知的採譜システム

抄録

Transcription is the process to make a score from sound. It is necessary in musicology field and also one of the interesting targets as application of AI. In the transcription system, the techniques of both of signal processing and symbol processing are required. Most of previous works have been devoted to the transcription for monophony, because of the difficulty of frequency separation in signal processing. We have developed a sophisticated peak frequency extraction method called "Interpolation method in complex spectra", which solved the problem of frequency separation. But it also made us find that the most difficult problem in transcription lay in symbol processing. The system has to know what is music to be transcribed. This paper describes a new transcription system for polyphonic sound based on the musical constraints. The process to extract notes from sound and the process to make score from notes are discussed in this paper. In the former step, the system uses the tonal model and the beat tracer. In the latter step, the system uses the knowledge of musical structure. We made some experiments for piano, guitar and shamisen. Experimental results show that the system can transcribe music of the instruments whose tonal attack is clear and that it is effective for popular light music.