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This study presented the results of the voice percussion expression experiment, and presented a voice percussion recognition method. The onomatopoeic expressions utilized in the regcognition experiment were extracted from the expression experiment. In the recognition experiment, the voice percussion recognition method achieved a recognition rate of 91.0% for the highest-tuned setting.
Voice percussion in our context is the mimicking of drum sounds by voice, expressed in verbal form that can be transcribed into phonemic representation, or onomatopoeia (e.g. don-tan-do-do-tan). Our paper describes a psychological experiment, voice percussion expression experiment, which gathers data on how subjects express drum patterns. This will serve as a preliminary basis for developing a voice percussion recognition method. Previous studies on query-by-humming focused on pitch detection and melodic feature extraction, but these features have less relevance in voice percussion recognition, which is primarily concerned with classification of timbre and identification of articulation methods. The methods for handling such features can be useful tools for music notation interface, and also can be applied to have promising applications in widening the scope of music information retrieval.
A "drum pattern" in our context means a sequence of drum beats that form minimum unit (one measure). In this thesis, drum patterns consist of only two percussion instruments . bass drum (BD) and snare drum (BD). In the expression experiment, there were 17 subjects of ages 19 to 31 (two with experience in percussion). The voice percussion sung by the subjects were recorded and analyzed. Significant discoveries from the expression experiment include: "the onomatopoeic expression had correspondence with the length and rhythmic patterns of the beats" and "some subjects may verbally expressed rest notes".
Our paper also describes a voice percussion recognition method. The voice percussion was compared with all the patterns in a drum pattern database, and the pattern that was estimated to be acoustically most close to the voice percussion is selected as the recognized result. The search first looks for drum patterns over onomatopoeic sequences. This selects instrument sequences with the highest likelihood ratings, which are then checked over their onset timings. The pattern with the highest ranking is output as the final result. The recognition method was tested by recognition experiments over a combination of different settings of the acoustic model and the pronunciation dictionary. The following 4 conditions were evaluated.
Following the encouraging results of the proposed method as a practical tool for voice percussion recognition, a score input interface, Voice Drummer, was developed, as its application. Voice Drummer consists of a score input mode which is used for drum pattern input intended for use in composition, and an arrangement mode which edits drum patterns in a given music piece. There is also a practice/adaptation mode where the user can practice and adapt the system to his/her voice, thus increasing the recognition rate.
This research utilized the RWC Music Database "RWC-MDB-P-2001" (Popular Music).