tb_temporal_bandpass — 2D typed op

• 資料種類:video → video

• 呼叫:fullseye.apply(img, "tb_temporal_bandpass", 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_temporal_bandpass: 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_temporal_bandpass: 旋鈕 a 掃描 (文件網站)

掃描旋鈕 b(0.1 / 0.5 / 0.9,另一旋鈕取預設):

▸ tb_temporal_bandpass: 旋鈕 b 掃描 (文件網站)

階段(前置運算子 → 本運算子,由左至右):

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

動態(GIF: 依序顯示影格 / 視點 / 切片。靜態圖是完整版,GIF 為輔助):

tb_temporal_bandpass: animation

用法

對每個像素的時間序列進行理想時域帶通濾波 -> (T, H, W)。

> 以下的詳細說明為原文 —— 摘要與標題已翻譯。

Each pixel is transformed along time, every DFT bin whose frequency lies outside [f_lo, f_hi] (in Hz, magnitude, DC always excluded) is zeroed, and the result is transformed back. Frequency-selective where videops.moving_average and videops.spatiotemporal_gaussian are low-pass; this is the filter isolating "what is happening at 4 Hz".

Exact for a component sitting on a bin: with T frames at fps, a sinusoid at k*fps/T Hz passes with gain 1 and everything else in the band passes untouched. Measured on a bin-centred 4 Hz unit sinusoid in a 64-frame 32 fps clip that also carries a DC offset of 0.5 and a 12 Hz component of amplitude 0.3, the recovered waveform matches the 4 Hz term alone to max|err| = 4.36e-15.

A brick-wall filter rings in time; that is the price of an exact pass-band and it is the same choice the 2012 Eulerian magnification paper makes. The output is zero-mean along time by construction.

Typed bridge of the motionmag op temporal_bandpass into the 2-D evolution registry: the same implementation, called under the op(v, a, b) convention. a picks the centre of the pass-band among the clip's own non-DC DFT bins (0 = the lowest bin, 1 = the Nyquist bin) and b its half-width (0 = one bin, 1 = half the bins on each side). The band edges sit half a bin outside the chosen bins (frame rate fixed at 32 fps), so the band holds at least one bin for any clip of two or more frames. (Until 2026-10-07 the band was a fixed 3-5 Hz, which holds no bin for a 12-frame clip, so every call was refused.)

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_video 0.50 0.50
tb_temporal_bandpass 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 temporal_bandpass。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)。

• motion_magnification — py -3.11 examples/motion_magnification.py

• poc_beam_modal_video — py -3.11 examples/poc_beam_modal_video.py

• poc_motion_magnification — py -3.11 examples/poc_motion_magnification.py

型別可銜接的下一個運算子(可接受 video 作為輸入)

identity · tb_temporal_band_power · tb_temporal_median_window · tb_moving_average_window · tb_background_subtraction_window · tb_frame_difference_causal · tb_exponential_background · tb_exponential_foreground

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.