发明名称 |
Selection of a synthesis filter for CELP type wideband audio coding |
摘要 |
In the CELP coding system a low-order synthesis filter and a cascade-connected synthesis filter formed by a cascade connection of low- and high-order synthesis filters are provided, a synthesized acoustic signal is estimated in a mode decision part for an input acoustic signal, and the estimated synthesized acoustic signal is subjected to inverse filtering by an inverse filter corresponding to the low-order synthesis filter and an inverse filter corresponding to the cascade-connected synthesis filter to obtain residual signals. That one of the synthesis filters which corresponds to the residual signal of smaller power is selected by a switch, and a codebook is searched for indices which will minimize the error between the output synthesized acoustic signal by the selected synthesis filter and the input acoustic signal. <IMAGE> |
申请公布号 |
EP1052622(B1) |
申请公布日期 |
2007.07.11 |
申请号 |
EP20000110124 |
申请日期 |
2000.05.10 |
申请人 |
NIPPON TELEGRAPH AND TELEPHONE CORPORATION |
发明人 |
SASAKI, SHIGEAKI;MANO, KAZUNORI;HAYASHI, SHINJI |
分类号 |
G10L19/06;G10L19/18 |
主分类号 |
G10L19/06 |
代理机构 |
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代理人 |
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地址 |
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