find_events: Wrapper to call bioacoustics::threshold_detection

In mottensmann/NocMigR: A Suite of Functions to Play with NocMig and Other Long-Term Recordings

Wrapper to call bioacoustics::threshold_detection

Description

Queries bioacoustics::threshold_detection to detect events in a audio file and exports labels to explore the file in audacity

Usage

find_events(
  wav.file = NULL,
  overwrite = TRUE,
  threshold = 10,
  min_dur = 10,
  max_dur = 5000,
  min_TBE = 40,
  max_TBE = Inf,
  LPF = 15000,
  HPF = 80,
  FFT_size = 1024,
  start_thr = 20,
  end_thr = 48,
  SNR_thr = 4,
  angle_thr = 125,
  NWS = 1500,
  time_scale = 2,
  ...
)

Arguments

wav.file	Audio file. Currently supported are WAV or MP3 files.
overwrite	logical
threshold	integer. Sensitivity of the audio event detection function (peak-picking algorithm) in dB. A threshold value of 14 dB above SNR is recommended. Higher values increase the risk of leaving audio events undetected (false negative). In a noisy recording (low SNR) this sensitivity threshold may be set at 12 dB, but a value below 10 dB is not recommended. Default setting is 14 dB above SNR.
min_dur	numeric. Minimum duration threshold in milliseconds (ms). Extracted audio events shorter than this threshold are ignored. Default setting is 1.5 ms.
max_dur	numeric. Maximum duration threshold in milliseconds (ms). Extracted audio events longer than this threshold are ignored. The default setting is 80 ms.
min_TBE	numeric. Minimum time window between two audio events in milliseconds (ms). If the time interval between two successive audio events is shorter than this window, they are ignored. The default setting is 20 ms.
max_TBE	numeric. Maximum time window between two audio events in milliseconds (ms). If the time interval between two successive audio events is longer than this window, they are ignored. The default setting is 1000 ms.
LPF	integer. Low-Pass Filter (Hz). Frequencies above the cutoff are greatly attenuated. Default is set internally at the Nyquist frequency of the recording.
HPF	integer. High-Pass Filter (Hz). Frequencies below the cutoff are greatly attenuated. Default setting is 16000 Hz. A default of 1000 Hz is recommended for most bird vocalizations.
FFT_size	integer. Size of the Fast Fourrier Transform (FFT) window. Default setting is 256.
start_thr	integer. Right to left amplitude threshold (dB) for audio event extraction, from the audio event centroid. The last FFT where the amplitude level is equal or above this threshold is considered the start of the audio event. Default setting is 40 dB. 20 dB is recommended for extracting bird vocalizations.
end_thr	integer. Left to right amplitude threshold (dB) for audio event extraction, from the audio event centroid. The last FFT where the amplitude level is equal or above this threshold is considered the end of the audio event. Default setting is 20 dB. 30 dB is recommended for extracting bird vocalizations.
SNR_thr	integer. SNR threshold (dB) at which the extraction of the audio event stops. Default setting is 10 dB. 8 dB is recommended for bird vocalizations.
angle_thr	integer. Angle threshold (°) at which the audio event extraction stops. Default setting is 40°. 125° is recommended for extracting bird vocalizations.
NWS	integer. Length of the time window used for background noise estimation in the recording (ms). A longer window size is less sensitive to local variations in the background noise. Default setting is 100 ms.
time_scale	numeric. Time resolution of the spectrogram in milliseconds (ms) per pixel (px). Default setting is 0.1 ms for bat echolocation calls. A default of 2 ms/px is recommended for most bird vocalizations.
...	Not yet implemented! optional arguments passed on to threshold_detection.

Value

list (see threshold_detection)

mottensmann/NocMigR documentation built on Oct. 3, 2023, 3:36 a.m.