Uniform and warped low delay filter-banks for speech enhancement

Uniform and warped low delay filter-banks for speech enhancement

A versatile filter-bank concept for adaptive subband filtering is proposed, which achieves a significantly lower algorithmic signal delay than commonly used analysissynthesis filter-banks. It is derived as an efficient implementation of the filter-bank summation method and performs time-domain filtering with coefficients adapted in the uniform or non-uniform frequency-domain. The frequency warp...

Low Delay Filter-Banks for Speech and Audio Processing

Eecient Low Delay Filter Banks

This paper treats the problem of designing eecient FIR analysis-synthesis lter banks with system delays that can be pre-speciied. A framework is introduced that is comprised of the cascade of several distinctive matrices with invertibility properties. The explicit form of the matrices guarantees computational ee-ciency and exact reconstruction, and allows for control over the system delay.

Time-Varying Filter Banks with Low Delay for Audio Coding

A design method and filter structure for fast modulated low delay filter banks is presented. The system delay can be pre-specified independent of the filter length. Perfect reconstruction is structurally guaranteed. It is shown how to make this structure time-varying, which includes switching the number of bands, while maintaining perfect reconstruction. Low delay filter banks, besides having t...

Low Delay SBR Filter Banks for MPEG-4 AAC- ELD

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...