Low Delay SBR Filter Banks for MPEG-4 AAC- ELD
نویسندگان
چکیده
MPEG’s low-delay audio codecs AAC-LD and AACELD are capable of providing natural audio in perceptually high quality with an algorithmic system delay1 in the range from 20 to 46.9 mS. The AAC-ELD scheme, in particular, which is basically formed out of AAC-LD and SBR, produces high-quality wideband audio at bit rates between 24 kbps and 48 kbps maintaining a relatively low algorithmic delay of 31.3 ms, where 1.3 ms are due to SBR, at 48 kHz sampling rate. These are three crucial factors for AAC-ELD to conquer the telecommunications sector. Keywords–Advanced audio coding(AAC),Discrete Cosine Transform (DCT); DCT-IV; factorization; fast algorithms; filter banks; low delay audio coding; Moving Picture Expert Group(MPEG); Spectral Band Replication (SBR)
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