US 9,812,140 B2
Method and apparatus for quadrature mirror filtering
Kang-eun Lee, Hwaseong-si (KR); Do-hyung Kim, Hwaseong-si (KR); Chang-yong Son, Gunpo-si (KR); Si-hwa Lee, Seoul (KR); and Seok-hwan Jo, Suwon-si (KR)
Assigned to SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed by SAMSUNG ELECTRONICS CO., LTD., Suwon-si, Gyeonggi-do (KR)
Filed on Oct. 27, 2014, as Appl. No. 14/524,306.
Claims priority of application No. 10-2013-0128645 (KR), filed on Oct. 28, 2013.
Prior Publication US 2015/0120306 A1, Apr. 30, 2015
Int. Cl. G10L 19/00 (2013.01); G10L 19/02 (2013.01); G06F 9/355 (2006.01); H03H 17/02 (2006.01)
CPC G10L 19/0204 (2013.01) [G06F 9/3552 (2013.01); H03H 17/0272 (2013.01)] 14 Claims
OG exemplary drawing
1. A method of performing quadrature mirror filter (QMF) synthesis filtering, the method comprising:
determining, by a modulator, positions of samples to be discarded from a first memory bank that comprises modulated QMF sub-band samples by performing a first modulo operation based on sample recording positions in a previous time slot;
recording, by the modulator, at the determined positions, samples corresponding to a current time slot by replacing the samples recorded at the determined positions in the previous time slot with the samples corresponding to the current time slot;
extracting, by a synthesis filter comprising at least one processor, samples from the first memory bank, wherein positions of the samples to be extracted are determined according to whether the current time slot is an even number or an odd number;
determining, by the synthesis filter, filter coefficients corresponding to the extracted samples by performing a second modulo operation, according to the current time slot; and
obtaining, by the synthesis filter, a time domain sample by accumulating results of multiplications of the extracted samples and the determined filter coefficients.