riesz op• データ種: qimage → image2d
• 呼び出し: import quatimage; quatimage.monogenic_phase(qimage, display: 'bool' = False) -> 'np.ndarray' (または opsquat.get("monogenic_phase"))
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.
• quaternion_monogenic ファミリ ガイド
• 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。
• quaternion_monogenic — py -3.11 examples/quaternion_monogenic.py
image2d を入力に取れる)riesz_transform · monogenic_signal
riesz)riesz_transform · monogenic_signal · monogenic_amplitude · monogenic_orientation
*Provenance: quatimage.py — QUAT 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.