view trunk/src/Modules/Strobes/ModuleLocalMax.cc @ 690:76f749d29b48

Fix memory leak in CARFAC.

Also get rid of most uses of auto, which tend to hurt readability
unless the type name is particularly long, especially when it masks
pointers.

// Copyright 2010, Thomas Walters
//
// AIM-C: A C++ implementation of the Auditory Image Model
// http://www.acousticscale.org/AIMC
//
// 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.

/*!
 * \file
 * \brief 
 *
 * \author Thomas Walters <[e-mail]>
 * \date created 2010/02/23
 * \version \$Id$
 */

#include <math.h>
#include "Modules/Strobes/ModuleLocalMax.h"

namespace aimc {
ModuleLocalMax::ModuleLocalMax(Parameters *params) : Module(params) {
  module_description_ = "Local maximum strobe criterion: decaying threshold "
                        "with timeout";
  module_identifier_ = "local_max";
  module_type_ = "strobes";
  module_version_ = "$Id: $";

  decay_time_ms_ = parameters_->DefaultFloat("strobes.decay_time_ms", 20.0f);
  timeout_ms_ = parameters_->DefaultFloat("strobes.timeout_ms", 3.0f);
}

ModuleLocalMax::~ModuleLocalMax() {
}

bool ModuleLocalMax::InitializeInternal(const SignalBank &input) {
  // Copy the parameters of the input signal bank into internal variables, so
  // that they can be checked later.
  sample_rate_ = input.sample_rate();
  buffer_length_ = input.buffer_length();
  channel_count_ = input.channel_count();
  output_.Initialize(input);
  strobe_timeout_samples_ = floor(timeout_ms_ * sample_rate_ / 1000.0f);
  strobe_decay_samples_ = floor(decay_time_ms_ * sample_rate_ / 1000.0f);
  ResetInternal();
  return true;
}

void ModuleLocalMax::ResetInternal() {
  threshold_.clear();
  threshold_.resize(channel_count_, 0.0f);

  decay_constant_.clear();
  decay_constant_.resize(channel_count_, 1.0f);

  prev_sample_.clear();
  prev_sample_.resize(channel_count_, 10000.0f);
  curr_sample_.clear();
  curr_sample_.resize(channel_count_, 5000.0f);
  next_sample_.clear();
  next_sample_.resize(channel_count_, 0.0f);
}

void ModuleLocalMax::Process(const SignalBank &input) {
  // Check to see if the module has been initialized. If not, processing
  // should not continue.
  if (!initialized_) {
    LOG_ERROR(_T("Module %s not initialized."), module_identifier_.c_str());
    return;
  }

  // Check that ths input this time is the same as the input passed to
  // Initialize()
  if (buffer_length_ != input.buffer_length()
      || channel_count_ != input.channel_count()) {
    LOG_ERROR(_T("Mismatch between input to Initialize() and input to "
                 "Process() in module %s."), module_identifier_.c_str());
    return;
  }

  for (int ch = 0; ch < output_.channel_count(); ch++) {
    output_.ResetStrobes(ch);
  }
  output_.set_start_time(input.start_time());
  for (int i = 0; i < input.buffer_length(); i++) {
    for (int ch = 0; ch < input.channel_count(); ++ch) {
      // curr_sample is the sample at time (i - 1)
      prev_sample_[ch] = curr_sample_[ch];
      curr_sample_[ch] = next_sample_[ch];
      next_sample_[ch] = input.sample(ch, i);
      // Copy input signal to output signal
      output_.set_sample(ch, i, input.sample(ch, i));

      // If the current sample is above threshold, the threshold is raised to
      // the level of the current sample, and decays from there.
      if (curr_sample_[ch] >= threshold_[ch]) {
        threshold_[ch] = curr_sample_[ch];
        decay_constant_[ch] = threshold_[ch] / strobe_decay_samples_;

        // If the current sample is also a peak, then it is a potential strobe
        // point.
        if (prev_sample_[ch] < curr_sample_[ch]
            && next_sample_[ch] < curr_sample_[ch]) {
          // If there are no strobes so far in this channel, then the sample
          // is definitely a strobe (this means that the timeout is not 
          // respected across frame boundaries. This is a minor bug, but I
          // don't believe that it's serious enough to warrant updating the
          // samples since last strobe all the time.)
          int count = output_.strobe_count(ch);
          if (count > 0) {
            // If there are previous strobes, then calculate the time since
            // the last one. If it's long enough, then this is a strobe point,
            // if not, then just move on.
            int samples_since_last = (i - 1) - output_.strobe(ch, count - 1);
            if (samples_since_last > strobe_timeout_samples_) {
              output_.AddStrobe(ch, i - 1);
            }
          } else {
            output_.AddStrobe(ch, i - 1);
          }
        }
      }

      // Update the threshold, decaying as necessary
      if (threshold_[ch] > decay_constant_[ch])
        threshold_[ch] -= decay_constant_[ch];
      else
        threshold_[ch] = 0.0f;
    }
  }
  PushOutput();
}
}  // namespace aimc