Polyspectral technique for the analysis of stress-waves characteristics and species recognition in wood veneers

In this work a simple technique to obtain information about the species of wood samples using stress-wave sounds in the audible range is presented. However, spectra of wood sounds generated by pendulum impact are very complex and feature extraction for classification purposes is very difficult. Polyspectral techniques have been successfully applied to several problems from radar pattern recognition to medical signal processing. Following this approach, convolution of four different sound impacts has been done. This permits to extract clear polyspectral features suitable for wood species recognition with possible applications to both human assisted and automatic wood identification systems with minimal intersample variability. Results indicate that using this technique only the two most intense polyspectral peaks are enough for species recognition.