tb_spad_deadtime_apply — 2D typed op

• 資料種類:counts → counts

• 呼叫:fullseye.apply(img, "tb_spad_deadtime_apply", 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])

tb_spad_deadtime_apply: input → output

*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。點雲以俯視散點顯示(亮度 = z),一維序列為折線,體資料為沿 z 的最大值投影,影片為中間影格,複數影像為振幅;無法成像的回傳值直接顯示數值。*

掃描旋鈕 a(0.1 / 0.5 / 0.9,另一旋鈕取預設):

▸ tb_spad_deadtime_apply: 旋鈕 a 掃描 (文件網站)

*旋鈕 b 不改變輸出(實測: 0.1 / 0.5 / 0.9 相同)。*

階段(前置運算子 → 本運算子,由左至右):

▸ tb_spad_deadtime_apply: 處理階段 (文件網站)

換別的影像(合成場景 / 照片 / 硬幣。上排為輸入,下排為對應輸出。旋鈕取預設):

▸ tb_spad_deadtime_apply: 其他輸入影像 (文件網站)

用法

用偵測器的死時間使真實光子速率產生失真(計數遺失)。

> 以下的詳細說明為原文 —— 摘要與標題已翻譯。

After every detection a SPAD is blind for a recharge (dead) time tau, so the *measured* rate m is always below the *true* incident rate n. Two classical laws, and this op implements both:

• non-paralysable (default) — an arriving photon during the dead time is simply lost: m = n / (1 + n*tau). Monotonic, saturating at 1/tau.

• paralysable (paralyzable=True) — an arriving photon *restarts* the dead time: m = n * exp(-n*tau). This law peaks at n = 1/tau (where m = 1/(e*tau)) and then falls, so a bright scene can read *darker* than a dim one. That is why no inverse op exists for it (see spad_deadtime_correct).

*rate_hz* is a 1-D array of true rates in counts per second; *dead_time_ns* is the dead time in nanoseconds, defaulting to 50 — the middle of the 10-100 ns range a passively quenched SPAD occupies, and a placeholder to be replaced by the datasheet value, never a measurement of your detector. Returns the measured rates as a float64 1-D array of the same length.

Ground truth (pinned in the tests): at n = 1/tau the non-paralysable law gives exactly n/2; the paralysable law's maximum is exactly 1/(e*tau) at n = 1/tau; both reduce to m = n as n*tau -> 0.

Raises ValueError: negative, non-finite or non-1-D *rate_hz*, a non-positive *dead_time_ns*, and a non-bool *paralyzable*.

Typed bridge of the photon op spad_deadtime_apply into the 2-D evolution registry: the same implementation, called under the op(v, a, b) convention. a drives dead_time_ns (default 50); b is unused.

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。

在 Studio 中試試

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。

img_to_counts 0.50 0.50
tb_spad_deadtime_apply 0.50 0.50

▸ 載入此管線  ·  載入並執行

可執行的範例(實際呼叫該運算子並已驗證的樣例)

下面的範例呼叫的是底層帳本運算子 spad_deadtime_apply。此橋接運算子只是把同一實作適配為 fn(v, a, b) 慣例,行為完全相同(只是呼叫形式不同)。

• photon_timeresolved — py -3.11 examples/photon_timeresolved.py

型別可銜接的下一個運算子(可接受 counts 作為輸入)

identity · tb_spad_deadtime_correct · tb_tcspc_coates_correct · tb_tcspc_irf_convolve · tb_tcspc_background_subtract · tb_dtof_depth · tb_countrate_to_counts · tb_counts_to_countrate

同類別(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 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.