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DAU96 - Auditory model from Dau et. al. 1996.
Usage:
- [outsig, fc] = dau96(insig,fs,flow,fhigh);
- [outsig, fc] = dau96(insig,fs,flow,fhigh,basef);
Input parameters:
- insig: input acoustic signal.
- fs: sampling rate.
- flow: lowest filter center frequency.
- fhigh: highest filter center frequency.
- basef: Always include this frequency in the filter bank (optional).
Description:
DAU96(insig,fs,flow,fhigh) computes the internal representation of
the signal insig sampled with a frequency of fs Hz as described in Dau,
Puschel and Kohlrausch (1996a). The parameters flow and fhigh
determine the lowest and highest frequencies in the filter bank. The
filters are spaced 1 Erb apart
DAU96(insig,fs,flow,fhigh,basef) does the same, but ensures that the
frequency basef is one of the frequencies in the filter bank.
DAU96(insig,fs) chooses the lowest frequency to be 80 and the highest
to be 8000.
[outsig,fc]=DAU96(...) additionally returns the center frequencies of
the filter bank.
The model assumes than an input signal with an RMS value of 1
corresponds to an acoustic signal of 100 db SPL.
The dau96 model consists of the following stages:
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a gammatone filter bank with 1
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an envelope extraction stage done by half
followed by low-pass filtering to 1000 Hz.
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an adaptation stage modelling nerve adaptation by a cascade of 5
loops.
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a modulation low pass filter liming modulations to below 50 Hz.
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The model implemented in this file is not identical to the model
published in Dau et. al. (1996a). An overshoot limit has been added to
the adaptation stage to fix a problem where abrupt changes in the
input signal would cause unnaturally big responses. This is described
in Dau et. al. (1997a).
References:
T. Dau, D. Püschel, and A. Kohlrausch.
A quantitative model of the effective signal processing in the
auditory system. I. Model structure.
The Journal of the Acoustical Society of America,
99(6):3615-3622, 1996a.
T. Dau, D. Püschel, and A. Kohlrausch.
A quantitative model of the effective signal processing in the
auditory system. II. Simulations and measurements.
The Journal of the Acoustical Society of America, 99:3623,
1996b.
T. Dau, B. Kollmeier, and A. Kohlrausch.
Modeling auditory processing of amplitude modulation. I. Detection
and masking with narrow-band carriers.
The Journal of the Acoustical Society of America, 102:2892,
1997a.
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