EP 1521242 A1 20050406 - Speech coding method applying noise reduction by modifying the codebook gain
Title (en)
Speech coding method applying noise reduction by modifying the codebook gain
Title (de)
Verfahren zur Sprachkodierung mit Geräuschunterdrückung durch Modifizierung der Kodebuchverstärkung
Title (fr)
Procédé de codage de la parole avec réduction de bruit au moyen de la modification du gain du livre de code
Publication
Application
Priority
EP 03022249 A 20031001
Abstract (en)
The invention refers to a method for encoding an acoustic signal (y(n)) containing a speech component and a noise component by using an analysis through synthesis method, wherein for encoding the acoustic signal a synthesised signal is compared with the acoustic signal for a time interval, said synthesised signal being described by using a fixed codebook and an associated fixed gain, comprising the steps: Extracting an estimated fixed gain (g/< ANd> n) of the noise component from the acoustic signal (y(n)) for the time interval; Representing the noise component for the time interval by its fixed gain (g/< ANd> n); Estimating a signal to noise ratio of the speech component to the noise component for the time interval based on the signal to noise ratio of an earlier time interval and a ratio of the acoustic signal (y(n)) to the noise component in the time interval; Determining a modification factor ( gamma c) based on the estimate of the signal to noise ratio; Deriving an estimate of a fixed gain (g/< ANd> s(m)) of the speech component by modifying said fixed gain of the speech component with a modification factor ( gamma c). <IMAGE>
IPC 1-7
IPC 8 full level
G10L 19/14 (2006.01); G10L 21/02 (2006.01); G10L 21/0208 (2013.01); G10L 19/00 (2006.01); G10L 21/0216 (2013.01); G10L 21/0232 (2013.01)
CPC (source: EP)
G10L 21/0208 (2013.01); G10L 21/0232 (2013.01); G10L 2021/02168 (2013.01)
Citation (search report)
- [Y] US 2002184010 A1 20021205 - ERIKSSON ANDERS [SE], et al
- [A] EP 1301018 A1 20030409 - CIT ALCATEL [FR]
- [A] WO 0102929 A2 20010111 - TELLABS OPERATIONS INC [US], et al
- [A] US 6026356 A 20000215 - YUE H S P [CA], et al
- [XY] CHANDRAN R ET AL: "COMPRESSED DOMAIN NOISE REDUCTION AND ECHO SUPPRESSION FOR NETWORK SPEECH ENHANCEMENT", PROCEEDINGS OF THE 43RD. IEEE MIDWEST SYMPOSIUM ON CIRCUITS AND SYSTEMS. MWSCAS 2000. LANSING, MI, NEW YORK, NY: IEEE, US, vol. 1 OF 3, 8 August 2000 (2000-08-08) - 11 August 2000 (2000-08-11), pages 10 - 13, XP002951730, ISBN: 0-7803-6476-7
- [A] MARTIN R ET AL: "Optimized estimation of spectral parameters for the coding of noisy speech", IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING, vol. 3, 5 June 2000 (2000-06-05), Istanbul, Turkey, pages 1479 - 1482, XP010507630
Designated contracting state (EPC)
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR
DOCDB simple family (publication)
DOCDB simple family (application)
EP 03022249 A 20031001; EP 2004051712 W 20040804