fly_matched_filter — FLYVISION selfmotion op

• Datenarten: table → matrix

• Aufruf: import fullseye as fs; fs.ledger.fly_matched_filter(lattice, axis=(0.0, 0.0, 1.0), motion='rotation', depth_m=1.0) (die Implementierung direkt: import flyvision; flyvision.fly_matched_filter(lattice, axis=(0.0, 0.0, 1.0), motion='rotation', depth_m=1.0); aus dem Register: opsflyvision.get("fly_matched_filter"))

Verwendung

> Für diesen Operator gibt es noch keine Übersetzung. Es folgt der Originaltext unverändert.

The flow field one unit of self-motion writes on the eye — the template a

wide-field neuron is matched to.

Krapp & Hengstenberg measured the local motion sensitivity of single

lobula-plate tangential cells across the whole visual field and found a

structured vector field, one that looks like the optic flow of a particular

rotation of the fly (*Nature* 384:463, 1996). Reading self-motion out of such

a cell is then a matched filter (Franz & Krapp, *Biol. Cybern.* 83:185, 2000):

correlate the measured flow against the template of the motion you are asking

about. This op builds the template, for the isotropic world model — every

point at the same distance — which is the case in which the rotation template

is exactly the geometry and nothing is assumed about the scene:

• `motion="rotation"`: one radian per second about the unit vector *axis*

moves the viewing direction `d at -axis x d`, which is already

tangent to the sphere. Its length is `sin` of the angle between the axis

and the line of sight, so the template is zero on the axis itself.

• `motion="translation"`: one metre per second along *axis*, with every

point at *depth_m* metres, moves it at `-(v - (v.d) d)/Z`. The depth is

an input, not a measurement — translation flow and distance are the same

unknown and no eye can separate them from one frame pair.

lattice: a :func:fly_hex_lattice result. axis: the rotation axis or

translation direction in body coordinates (x forward, y left, z up); it is

normalised, and a zero vector is refused. depth_m: the uniform distance,

`motion="translation"` only.

Returns `(n, 2)` float64 — the azimuth and elevation components of the flow

at each ommatidium, in radians per second, the same layout

:func:fly_flow_from_directions returns.

Ground truth: for a rotation, `|f| = sin(angle(axis, d))` exactly, so it is

0 where the line of sight is along the axis and 1 where it is perpendicular;

and the flow is perpendicular to both the axis and the line of sight. For a

translation, `|f| = sin(angle)/depth` and the flow points away from the

direction of travel (the focus of expansion is where the template vanishes).

Raises `ValueError`: a malformed *lattice*, an *axis* that is not three

finite numbers or is zero-length, an unknown *motion*, and a non-positive

*depth_m*.

Ausführlicher Anwendungsleitfaden

• Leitfaden zur Familie fly_vision

Referenzen (Beispieldaten, Literatur)

• Katalog der Beispieldaten (Download-URLs / Lizenzen) — 2-D nutzt skimage.data (BSD/Public Domain) plus synthetische Bilder, 3-D nennt Download-URLs echter Datenquellen (Stanford, PDS, …).

• Herkunft und Literatur der Operatoren — die Quellen der Forschung/Verfahren, auf denen diese Operatorfamilie beruht.

• Der kanonische Algorithmus (Autor, Jahr) und seine Anwendungen stehen im Familienleitfaden oben.

Ausführbare Beispiele (verifizierte Samples, die diesen Operator wirklich aufrufen)

• poc_fly_optomotor_steering — py -3.11 examples/poc_fly_optomotor_steering.py

Typkompatible Folge-Operatoren (nehmen matrix als Eingabe)

fly_lamina_filter · fly_onoff_split · fly_t4t5_field · fly_flow_from_directions · fly_egomotion_from_flow · fly_hs_readout

Gleiche Kategorie (selfmotion)

fly_egomotion_from_flow · fly_eye_merge


*Provenance: flyvision.py — FLYVISION Operator-Registry. Diese Notiz wird von tools/opdocs.py md erzeugt (nicht von Hand bearbeiten).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.