发明名称 |
Frame erasure compensation method in a variable rate speech coder |
摘要 |
A frame erasure compensation method in a variable-rate speech coder includes quantizing, with a first encoder, a pitch lag value for a current frame and a first delta pitch lag value equal to the difference between the pitch lag value for the current frame and the pitch lag value for the previous frame. A second, predictive encoder quantizes only a second delta pitch lag value for the previous frame (equal to the difference between the pitch lag value for the previous frame and the pitch lag value for the frame prior to that frame). If the frame prior to the previous frame is processed as a frame erasure, the pitch lag value for the previous frame is obtained by subtracting the first delta pitch lag value from the pitch lag value for the current frame. The pitch lag value for the erasure frame is then obtained by subtracting the second delta pitch lag value from the pitch lag value for the previous frame. Additionally, a waveform interpolation method may be used to smooth discontinuities caused by changes in the coder pitch memory.
|
申请公布号 |
EP1850326(A2) |
申请公布日期 |
2007.10.31 |
申请号 |
EP20070013769 |
申请日期 |
2001.04.18 |
申请人 |
QUALCOMM, INCORPORATED |
发明人 |
MANJUNATH, SHARATH;HUANG, PENJUNG;CHOY, EDDIE-LUN, TIK |
分类号 |
G10L19/00;G10L19/04;G10L11/04;G10L13/00;G10L19/12;H03M7/36 |
主分类号 |
G10L19/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|