signal op• 数据种类:signal → signal
• 调用: import fullseye as fs; fs.ledger.local_std(x, window=9)(要直接调用实现,import dsp; dsp.local_std(x, window=9);从台账取用则 ops1d.get("local_std"))
带误差界的滑动标准差。
> 以下的详细说明为原文 —— 摘要与标题已翻译。
The 1-D counterpart of the image operator local_std (HALCON's deviation_image): the variance is taken after subtracting the mean (E[x^2] - E[x]^2 loses its significant digits on a signal that sits far from zero), unbiased by n/(n-1), and the residual bias of the square root removed by c4(n), so the estimate of sigma itself is unbiased.
*window* is the number of samples in the sliding window, rounded up to the next odd number so the window can be centred (10 becomes 11). The error bound below is computed from the window actually used, so the number quoted stays true. The 2-D side does the same thing — _k(a) snaps the knob to 3/5/7/9 — and the typed bridge that exposes this op as tb_local_std scales the knob continuously, so an even value arrives whenever the knob lands between two odd ones. The relative standard error of each estimate is 1/sqrt(2(n-1)) — 35 % for a 5-sample window, 11 % for 41. Quote it next to any noise figure:
a rolling sigma over 9 samples is +- 25 %, which is wider than most of the changes people try to read off it.
Returns an array the same length as *x* (the ends are reflected).
• 示例数据目录(下载 URL / 许可证) —— 2-D 用 skimage.data(BSD/公有领域)加合成图,3-D 给出真实数据源(Stanford/PDS 等)的下载 URL。
• 算子来历与参考文献 —— 该算子族所依据的研究/方法出处。
• 算法的正典(作者、年份)与用途见上面的族使用指南。
• gallery2d_texture_freq — py -3.11 examples/gallery2d_texture_freq.py
signal 作为输入)create_funct_1d_array · create_funct_1d_pairs · smooth_funct_1d_gauss · smooth_funct_1d_mean · derivate_funct_1d · integrate_funct_1d · zero_crossings_funct_1d · local_min_max_funct_1d
signal)lowpass · highpass · bandpass · envelope · rms · quantize · companding_mu_law · resample
*Provenance: dsp.py — ONED 算子登记表。本条目由 tools/opdocs.py md 自动生成(请勿手工编辑)。*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.