EP 1212750 A1 20020612 - MULTIMODE VSELP SPEECH CODER
Title (en)
MULTIMODE VSELP SPEECH CODER
Title (de)
MULTIMODALER VSELP SPRACHKODIERER
Title (fr)
VOCODEUR DE TYPE VSELP
Publication
Application
Priority
- EP 0007566 W 20000802
- GB 9917916 A 19990802
Abstract (en)
[origin: GB2352949A] A speech coder 200 for a speech communications unit comprises means to analyse an incoming speech unit to determine a particular characteristic of the signal, e.g. pitch. A series of basis vectors is then generated by vector storage block 214 based on the determined characteristic. As described, sets of basis vectors are stored in sub-codebooks. A first sub-codebook models unvoiced speech, a second models voiced speech of pitch periods below a threshold and a third models voiced speech of pitch periods above the threshold. A phase synchroniser 228 is used to synchronise a phase of a present voiced speech signal to previous or perceived future speech signals. The excitation vectors u<SB>i</SB>(n) generated by the codebook generator 220 are processed by long and short term predictors 224,226 to give reconstructed speech vectors s'<SB>i</SB>(n) which are compared with the input speech vectors s(n), and the energy of the error signal is used by a codebook controller 240 to determined the code of the vector having the minimum error. This code I is output together with values of long and short term predictor parameters LTP,STP and excitation gain factor q .
IPC 1-7
IPC 8 full level
G10L 19/125 (2013.01)
CPC (source: EP)
G10L 19/125 (2013.01)
Citation (search report)
See references of WO 0109880A1
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
GB 2352949 A 20010207; GB 9917916 D0 19990929; AU 7272100 A 20010219; EP 1212750 A1 20020612; WO 0109880 A1 20010208
DOCDB simple family (application)
GB 9917916 A 19990802; AU 7272100 A 20000802; EP 0007566 W 20000802; EP 00960391 A 20000802