fullseye

fly_matched_filter — FLYVISION selfmotion op

使い方

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:

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.

詳しい使い方ガイド

参考(サンプルデータ・文献)

実行できる例(この op を実際に呼ぶ検証済みサンプル)

型が繋がる次の op(matrix を入力に取れる)

fly_lamina_filter · fly_onoff_split · fly_t4t5_field · fly_flow_from_directions · fly_egomotion_from_flow · fly_hs_readout

同カテゴリ(selfmotion)

fly_egomotion_from_flow · fly_eye_merge


Provenance: flyvision.py — FLYVISION operator registry. この per-op ノートは tools/opdocs.py md が自動生成(手編集しない)。

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