发明名称 |
Linear prediction coefficient generation during frame erasure or packet loss |
摘要 |
A speech coding system robust to frame erasure (or packet loss) is described. Illustrative embodiments are directed to a modified version of CCITT standard G.728. In the event of frame erasure, vectors of an excitation signal are synthesized based on previously stored excitation signal vectors generated during non-erased frames. This synthesis differs for voiced and non-voiced speech. During erased frames, linear prediction filter coefficients are synthesized as a weighted extrapolation of a set of linear prediction filter coefficients determined during non-erased frames. The weighting factor is a number less than 1. This weighting accomplishes a bandwidth-expansion of peaks in the frequency response of a linear predictive filter. Computational complexity during erased frames is reduced through the elimination of certain computations needed during non-erased frames only. This reduction in computational complexity offsets additional computation required for excitation signal synthesis and linear prediction filter coefficient generation during erased frames. |
申请公布号 |
AU1471395(A) |
申请公布日期 |
1995.09.21 |
申请号 |
AU19950014713 |
申请日期 |
1995.03.08 |
申请人 |
AT&T CORP. |
发明人 |
JUIN-HWEY CHEN;CRAIG ROBERT WATKINS |
分类号 |
G10L19/08;G10L19/00;G10L19/04;G10L19/06;G10L19/12;H03M7/30 |
主分类号 |
G10L19/08 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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