| 摘要 |
PCT No. PCT/FR96/00006 Sec. 371 Date Oct. 22, 1997 Sec. 102(e) Date Oct. 22, 1997 PCT Filed Jan. 3, 1996 PCT Pub. No. WO96/21220 PCT Pub. Date Jul. 11, 1996A linear prediction analysis is performed for each frame of a speech signal to determine the coefficients of a short-term synthesis filter and an open-loop analysis is performed to determine a degree of frame voicing. At least one closed-loop analysis is performed for each sub-frame to determine an excitation sequence which, when applied to the short-term synthesis filter, generates a synthetic signal representative of the speech signal. Each closed-loop analysis uses the impulse response of a filter consisting of the short-term synthesis filter and a perceptual weighting filter, by truncating the impulse response to a truncation length that is no greater than the number of samples per sub-frame and is dependent on the energy distribution of the response and the degree of voicing of the frame. |
