Global Patent Index - EP 2456236 A1

EP 2456236 A1 20120523 - Constrained filter encoding of polyphonic signals

Title (en)

Constrained filter encoding of polyphonic signals

Title (de)

Eingeschränkte Filtercodierung polyphoner Signale

Title (fr)

Codage sur filtre en mode contraint pour signaux polyphoniques

Publication

EP 2456236 A1 20120523 (EN)

Application

EP 12154099 A 20041215

Priority

  • EP 04809080 A 20041215
  • SE 0303499 A 20031219
  • SE 0400415 A 20040220

Abstract (en)

Signals of different channels (c 1 -c N ) are combined into one mono signal (x). A set of adaptive filters, preferably one for each channel (c 1 -c N ), is derived in a respective filter adaptation unit (30:1-30:N). When an adaptive filter is applied to the mono signal (x) it reconstructs the signal of the respective channel (c 1 -c N ) under a perceptual constraint. The perceptual constraint is a gain and/or shape constraint. The gain constraint allows the preservation of the relative energy between the channels (c 1 -c N ) while the shape constraint allows more stability by avoiding unnecessary filtering of spectral nulls. The transmitted parameters are the mono signal (x), in encoded form, and the parameters (p 1 -p N ) of the adaptive filters, preferably also encoded. The receiver reconstructs the signal of the different channels by applying the adaptive filters and possibly some additional post-processing.

IPC 8 full level

H04S 5/02 (2006.01); G10L 19/008 (2013.01)

IPC 8 main group level

H04B (2006.01)

CPC (source: EP SE)

G10L 19/008 (2013.01 - SE); H04S 5/02 (2013.01 - EP); G10L 19/008 (2013.01 - EP)

Citation (applicant)

Citation (search report)

  • [A] EP 0559383 A1 19930908 - AMERICAN TELEPHONE & TELEGRAPH [US]
  • [X] HERRE J ET AL: "INTENSITY STEREO CODING", PREPRINTS OF PAPERS PRESENTED AT THE AES CONVENTION, XX, XX, vol. 96, no. 3799, 26 February 1994 (1994-02-26), pages 1 - 10, XP009025131
  • [A] FALLER C ET AL: "Efficient representation of spatial audio using perceptual parametrization", IEEE WORKSHOP ON APPLICATIONS OF SIGNAL PROCESSING TO AUDIOAND ACOUSTICS, XX, XX, 21 October 2001 (2001-10-21), pages 199 - 202, XP002245584

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU MC NL PL PT RO SE SI SK TR

DOCDB simple family (publication)

WO 2005059901 A1 20050630; DK 1639580 T3 20140113; EP 1639580 A1 20060329; EP 1639580 B1 20131023; EP 2456236 A1 20120523; ES 2439693 T3 20140124; JP 2007527543 A 20070927; JP 4323520 B2 20090902; PL 1639580 T3 20140430; PT 1639580 E 20131119; SE 0400415 D0 20040220; SE 0400415 L 20050620; SE 527713 C2 20060523

DOCDB simple family (application)

SE 2004001907 W 20041215; DK 04809080 T 20041215; EP 04809080 A 20041215; EP 12154099 A 20041215; ES 04809080 T 20041215; JP 2006518597 A 20041215; PL 04809080 T 20041215; PT 04809080 T 20041215; SE 0400415 A 20040220