ambiscape
Analysis toolkit for long-duration first-order ambisonic soundscape recordings — hours to whole nights of AmbiX B-format audio from recorders like the Zoom H3-VR, processed in a stream with constant memory.
Why
Most audio analysis tooling assumes a file you can load whole. Long-form field recording produces something else: tens of gigabytes per session, split into 2 GB files by the recorder, in which the interesting structure lives at time scales of minutes to hours — machine duty cycles, diurnal traffic envelopes, day/night state changes. ambiscape treats the session (a folder of WAVs on one absolute clock) as its unit of analysis and produces:
- descriptors in the environmental-acoustics idiom (Leq, LAeq, L10/L50/L90, event statistics),
- spatial timelines only ambisonics can supply — direction of arrival, diffuseness, azimuthal concentration,
- figures (session overview, percentile spectra, directograms, taxonomy maps and timelines),
- room acoustics (T60 from claps or incidental impulses),
- machine states — on/off segmentation, duty cycles, source spectral fingerprints, and targeted civic-grid scans (church clocks, sirens),
- mains hum / ENF — millihertz tracking of the electric network frequency for grid forensics and hum characterization,
- ratings & global indices — NR/NC/RC room criteria, intermittency ratio and emergence, the ecoacoustic battery (ACI, ADI/AEI, NDSI, BI, H), EDT/C50/C80/D50, and spatial descriptors (directional entropy, horizon fractions, foreground/background direction overlap),
- biophony — structural measures of nature/animal sound (narrowband activity, temporal entropy, spatial dispersion) plus an optional BirdNET species layer gated to hi-fi windows,
- strike-level rhythm of quasi-periodic sources — bells, machines — with periodicity, phase, and repetition-vs-variation statistics,
- ISO 12913-3 psychoacoustic indicators and a calibration hook,
- machine-listening assists (AudioSet tagging, a speech privacy gate),
- publication exports (non-identifying 1 Hz features; curated segment selection),
- corpus aggregation — one cross-session table (CSV + Markdown) from every session's cached summary, with ranking and outlier queries.
Relationship to ambiviz
ambiscape is the streaming companion to ambiviz. ambiviz renders rich spatial visuals (AEM spherical energy maps, anglegrams, directograms) from audio it can load whole; ambiscape summarizes recordings too long for that, and selects the short representative excerpts that ambiviz then visualizes in detail. Plot names and conventions follow ambiviz where the two overlap.