deformation op• 資料種類:image → image
• 呼叫:fullseye.apply(img, "deform_ffd", a=0.5, b=0.5)(2-D 的模型是一張圖 + 兩個純量旋鈕 a,b∈[0,1])

*圖為在 128×128 合成輸入上實際執行的輸出。左為輸入,右為輸出(非影像的回傳值直接顯示其值)。*
三次 B 樣條自由變形(free-form deformation,Rueckert 等,IEEE TMI 1999)。
> 以下的詳細說明為原文 —— 摘要與標題已翻譯。
A coarse control lattice of `n x n spans (n = 2 + int(6b)`, one padding
ring on each side) carries a deterministic smooth displacement pattern
`phi[i,j] = amp * [sin(2 pi j/n), cos(2 pi i/n)]`; the dense displacement
at a pixel is the tensor product of the four uniform cubic B-spline basis
functions of its span coordinate with the surrounding 4x4 control
displacements, so a control point only ever moves the 4 spans it supports.
That field is used as the backward map and the image is bilinearly resampled.
`a sets the amplitude amp = 0.45*a*min(sy,sx)` -- kept under the
`0.48*spacing` injectivity bound of Choi & Lee (2000), so the deformation
stays a fold-free bijection -- and `b the lattice resolution. a = 0`
gives a zero lattice, hence the identity (up to sub-pixel resampling error).
• 範例資料目錄(下載 URL / 授權) —— 2-D 用 skimage.data(BSD/公有領域)加合成圖,3-D 給出真實資料源(Stanford/PDS 等)的下載 URL。
• 運算子來歷與參考文獻 —— 該運算子族所依據的研究/方法出處。
• 演算法的正典(作者・年份)與用途見上面的族使用指南。
下面的程式已確認可以執行(與圖相同的輸入)。在 Studio 說明中,此區塊會變成按鈕,可當場載入並執行。
deform_ffd 0.50 0.50
▸ Load this pipeline · Load & run
• gallery2d_geometry — py -3.11 examples/gallery2d_geometry.py
image 作為輸入)identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter
deformation)*Provenance: ops.py — 2D 運算子登記表。本條目由 tools/opdocs.py md 自動產生(請勿手動編輯)。*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.