Human beatbox sound recognition using an automatic speech recognition toolkit

Abstract

Human beatboxing is a vocal art making use of speech organs to produce percussive sounds and imitate musical instruments. Beatbox sound classification is a current challenge that can be used for automatic database annotation and music-information retrieval. In this study, a human-beatbox sound recognition system was developed with an adaptation of the Kaldi toolbox. Such tool is already widely used for automatic speech recognition. The corpus consisted of eighty boxemes, which were recorded repeatedly by two beatboxers. The sounds were annotated and transcribed to the system by means of a beatbox-specific pictographic writing (Vocal Grammatics). The recognition-system robustness to recording conditions was assessed on recordings of six different microphones and settings. The decoding part was made with monophone acoustic models trained with a classical HMM-GMM model. Different parameters of our system were tested : i) the number of HMM states, ii) the number of MFCC, iii) the presence or not of a pause boxeme in right and left contexts in the lexicon and iv) the rate of silence probability. Our best model was obtained with the addition of a pause in left and right contexts of each boxeme in the lexicon, a 0.8 silence probability, 22 MFCC and three states HMM. Boxeme error rate in such configuration was lowered to 15.13%.

Speech and beatboxing cooperate and compromise in beatrhyming

“…A few scholars have suggested phonological analogies for beatboxing sound organization. Evain et al (2019) and Paroni et al (2021a,b) posit the existence of a "boxeme" by analogy to the phoneme-an acoustically and articulatorily distinct building block of a beatboxing sequence. Separately, Guinn and Nazarov (2018) argue for sub-segmental features in beatboxing based on evidence from variations in beat patterns and phonotactic place restrictions (an absence of beatboxing coronals in prominent metrical positions), though they do not link features back to larger segment-sized units.…”