US 11,810,582 B2
MDCT-based complex prediction stereo coding
Heiko Purnhagen, Sundbyberg (SE); Pontus Carlsson, Bromma (SE); and Lars Villemoes, Järfälla (SE)
Assigned to DOLBY INTERNATIONAL AB, Dublin (IE)
Filed by DOLBY INTERNATIONAL AB, Amsterdam Zuidoost (NL)
Filed on Dec. 23, 2021, as Appl. No. 17/560,295.
Application 14/793,297 is a division of application No. 13/638,898, granted, now 9,111,530, issued on Aug. 18, 2015, previously published as PCT/EP2011/055350, filed on Apr. 6, 2011.
Application 17/560,295 is a continuation of application No. 16/931,377, filed on Jul. 16, 2020, granted, now 11,217,259.
Application 16/931,377 is a continuation of application No. 16/593,235, filed on Oct. 4, 2019, granted, now 10,734,002, issued on Aug. 4, 2020.
Application 16/593,235 is a continuation of application No. 16/427,735, filed on May 31, 2019, granted, now 10,475,459, issued on Nov. 12, 2019.
Application 16/427,735 is a continuation of application No. 16/222,721, filed on Dec. 17, 2018, granted, now 10,360,920, issued on Jul. 23, 2019.
Application 16/222,721 is a continuation of application No. 15/849,622, filed on Dec. 20, 2017, granted, now 10,283,126, issued on May 7, 2019.
Application 15/849,622 is a continuation of application No. 14/793,297, filed on Jul. 7, 2015, granted, now 9,892,736, issued on Feb. 13, 2018.
Claims priority of provisional application 61/322,458, filed on Apr. 9, 2010.
Prior Publication US 2022/0180876 A1, Jun. 9, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. G10L 19/008 (2013.01); G10L 19/06 (2013.01); G10L 19/18 (2013.01); H04S 3/00 (2006.01); G10L 19/02 (2013.01); G10L 19/16 (2013.01); G10L 25/12 (2013.01)
CPC G10L 19/008 (2013.01) [G10L 19/0212 (2013.01); G10L 19/06 (2013.01); G10L 19/167 (2013.01); G10L 19/18 (2013.01); H04S 3/008 (2013.01); G10L 25/12 (2013.01); H04S 2400/01 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A decoder system for providing a stereo signal by complex prediction stereo decoding, the decoder system comprising:
an upmix stage adapted to generate the stereo signal based on first frequency-domain representations of a downmix signal and a residual signal, each of the first frequency-domain representations comprising first spectral components representing spectral content of the corresponding signal expressed in a first subspace of a multidimensional space, the upmix stage comprising:
a module for computing a second frequency-domain representation of the downmix signal based on the first frequency-domain representation of the downmix signal, the second frequency-domain representation comprising second spectral components representing spectral content of the downmix signal expressed in a second subspace of the multidimensional space that includes a portion of the multidimensional space not included in the first subspace;
a weighted summer for computing a side signal by combining the first frequency-domain representation of the residual signal, the first frequency-domain representation of the downmix signal weighted by a real-valued part of a complex prediction coefficient, and the second frequency-domain representation of the downmix signal weighted by an imaginary-valued part of the complex prediction coefficient; and
a sum-and-difference stage for computing the stereo signal based on the first frequency-domain representation of the downmix signal and the side signal;
a first frequency-domain modifier stage arranged upstream of the upmix stage and operable in an active mode, in which it processes a frequency-domain representation of at least one signal, and a passive mode, in which it acts as a pass-through; and
a second frequency-domain modifier stage arranged downstream of the upmix stage and operable in an active mode, in which it processes a frequency-domain representation of at least one signal, and a passive mode, in which it acts as a pass-through.