US 9,813,811 B1
Soundfield decomposition, reverberation reduction, and audio mixing of sub-soundfields at a video conference endpoint
Haohai Sun, Nesbru (NO)
Assigned to Cisco Technology, Inc., San Jose, CA (US)
Filed by Cisco Technology, Inc., San Jose, CA (US)
Filed on Jun. 1, 2016, as Appl. No. 15/170,495.
Int. Cl. H04B 3/20 (2006.01); H04R 3/00 (2006.01); H04R 29/00 (2006.01)
CPC H04R 3/005 (2013.01) [H04R 29/005 (2013.01); H04R 2410/01 (2013.01); H04R 2430/20 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
at a microphone array, detecting a soundfield to produce a set of microphone signals each from a corresponding microphone in the microphone array, the set of microphone signals representative of the soundfield;
decomposing the detected soundfield into a set of sub-soundfield signals based on the set of microphone signals, wherein the decomposing includes transforming each microphone signal to a corresponding frequency domain signal, to produce a set of frequency domain signals corresponding to the set of microphone signals, and applying a soundfield transformation matrix to the set of frequency domain signals to produce the set of sub-sound field signals;
processing each sub-soundfield signal, including dereverberating each sub-soundfield signal to remove reverberation therefrom, to produce a set of processed sub-soundfield signals; and
mixing the set of processed sub-sound field signals into a mixed output signal.