A key computational principle for encoding time-varying signals in auditory and somatosensory cortices of monkeys is the opponent model of rate coding by two distinct populations of neurons. However, the subthreshold mechanisms that give rise to this computation have not been revealed. Because the rate-coding neurons are only observed in awake conditions, it is especially challenging to probe t...

Many applications in auditory modeling require analysis filters that approximate the frequency selectivity given by psychophysical data, e.g. from masking experiments using narrow-band maskers. This frequency selectivity is largely determined by the spectral decomposition process inside the human cochlea. Currently used spectral decomposition schemes for masking modeling in audio coding general...

Subband coding is becoming a viable compression method for video transmission, since the subband system can be eeciently split into a base layer and an enhancement layer without incurring any overhead. This is desirable in ATM and other packet networks. The base layer can be a standard coding algorithm such as H.261 or MPEG. In a subband-based video coding system, the higher-frequency subbands ...

This paper proposes an e cient rate scalable low complexity audio coder based on the SPIHT set partitioning in hierarchical trees coding algorithm which has achieved notable success in still image coding A wavelet packet transform is used to decompose the audio signal into frequency subbands corresponding roughly to the critical subbands of the human auditory system A psychoacustic model which ...

This paper proposes an eecient, rate-scalable, low complexity audio coder based on the SPIHT (set partitioning in hierarchical trees) coding algorithm 5], which has achieved notable success in still image coding. A wavelet packet transform is used to decompose the audio signal into 29 frequency subbands corresponding roughly to the critical subbands of the human auditory system. A psychoacustic...

The combination of CDMA and space time block coding (STBC) has been proposed for indoor environment where the delay spreads are very small and the channel is flat fading. However, these schemes are not valid for the outdoor situation where the delay spreads are significantly large and the channel is frequency selective fading. Therefore, in our paper, we propose CDMA with space-time block codin...

In this letter, a switched transmission technique is presented that can provide the orthogonal frequency division multiplexing (OFDM) systems with additional diversity gain. The space-time block coding (STBC) and space-frequency block coding (SFBC) are considered for the transmission of the OFDM signals. A proper coding scheme is selected based on the estimated normalized delay spread and norma...

This paper proposes an eecient, low complexity audio coder based on the SPIHT (set partitioning in hierarchical trees) coding algorithm 5], which has achieved notable success in still image coding. A wavelet packet transform is used to decompose the audio signal into 29 frequency subbands corresponding roughly to the critical subbands of the human auditory system. A psychoacustic model ,which, ...

MPEG-4 standardizes natural audio coding at bitrates ranging from 2 kbit/s, suitable for intelligible speech coding, to 64 kbitls per channel, suitable for high-quality audio coding. Within this range, three categories of coding are defined: parametric coding, Code Excited Linear Predictive coding (CELP) and time/frequency (T/F) coding. The unique contribution of MPEG4 audio is that not only do...