tomwalters@12: // Copyright 2010, Thomas Walters
tomwalters@12: //
tomwalters@12: // AIM-C: A C++ implementation of the Auditory Image Model
tomwalters@12: // http://www.acousticscale.org/AIMC
tomwalters@12: //
tomwalters@12: // This program is free software: you can redistribute it and/or modify
tomwalters@12: // it under the terms of the GNU General Public License as published by
tomwalters@12: // the Free Software Foundation, either version 3 of the License, or
tomwalters@12: // (at your option) any later version.
tomwalters@12: //
tomwalters@12: // This program is distributed in the hope that it will be useful,
tomwalters@12: // but WITHOUT ANY WARRANTY; without even the implied warranty of
tomwalters@12: // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
tomwalters@12: // GNU General Public License for more details.
tomwalters@12: //
tomwalters@12: // You should have received a copy of the GNU General Public License
tomwalters@12: // along with this program.  If not, see <http://www.gnu.org/licenses/>.
tomwalters@12: 
tomwalters@12: /*!
tomwalters@12:  * \author Thomas Walters <tom@acousticscale.org>
tomwalters@12:  * \date created 2010/02/19
tomwalters@12:  * \version \$Id$
tomwalters@12:  */
tomwalters@12: 
tomwalters@15: #include <cmath>
tomwalters@15: 
tomwalters@12: #include "Modules/SSI/ModuleSSI.h"
tomwalters@12: 
tomwalters@12: namespace aimc {
tomwalters@12: ModuleSSI::ModuleSSI(Parameters *params) : Module(params) {
tomwalters@12:   module_description_ = "Size-shape image (aka the 'sscAI')";
tomwalters@12:   module_identifier_ = "ssi";
tomwalters@12:   module_type_ = "ssi";
tomwalters@12:   module_version_ = "$Id$";
tomwalters@12: 
tomwalters@17:   // do_pitch_cutoff_ = parameters_->DefaultBool("ssi.pitch_cutoff", false);
tomwalters@15:   ssi_width_cycles_ = parameters_->DefaultFloat("ssi.width_cycles", 20.0f);
tomwalters@12: }
tomwalters@12: 
tomwalters@12: ModuleSSI::~ModuleSSI() {
tomwalters@12: }
tomwalters@12: 
tomwalters@12: bool ModuleSSI::InitializeInternal(const SignalBank &input) {
tomwalters@12:   // Copy the parameters of the input signal bank into internal variables, so
tomwalters@12:   // that they can be checked later.
tomwalters@12:   sample_rate_ = input.sample_rate();
tomwalters@12:   buffer_length_ = input.buffer_length();
tomwalters@12:   channel_count_ = input.channel_count();
tomwalters@12: 
tomwalters@15:   float lowest_cf = input.centre_frequency(0);
tomwalters@15:   ssi_width_samples_ = sample_rate_ * ssi_width_cycles_ / lowest_cf;
tomwalters@15:   if (ssi_width_samples_ > buffer_length_) {
tomwalters@15:     ssi_width_samples_ = buffer_length_;
tomwalters@15:     float cycles = ssi_width_samples_ * lowest_cf / sample_rate_;
tomwalters@15:     LOG_INFO(_T("Requested SSI width of %f cycles is too long for the "
tomwalters@15:                 "input buffer length of %d samples. The SSI will be "
tomwalters@15:                 "truncated at %d samples wide. This corresponds to a width "
tomwalters@15:                 "of %f cycles."), ssi_width_cycles_, buffer_length_,
tomwalters@15:                 ssi_width_samples_, cycles);
tomwalters@15:     ssi_width_cycles_ = cycles;
tomwalters@15:   }
tomwalters@15:   output_.Initialize(channel_count_, ssi_width_samples_, sample_rate_);
tomwalters@12:   return true;
tomwalters@12: }
tomwalters@12: 
tomwalters@12: void ModuleSSI::ResetInternal() {
tomwalters@12: }
tomwalters@12: 
tomwalters@12: void ModuleSSI::Process(const SignalBank &input) {
tomwalters@12:   // Check to see if the module has been initialized. If not, processing
tomwalters@12:   // should not continue.
tomwalters@12:   if (!initialized_) {
tomwalters@13:     LOG_ERROR(_T("Module %s not initialized."), module_identifier_.c_str());
tomwalters@12:     return;
tomwalters@12:   }
tomwalters@12: 
tomwalters@12:   // Check that ths input this time is the same as the input passed to
tomwalters@12:   // Initialize()
tomwalters@12:   if (buffer_length_ != input.buffer_length()
tomwalters@12:       || channel_count_ != input.channel_count()) {
tomwalters@12:     LOG_ERROR(_T("Mismatch between input to Initialize() and input to "
tomwalters@13:                  "Process() in module %s."), module_identifier_.c_str());
tomwalters@12:     return;
tomwalters@12:   }
tomwalters@12: 
tomwalters@15:   output_.set_start_time(input.start_time());
tomwalters@12: 
tomwalters@15:   for (int ch = 0; ch < channel_count_; ++ch) {
tomwalters@15:     // Copy the buffer from input to output, addressing by h-value
tomwalters@15:     for (int i = 0; i < ssi_width_samples_; ++i) {
tomwalters@15:       float h = static_cast<float>(i) * ssi_width_cycles_
tomwalters@15:                 / static_cast<float>(ssi_width_samples_);
tomwalters@15:       float cycle_samples = sample_rate_ / input.centre_frequency(ch);
tomwalters@12: 
tomwalters@15:       // The index into the input array is a floating-point number, which is
tomwalters@15:       // split into a whole part and a fractional part. The whole part and
tomwalters@15:       // fractional part are found, and are used to linearly interpolate
tomwalters@15:       // between input samples to yield an output sample.
tomwalters@15:       double whole_part;
tomwalters@15:       float frac_part = modf(h * cycle_samples, &whole_part);
tomwalters@15:       int sample = static_cast<int>(whole_part);
tomwalters@15: 
tomwalters@15:       float val;
tomwalters@15:       if (sample < buffer_length_ - 1) {
tomwalters@15:         float curr_sample = input.sample(ch, sample);
tomwalters@15:         float next_sample = input.sample(ch, sample + 1);
tomwalters@15:         val = curr_sample + frac_part * (next_sample - curr_sample);
tomwalters@15:       } else {
tomwalters@15:         val = 0.0f;
tomwalters@15:       }
tomwalters@15:       output_.set_sample(ch, i, val);
tomwalters@15:     }
tomwalters@15:   }
tomwalters@12:   PushOutput();
tomwalters@12: }
tomwalters@12: }  // namespace aimc
tomwalters@12: