vignette — GFX2D post op

• 資料種類:rgb → rgb

• 呼叫:import gfx2d; gfx2d.vignette(rgb, strength=0.6, radius=1.0, power=2.0)(或 opsgfx2d.get("vignette"))

用法

向四角變暗:`out = rgb * (1 - strength * t**power)`。

> 以下的詳細說明為原文 —— 摘要與標題已翻譯。

`t is the distance from the geometric centre ((h-1)/2, (w-1)/2)`

divided by `radius` times the half-diagonal, clipped at 1. The factor at

`t = 0 is exactly 1, so strength=0` is the exact identity and — for an

odd-sized image, where a pixel actually sits on the centre — that pixel

is returned untouched. An even-sized image has no centre pixel: its four

innermost pixels are 0.707 px out and are already attenuated, which is

geometry rather than a rounding error.

參考(範例資料・文獻)

• 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。

可執行的範例(實際呼叫該運算子並已驗證的樣例)

• gfx2d_scene — py -3.11 examples/gfx2d_scene.py

型別可銜接的下一個運算子(可接受 rgb 作為輸入)

srgb_to_linear · linear_to_srgb · blend_mode · light_mask · normal_map_decode · bloom · chromatic_aberration · film_grain

同類別(post)

bloom · chromatic_aberration · film_grain · color_lut · color_grade · dither · palette_quantize

*Provenance: gfx2d.py — GFX2D 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.