Models

Acoustic model V2.4 - June 2023

• more than 6,000 species worldwide

• covers frequencies from 0 Hz to 15 kHz with two-channel spectrogram (one for low and one for high frequencies)

• 0.826 GFLOPs, 50.5 MB as FP32

• enhanced and optimized metadata model

• global selection of species (birds and non-birds) with 6,522 classes (incl. 11 non-event classes)

Technical details

• 48 kHz sampling rate (we up- and downsample automatically and can deal with artifacts from lower sampling rates)

• we compute 2 mel spectrograms as input for the convolutional neural network:

  • first one has fmin = 0 Hz and fmax = 3000; nfft = 2048; hop size = 278; 96 mel bins

  • second one has fmin = 500 Hz and fmax = 15 kHz; nfft = 1024; hop size = 280; 96 mel bins

• both spectrograms have a final resolution of 96x511 pixels

• raw audio will be normalized between -1 and 1 before spectrogram conversion

• we use non-linear magnitude scaling as mentioned in Schlüter 2018

• V2.4 uses an EfficienNetB0-like backbone with a final embedding size of 1024

• See this comment for more details

Geo model (species range model) V2.4 - V2, Jan 2024

• updated species range model based on eBird data

• more accurate (spatial) species range prediction

• slightly increased long-tail distribution in the temporal resolution

• see this discussion post for more details

Using older models

Older models are not supported in the current version of the package. If you need to use an older model, please refer to the BirdNET-Analyzer repository.