| 摘要 |
<P>PROBLEM TO BE SOLVED: To make analyzable a stationary portion of musical sound other than a fluctuating portion, i.e., a portion equivalent to one note even though pitch or level of inputted sound from a microphone or the like is delicately fluctuated. <P>SOLUTION: Arbitrary sound signals are inputted and a filtering process having a prescribed frequency characteristic is conducted for the sound signals. Then, an analysis is performed to determine the degree of agreement between adjacent waveforms based on continuously sampled amplitude values of the sound signals after the filtering process. A segment, which is made of a plurality of waveforms that are analyzed and determined to be agreed with each other within a range following a prescribed condition in the analysis result, is detected as a same waveform segment and the pitch of the sound signals in the detected same waveform segment is detected. In the same waveform segment, the pitch of the inputted sound signals is stable and the segment is suitable as the objective segment of a pitch detection process. Thus, appropriate pitch detection of the inputted sound signals can be accurately and easily conducted. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
