view C++/Ear.C @ 610:01986636257a

Second check-in of Alex Brandmeyer's C++ implementation of CARFAC. Addressed style issues and completed implementation of remaining functions. Still needs proper testing of the output stages against the MATLAB version, and runtime functions need improvements in efficiency.

// Copyright 2013 Matt R. Flax <flatmax\@> All Rights Reserved.
// Author Matt Flax <flatmax@>
//
// This C++ file is part of an implementation of Lyon's cochlear model:
// "Cascade of Asymmetric Resonators with Fast-Acting Compression"
// to supplement Lyon's upcoming book "Human and Machine Hearing"
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/**
    \author {Matt Flax <flatmax\@>}
    \date 2013.02.08
*/

#include "Ear.H"

Ear::Ear(FP_TYPE fs_) {
    fs=fs_; // set the specified sample rate
    design();
}

Ear::Ear(void) {
    fs=DEFAULT_SAMPLERATE; // Use the default sample rate
    design();
}

Ear::~Ear(void) {
}

void Ear::design(void) {

    // first figure out how many filter stages (PZFC/car.AC channels):
    FP_TYPE pole_Hz = car.param.first_pole_theta * fs / (2.*M_PI);
    n_ch = 0;
    while (pole_Hz > car.param.min_pole_Hz) {
        n_ch = n_ch + 1;
        pole_Hz = pole_Hz - car.param.ERB_per_step *
                  PsychoAcoustics::Hz2ERB(pole_Hz, car.param.ERB_break_freq, car.param.ERB_Q);
    }
    // Now we have n_ch, the number of channels, so can make the array
    // and compute all the frequencies again to put into it:
    car.pole_freqs.resize(n_ch, NoChange);
    pole_Hz = car.param.first_pole_theta * fs / (2.*M_PI);
    for (int ch = 0; ch<n_ch; ch++) {
        car.pole_freqs[ch] = pole_Hz;
        pole_Hz = pole_Hz - car.param.ERB_per_step *
                  PsychoAcoustics::Hz2ERB(pole_Hz, car.param.ERB_break_freq, car.param.ERB_Q);
    }
    // now we have n_ch, the number of channels, and pole_freqs array

    max_channels_per_octave = (FP_TYPE)(log(2.) / log(car.pole_freqs[0]/car.pole_freqs[1]));

    // convert to include an ear_array, each w coeffs and state...
    car.designFilters(fs, n_ch);
    AGC.designAGC(fs, n_ch);
    //IHC.designIHC(CF_IHC_params, fs, n_ch);
}