz vector, whose sign is carried by the orientation instead, so the
range is a half turn rather than a full one. That is the standard
convention (Felsberg & Sommer) and it is stated here because a caller
arriving from ``complexops.cx_phase`` (whose raw range is ``(-pi, pi]``) will
otherwise assume a full turn and see a "wrapped" map that is not wrapped.

``display=True`` maps ``[0, pi]`` to ``[0, 1]`` for viewing; the default is
``False`` — the **opposite** of ``cx_phase``'s default, deliberately,
because the consumers of this quantity in this module are numerical, and a
display scaling that arrives silently in a measurement is a factor of ``pi``
that nothing announces.

Phase is the quantity a translation shifts linearly, which is why the whole
motion half of this module reads it. For an edge, phase 0 means the peak of
a bright line, ``pi/2`` a step edge and ``pi`` the peak of a dark line — the
local *structure type*, independent of contrast.

**Raises** ``ValueError``: the input is not a valid quaternion field, or its
``k`` component is non-zero; *display* is not a bool.

Typed bridge of the quat op monogenic_phase 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.

参考(サンプルデータ・文献)

Studio で試す

下のプログラムは実際に走ることを確かめてある(図と同じ入力)。Studio のヘルプではこのブロックがボタンになり、その場で読み込んで実行できる。

img_to_monogenic 0.50 0.50
tb_monogenic_phase 0.50 0.50

実行できる例(この op を実際に呼ぶ検証済みサンプル)

次の例は元の台帳 op monogenic_phase を呼ぶもの。この橋渡し op は同じ実装を fn(v, a, b) 規約に合わせただけなので、挙動はそのまま当てはまる(呼び出し形だけ違う)。

型が繋がる次の op(image を入力に取れる)

identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter

同カテゴリ(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 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.