| 摘要 |
PURPOSE: To control the level, accent, etc., of a voice without lossing the naturality of voice by extending/shortening the pitch period of an waveform in a voiced sound section and continuously connecting the waveform. CONSTITUTION: An analysis part 2 extracts a voiced sound section from an A/D converted voice, obtains a linear prediction coefficient and a residual waveform by the linear prediction analysis of the voice waveform, determines one pitch section, and executes linear prediction analysis again by using an intersection point of the pitch section as the center of an analytical window. Then a pitch frequency control part 4 applies a required change to each of a series of pitch periods, newly calculates a pitch period string and extends/ shortens the waveform of each pitch corresponding to the new pitch period to adjust normalization power. An waveform connection part 6 compares speaking time length and continuously connects the waveform and a distortion correcting part 8 finds out the square sum of M sample data, calculates respective linear prediction coefficients, finds out a spectrum envelope, and obtains the envelope of the original sound. |
