发明名称 |
Speech mode based multi-stage vector quantizer |
摘要 |
A speech mode based multi-stage vector quantizer is disclosed which quantizes and encodes line spectral frequency (LSF) vectors that were obtained by transforming the short-term predictor filter coefficients in a speech codec that utilizes linear predictive techniques. The quantizer includes a mode classifier that classifies each speech frame of a speech signal as being associated with one of a voiced, spectrally stationary (Mode A) speech frame, a voiced, spectrally non-stationary (Mode B) speech frame and an unvoiced (Mode C) speech frame. A converter converts each speech frame of the speech signal into an LSF vector and an LSF vector quantizer includes a 12-bit, two-stage, backward predictive vector encoder that encodes the Mode A speech frames and a 22 bit, four-stage backward predictive vector encoder that encodes the Mode 13 and the Mode C speech frames.
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申请公布号 |
US5966688(A) |
申请公布日期 |
1999.10.12 |
申请号 |
US19970958143 |
申请日期 |
1997.10.28 |
申请人 |
HUGHES ELECTRONICS CORPORATION |
发明人 |
NANDKUMAR, SRINIVAS;SWAMINATHAN, KUMAR |
分类号 |
G10L11/06;G10L19/00;G10L19/06;(IPC1-7):G10L3/02 |
主分类号 |
G10L11/06 |
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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