fly_lgmd_eta — FLYVISION looming op

数据种类:signalsignal

调用: import fullseye as fs; fs.ledger.fly_lgmd_eta(theta_signal, dt_s, alpha=4.7, delay_s=0.0)(要直接调用实现,import flyvision; flyvision.fly_lgmd_eta(theta_signal, dt_s, alpha=4.7, delay_s=0.0);从台账取用则 opsflyvision.get("fly_lgmd_eta"))

用法

> 该算子的说明尚无译文,以下照原文给出。

LGMD/eta looming response from an expanding subtended angle.

The multiplicative looming model::

eta(t) = theta'(t - delay) * exp(-alpha * theta(t - delay))

where *theta_signal* is the object's full subtended angle over time, in

radians. The product of the angular expansion rate and an exponentially

decaying gain gives a response that peaks a fixed time before collision.

theta_signal: the full subtended angle per sample, radians.

dt_s: the sample interval, seconds.

alpha: the gain-decay constant.

delay_s: a fixed neural delay, seconds.

Returns a 1-D float64 array `eta(t)` of the same length.

Ground truth: for an object of half-size `l approaching at speed |v|`,

`eta peaks at a time-to-contact of alpha*l/|v| - delay_s` (Gabbiani et

al. Eq. 5), where the subtended angle is exactly `2*atan(1/alpha)` (Eq. 6;

24.0 degrees for `alpha = 4.7`) — both pinned in the tests.

Raises `ValueError`: a non-1-D / empty / too-short (< 3) / non-finite

*theta_signal*, a signal over :data:MAX_SIGNAL_POINTS, a non-positive *dt_s*

/ *alpha*, and a negative *delay_s*.

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。

• 算法的正典(作者・年份)与用途见上面的族使用指南

可运行的示例(实际调用该算子并已验证的样例)

poc_fly_visionpy -3.11 examples/poc_fly_vision.py

类型可衔接的下一个算子(可接受 signal 作为输入)

fly_emd_response · fly_tau_from_expansion · fly_dsi

同类别(looming)

fly_tau_from_expansion


*Provenance: flyvision.py — FLYVISION 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.