tb_quantize — 2D typed op

数据种类:signalsignal

调用:fullseye.apply(img, "tb_quantize", a=0.5, b=0.5)(2-D 的模型是一张图 + 两个标量旋钮 a,b∈[0,1])

tb_quantize: input → output

*图为在 128×128 合成输入上实际运行的输出。左为输入,右为输出。点云以俯视散点显示(亮度 = z),一维序列为折线,体数据为沿 z 的最大值投影,视频为中间帧,复数图像为幅值;无法成像的返回值直接显示数值。*

扫描旋钮 a(0.1 / 0.5 / 0.9,另一旋钮取默认):

tb_quantize: knob a sweep (docs site)

*旋钮 b 不改变输出(实测: 0.1 / 0.5 / 0.9 相同)。*

阶段(前置算子 → 本算子,从左到右):

tb_quantize: stages (docs site)

换别的图像(合成场景 / 照片 / 硬币。上排为输入,下排为对应输出。旋钮取默认):

tb_quantize: other inputs (docs site)

用法

给出误差模型的标量量化器(可选抖动)。

> 以下的详细说明为原文 —— 摘要与标题已翻译。

*bits* sets the number of levels `L = 2**bits` over the signal's own

min..max range. *mode* is `"round" (mid-tread, unbiased) or "truncate"`

(floor, the convention PIL's posterize and most fixed-point casts use).

The two differ by more than a rounding convention. With step

`Delta = range/(L-1) both have error variance Delta**2/12`, but

truncation also carries a mean of `-Delta/2`, so its mean square error is

truncate: Delta2/12 + (Delta/2)2 = Delta**2/3

round: Delta**2/12

— a factor of 4. Anything that measures a level (not just displays it)

must round.

*dither* adds noise before quantising so the error stops being a function

of the signal: `"tpdf"` (triangular, the audio standard — two uniform draws

summed, so the error's variance no longer depends on the sample value) or

`"rpdf"` (one uniform draw). Dither raises the total error power but removes

the correlation that makes quantisation audible as distortion rather than as

hiss. `seed` fixes the draw so the op stays deterministic.

Applicability. (1) The range is taken from *this* signal, so two signals

quantised separately do not share a scale. (2) `bits=1` with no dither is a

comparator, not a quantiser — the error model does not apply. (3) The error

model assumes the signal moves by more than a step between samples; on a flat

stretch the error is a constant offset, not noise.

Typed bridge of the 1d op `quantize into the 2-D evolution registry: the same implementation, called under the op(v, a, b) convention. a drives bits (default 8); b` is unused.

参考(示例数据・文献)

• 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。

在 Studio 中试试

下面的程序已确认可以运行(与图相同的输入)。在 Studio 帮助中,此块会变成按钮,可当场加载并运行。

img_to_signal 0.50 0.50
tb_quantize 0.50 0.50

▸ Load this pipeline  ·  Load & run

可运行的示例(实际调用该算子并已验证的样例)

下面的示例调用的是底层账本算子 quantize。此桥接算子只是把同一实现适配为 fn(v, a, b) 约定,行为完全相同(只是调用形式不同)。

poc_cold_chain_excursionpy -3.11 examples/poc_cold_chain_excursion.py

类型可衔接的下一个算子(可接受 signal 作为输入)

identity · tb_create_funct_1d_array · tb_smooth_funct_1d_gauss · tb_smooth_funct_1d_mean · tb_derivate_funct_1d · tb_integrate_funct_1d · tb_zero_crossings_funct_1d · tb_abs_funct_1d

同类别(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 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.