Spectral Noise Gate Technique Applied to Birdsong Preprocessing on Embedded Unit

Abstract

This paper proposes an approach for audio preprocessing and noise removal from recordings obtained in natural environments. The method is inspired in the acoustic signature of the audio, and aims to preprocess the recordings of bird songs obtained directly in the field. Using the Spectral Noise Gate technique, the undesired noise is removed on a real application in real time during the recording using an embedded environment. In addition, important statistic features of the audio signal are computed. The main purpose on approach is to eliminate the manual and tedious process of preparing the audio recordings done in the field in order to make them ready to be used as input in other tasks, such as the automatic classification of bird species from recorded bird songs. This is necessary because classification results depend widely from the quality of the input data.