fullseye

percentile_level — ACOUSTICS level op

使い方

Statistical levels: L_N is the level exceeded N % of the time.

The record is cut into non-overlapping blocks of window_s seconds, each block’s equivalent level is computed, and L_N is the (100-N)-th percentile of those levels. Non-overlapping rectangular blocks are used rather than an exponential time weighting because the block length is then exactly what the caller asked for and the statistic is exactly a percentile of the returned levels array — an exponential average would make the effective averaging time a function of the signal.

Returns a dict with one key per requested percentile ("L10", "L50", "L90", formatted with %g), plus levels (the per-block levels), times (block start times, s), n_blocks, block_samples, leq (the energy-equivalent level of the whole record), ref, weighting.

Note that L50 is the median level and leq is the energy level; they are different numbers whenever the signal is not stationary, and the gap between them is itself the usual measure of how fluctuating a record is.

Measured on a two-level test signal (1 s at 16 kHz, first half a 1 kHz sine of amplitude 1.0, second half the same at 0.1, Z-weighted, 0.125 s blocks, 8 blocks): L10 = -3.010300 and L90 = -23.010300 dB — exactly the two constituent levels, 20.000000 dB apart, as they must be for a 50/50 split. L50 = -13.010300 is the interpolated midpoint of the two clusters and leq = -5.977386, which is 17 dB above L90: the energy level sits near the loud half while the median sits between them. On a constant-amplitude signal all three percentiles and leq agree to 3.6e-15 dB.

Raises ValueError: everything :func:_as_signal refuses, a percentile outside [0, 100], a non-positive window_s, a window_s longer than the record (which would give one block and make every percentile the same number while still looking like a statistic), ref <= 0.

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(table を入力に取れる)

istft

同カテゴリ(level)

octave_bands · octave_spectrum · weighting_response · apply_weighting · equivalent_level


Provenance: acoustics.py — ACOUSTICS 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.