Processing

Please wait...

Settings

Settings

Goto Application

1. WO2010031951 - PRE-ECHO ATTENUATION IN A DIGITAL AUDIO SIGNAL

Publication Number WO/2010/031951
Publication Date 25.03.2010
International Application No. PCT/FR2009/051724
International Filing Date 15.09.2009
IPC
G10L 19/14 2006.1
GPHYSICS
10MUSICAL INSTRUMENTS; ACOUSTICS
LSPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
19Speech or audio signal analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis
04using predictive techniques
14Details not provided for in groups G10L19/06-G10L19/1287
G10L 19/02 2006.1
GPHYSICS
10MUSICAL INSTRUMENTS; ACOUSTICS
LSPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
19Speech or audio signal analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis
02using spectral analysis, e.g. transform vocoders or subband vocoders
CPC
G10L 19/0212
GPHYSICS
10MUSICAL INSTRUMENTS; ACOUSTICS
LSPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
19Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis
02using spectral analysis, e.g. transform vocoders or subband vocoders
0212using orthogonal transformation
G10L 19/025
GPHYSICS
10MUSICAL INSTRUMENTS; ACOUSTICS
LSPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
19Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis
02using spectral analysis, e.g. transform vocoders or subband vocoders
022Blocking, i.e. grouping of samples in time; Choice of analysis windows; Overlap factoring
025Detection of transients or attacks for time/frequency resolution switching
G10L 19/26
GPHYSICS
10MUSICAL INSTRUMENTS; ACOUSTICS
LSPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
19Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis
04using predictive techniques
26Pre-filtering or post-filtering
Applicants
  • FRANCE TELECOM [FR]/[FR] (AllExceptUS)
  • KOVESI, Balazs [HU]/[FR] (UsOnly)
  • RAGOT, Stéphane [FR]/[FR] (UsOnly)
Inventors
  • KOVESI, Balazs
  • RAGOT, Stéphane
Agents
  • FRANCE TELECOM R&D/PIV/BREVETS
Priority Data
085624817.09.2008FR
Publication Language French (fr)
Filing Language French (FR)
Designated States
Title
(EN) PRE-ECHO ATTENUATION IN A DIGITAL AUDIO SIGNAL
(FR) ATTENUATION DE PRE-ECHOS DANS UN SIGNAL AUDIONUMERIQUE
Abstract
(EN) The invention relates to a method for attenuating pre-echoes in a digital audio signal generated from a transform encoding, wherein the method comprises, upon decoding and for a current frame of said digital audio signal, a step of defining (CONC) a concatenated signal from at least the reconstructed signal of the current frame, a step of dividing (DIV, 301) said concatenated signal into subunits of samples having a predetermined length, a step of calculating (ENV, 302) the time envelope of the concatenated signal, a step of detecting (DETECT, 304) the transition of the time envelope towards a high-energy area, a step of determining (DTECT, 304) the low-energy sub-units preceding a subunit in which a transition has been detected, and an attenuation step (ATT) in said determined subunits. The method is such that the attenuation is carried out according to an attenuation factor calculated for each of the determined subunits, based on the time envelope of the concatenated signal. The invention also relates to a device for implementing said method, and to a decoder including such a device.
(FR) L'invention porte sur un procédé d'atténuation de pré-échos dans un signal audionumérique engendré à partir d'un codage par transformée, dans lequel, au décodage, pour une trame courante de ce signal audionumérique, le procédé comporte une étape de définition (CONC) d'un signal concaténé, à partir au moins du signal reconstruit de la trame courante, une étape de division (DIV, 301) dudit signal concaténé en sous-blocs d'échantillons de longueur déterminée, une étape de calcul (ENV, 302) d'enveloppe temporelle du signal concaténé, une étape de détection (DETECT, 304) de transition de l'enveloppe temporelle vers une zone à forte énergie, une étape de détermination (DETECT, 304) des sous-blocs de basse énergie précédant un sous-bloc dans lequel une transition a été détectée et une étape d'atténuation (ATT) dans les sous-blocs déterminés. Le procédé est tel que l'atténuation s'effectue selon un facteur d'atténuation calculé pour chacun des sous- blocs déterminés, en fonction de l'enveloppe temporelle du signal concaténé. L'invention vise également un dispositif mettant en œuvre le procédé ainsi qu'un décodeur comportant un tel dispositif.
Related patent documents
RU2011115003This application is not viewable in PATENTSCOPE because the national phase entry has not been published yet or the national entry is issued from a country that does not share data with WIPO or there is a formatting issue or an unavailability of the application.
Latest bibliographic data on file with the International Bureau