Title:
【発明の名称】少なくとも1個のコーダを有する伝送システム
Document Type and Number:
Japanese Patent JPH08501891
Kind Code:
A
Abstract:
PCT No. PCT/IB94/00007 Sec. 371 Date Jan. 5, 1995 Sec. 102(e) Date Jan. 5, 1995 PCT Filed May 2, 1994 PCT Pub. No. WO94/25961 PCT Pub. Date Nov. 10, 1994A coder/decoder for samples of speech or other audio signals with bit rate reduction includes an adaptive prediction filter having filter coefficients which are recursively computed according to the known Levinson-Durbin Recursion. Such computation is based on reflection coefficients derived from correlation coefficients applicable to segments of the audio signal samples, the reflection and prediction coefficients being in N-bit fixed point arithmetic. A kth reflection coefficient after its first computation is buffered with a minimum accuracy of N+1 bits, and the k-1 previously computed prediction coefficients are recomputed with a limitation of N bits. If overflow occurs, the buffered value is divided, e.g. by 2, after the re-computation is completed and then rounded to N bits. Since rounding occurs only after the new prediction coefficients are derived, the recursion achieves reduced error and is simpler to calculate.
Inventors:
HOFMANN RUDOLF (DE)
Application Number:
JP52407894A
Publication Date:
February 27, 1996
Filing Date:
May 02, 1994
Export Citation:
Assignee:
KONINKL PHILIPS ELECTRONICS NV (NL)
International Classes:
G01L9/14; G06F7/48; G10L13/00; G10L15/00; G10L19/06; H03H17/04; H03H21/00; H03M7/30; H04B14/06; G10L25/06; G10L25/90; (IPC1-7): G10L9/14; G10L9/18; H03M7/30; H04B14/06
Attorney, Agent or Firm:
Masao Sawada