fly_onoff_split — FLYVISION `lamina` op

• データ種: matrix → matrix

• 呼び出し: import fullseye as fs; fs.ledger.fly_onoff_split(movie, dt_s, tau_on_s=0.02, tau_off_s=0.02, rectify=True) (実装を直接呼ぶなら import flyvision; flyvision.fly_onoff_split(movie, dt_s, tau_on_s=0.02, tau_off_s=0.02, rectify=True)、台帳から引くなら opsflyvision.get("fly_onoff_split"))

使い方

Split a contrast movie into the ON and OFF channels the medulla carries.

Beyond the lamina the fly stops carrying one signed signal and carries two:

an ON channel (Mi1 / Tm3, brightening) and an OFF channel (Tm1 / Tm2, darkening), each with its own relay dynamics. This op is that split, and it keeps the rectification *optional* on purpose: the split was measured downstream, in the motion response (Joesch et al., *Nature* 468:300, 2010), while L1/L2 themselves respond linearly (Clark et al., *Neuron* 70:1165, 2011), so a pathway that rectifies at the lamina is making a claim the recordings do not.

movie: (T, n) contrast, rows = time (the return of fly_lamina_filter). dt_s: sample interval, seconds. tau_on_s / tau_off_s: the low-pass time constant of each channel, seconds.

rectify: True half-wave rectifies (ON = max(c, 0), OFF = max(-c, 0), both >= 0); False passes the signed contrast into the ON channel and its negation into the OFF channel, which is the linear L1/L2 case and lets the rectification happen downstream instead.

Returns (T, 2n) float64: columns 0..n-1 are ON, n..2n-1 are OFF, the same ommatidium order in each half.

Ground truth (exact, with tau_on_s == tau_off_s so the two channels share one filter):

• ON - OFF is the low-passed input, whichever *rectify* you chose;

• with rectify=True, ON + OFF is the low-passed absolute value;

• a movie that never goes negative leaves the OFF channel identically zero (and vice versa) — the split does not invent a dark event.

Raises ValueError: a non-2-D / too-short / non-finite *movie*, a movie

over MAX_MOVIE_ELEMENTS, and a non-positive *dt_s* / *tau_on_s* / *tau_off_s*.

詳しい使い方ガイド

• fly_vision ファミリガイド

参考(サンプルデータ・文献)

• サンプルデータカタログ(DL URL / ライセンス) — 2-D は skimage.data(BSD/public)+ 合成、3-D は実データ源(Stanford/PDS 等)の DL URL。

• 演算子の来歴・参考文献 — この op 族の元になった研究/手法の出典。

• アルゴリズムの正典(著者・年)と用途は上記ファミリ使い方ガイドに記載。

実行できる例(この op を実際に呼ぶ検証済みサンプル)

• poc_fly_optomotor_steering — py -3.11 examples/poc_fly_optomotor_steering.py

型が繋がる次の op(`matrix` を入力に取れる)

fly_lamina_filter · fly_t4t5_field · fly_flow_from_directions · fly_egomotion_from_flow · fly_hs_readout

同カテゴリ(`lamina`)

fly_lamina_filter

*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)。*

fly_onoff_split — FLYVISION lamina op

使い方