US 12,080,307 B2
Stereo audio encoder and decoder
Heiko Purnhagen, Sundbyberg (SE); and Kristofer Kjoerling, Solna (SE)
Assigned to DOLBY INTERNATIONAL AB, Dublin (IE)
Filed by DOLBY INTERNATIONAL AB, Dublin (IE)
Filed on Apr. 4, 2023, as Appl. No. 18/295,701.
Application 16/827,414 is a division of application No. 16/195,745, filed on Nov. 19, 2018, granted, now 10,600,429, issued on Mar. 24, 2020.
Application 18/295,701 is a continuation of application No. 16/827,414, filed on Mar. 23, 2020, granted, now 11,631,417.
Application 16/195,745 is a continuation of application No. 15/410,377, filed on Jan. 19, 2017, granted, now 10,163,449, issued on Dec. 25, 2018.
Application 15/410,377 is a continuation of application No. 14/781,712, granted, now 9,570,083, issued on Feb. 14, 2017, previously published as PCT/EP2014/056854, filed on Apr. 4, 2014.
Claims priority of provisional application 61/808,684, filed on Apr. 5, 2013.
Prior Publication US 2023/0245667 A1, Aug. 3, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04S 1/00 (2006.01); G10L 19/008 (2013.01); G10L 19/02 (2013.01); G10L 19/06 (2013.01); G10L 19/16 (2013.01); G10L 19/26 (2013.01); G10L 25/06 (2013.01)
CPC G10L 19/06 (2013.01) [G10L 19/008 (2013.01); G10L 19/02 (2013.01); G10L 19/0204 (2013.01); G10L 19/167 (2013.01); G10L 25/06 (2013.01); H04S 1/007 (2013.01); G10L 19/0212 (2013.01); G10L 19/265 (2013.01); H04S 2400/03 (2013.01); H04S 2420/03 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A method for decoding an encoded audio bitstream, the method comprising:
extracting from the encoded audio bitstream a first waveform-coded signal comprising of first spectral coefficients corresponding to frequencies up to a first cross-over frequency for a first time period;
extracting from the encoded audio bitstream a second waveform-coded signal comprising of second spectral coefficients corresponding to a subset of frequencies above the first cross-over frequency for the first time period, wherein the second waveform-coded signal does not comprise second spectral coefficients corresponding to frequencies up to the first cross-over frequency for the first time period;
extracting, from the encoded audio bitstream, reconstruction parameters;
determining, based on the second spectral coefficients, that the second waveform coded signal has a particular format; and
performing frequency reconstruction based on the particular format to extend the subset of frequencies above a second cross-over frequency to generate an extended signal for the first time period, wherein the second cross-over frequency is above the first cross-over frequency, wherein the frequency reconstruction uses the reconstruction parameters, and wherein the reconstruction parameters comprise a spectral envelope of the subset frequencies above the second cross-over frequency.