EP 1259957 A1 20021127 - CLOSED-LOOP MULTIMODE MIXED-DOMAIN SPEECH CODER
Title (en)
CLOSED-LOOP MULTIMODE MIXED-DOMAIN SPEECH CODER
Title (de)
MULTIMODALER MISCHBEREICH-SPRACHKODIERER MIT GESCHLOSSENER REGELSCHLEIFE
Title (fr)
CODEUR VOCAL MULTIMODE A DOMAINE MIXTE ET EN BOUCLE FERMEE
Publication
Application
Priority
US 0005140 W 20000229
Abstract (en)
[origin: WO0165544A1] A closed-loop, multimode, mixed-domain linear prediction (MDLP) speech coder includes a high-rate, time-domain coding mode, a low-rate, frequency-domain coding mode, and a closed-loop mode-selection mechanism for selecting a coding mode for the coder based upon the speech content of frames input to the coder. Transition speech (i.e., from unvoiced speech to voiced speech, or vice versa) frames are encoded with the high-rate, time-domain coding mode, which may be a CELP coding mode. Voiced speech frames are encoded with the low-rate, frequency-domain coding mode, which may be a harmonic coding mode. Phase parameters are not encoded by the frequency-domain coding mode, and are instead modeled in accordance with, e.g., a quadratic phase model. For each speech frame encoded with the frequency-domain coding mode, the initial phase value is taken to be the initial phase value of the immediately preceding speech frame encoded with the frequency-domain coding mode. If the immediately preceding speech frame was encoded with the time-domain coding mode, the initial phase value of the current speech frame is computed from the decoded speech frame information of the immediately preceding, time-domain-encoded speech frame. Each speech frame encoded with the frequency-domain coding mode may be compared with the corresponding input speech frame to obtain a performance measure. If the performance measure falls below a predefined threshold value, the input speech frame is encoded with the time-domain coding mode.
IPC 1-7
IPC 8 full level
G10L 19/18 (2013.01); G10L 19/00 (2013.01); H03M 7/36 (2006.01)
CPC (source: EP KR)
G10L 19/00 (2013.01 - KR); G10L 19/18 (2013.01 - EP KR)
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)
WO 0165544 A1 20010907; AT E341074 T1 20061015; AU 3385100 A 20010912; CN 1266674 C 20060726; CN 1437747 A 20030820; DE 60031002 D1 20061109; DE 60031002 T2 20070510; EP 1259957 A1 20021127; EP 1259957 B1 20060927; ES 2269112 T3 20070401; HK 1055833 A1 20040121; JP 2003525473 A 20030826; JP 4907826 B2 20120404; KR 100711047 B1 20070424; KR 20020081374 A 20021026
DOCDB simple family (application)
US 0005140 W 20000229; AT 00912053 T 20000229; AU 3385100 A 20000229; CN 00819221 A 20000229; DE 60031002 T 20000229; EP 00912053 A 20000229; ES 00912053 T 20000229; HK 03108074 A 20031107; JP 2001564148 A 20000229; KR 20027011306 A 20020828