EP 0685836 B1 19990721 - Method and apparatus for preprocessing an acoustic signal before speech coding
Title (en)
Method and apparatus for preprocessing an acoustic signal before speech coding
Title (de)
Verfahren und Gerät zur Vorverarbeitung eines akustischen Signals vor der Sprachcodierung
Title (fr)
Procédé et dispositif de prétraitement d'un signal acoustique en amont d'un codeur de parole
Publication
Application
Priority
FR 9406824 A 19940603
Abstract (en)
[origin: EP0685836A1] The method involves input of an acoustic signal to a high pass filter. If the energy (E2) of the high-pass filter output exceeds a certain fraction of the energy (E1) of the unfiltered signal, a first state is selected. If it is less, a second state is selected where the signal is subjected to high frequency pre-emphasis. The modification does not occur if the filtered signal energy is less than a threshold. The state is changed if several successive signal frames indicate a state different to that previously determined. A counter (32) is incremented when a comparator (27) indicates a different state and is decremented towards zero when the same state is indicated. At a threshold value, the output state is changed and returns to zero. <IMAGE>
IPC 1-7
IPC 8 full level
G10L 19/06 (2013.01)
CPC (source: EP US)
G10L 19/06 (2013.01 - EP US)
Designated contracting state (EPC)
DE ES GB IT NL SE
DOCDB simple family (publication)
EP 0685836 A1 19951206; EP 0685836 B1 19990721; DE 69510865 D1 19990826; DE 69510865 T2 20000713; FR 2720849 A1 19951208; FR 2720849 B1 19960814; US 5644679 A 19970701
DOCDB simple family (application)
EP 95401261 A 19950531; DE 69510865 T 19950531; FR 9406824 A 19940603; US 46220995 A 19950605