1 files changed, 0 insertions, 393 deletions
diff --git a/dom/media/webspeech/recognition/energy_endpointer.cc b/dom/media/webspeech/recognition/energy_endpointer.cc
deleted file mode 100644
index 9b1a81589..000000000
--- a/dom/media/webspeech/recognition/energy_endpointer.cc
+++ /dev/null
@@ -1,393 +0,0 @@
-// Copyright (c) 2013 The Chromium Authors. All rights reserved.
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//    * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//    * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//    * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#include "energy_endpointer.h"
-
-#include <math.h>
-
-namespace {
-
-// Returns the RMS (quadratic mean) of the input signal.
-float RMS(const int16_t* samples, int num_samples) {
-  int64_t ssq_int64_t = 0;
-  int64_t sum_int64_t = 0;
-  for (int i = 0; i < num_samples; ++i) {
-    sum_int64_t += samples[i];
-    ssq_int64_t += samples[i] * samples[i];
-  }
-  // now convert to floats.
-  double sum = static_cast<double>(sum_int64_t);
-  sum /= num_samples;
-  double ssq = static_cast<double>(ssq_int64_t);
-  return static_cast<float>(sqrt((ssq / num_samples) - (sum * sum)));
-}
-
-int64_t Secs2Usecs(float seconds) {
-  return static_cast<int64_t>(0.5 + (1.0e6 * seconds));
-}
-
-float GetDecibel(float value) {
-  if (value > 1.0e-100)
-    return 20 * log10(value);
-  return -2000.0;
-}
-
-}  // namespace
-
-namespace mozilla {
-
-// Stores threshold-crossing histories for making decisions about the speech
-// state.
-class EnergyEndpointer::HistoryRing {
- public:
-  HistoryRing() : insertion_index_(0) {}
-
-  // Resets the ring to |size| elements each with state |initial_state|
-  void SetRing(int size, bool initial_state);
-
-  // Inserts a new entry into the ring and drops the oldest entry.
-  void Insert(int64_t time_us, bool decision);
-
-  // Returns the time in microseconds of the most recently added entry.
-  int64_t EndTime() const;
-
-  // Returns the sum of all intervals during which 'decision' is true within
-  // the time in seconds specified by 'duration'. The returned interval is
-  // in seconds.
-  float RingSum(float duration_sec);
-
- private:
-  struct DecisionPoint {
-    int64_t time_us;
-    bool decision;
-  };
-
-  std::vector<DecisionPoint> decision_points_;
-  int insertion_index_;  // Index at which the next item gets added/inserted.
-
-  HistoryRing(const HistoryRing&);
-  void operator=(const HistoryRing&);
-};
-
-void EnergyEndpointer::HistoryRing::SetRing(int size, bool initial_state) {
-  insertion_index_ = 0;
-  decision_points_.clear();
-  DecisionPoint init = { -1, initial_state };
-  decision_points_.resize(size, init);
-}
-
-void EnergyEndpointer::HistoryRing::Insert(int64_t time_us, bool decision) {
-  decision_points_[insertion_index_].time_us = time_us;
-  decision_points_[insertion_index_].decision = decision;
-  insertion_index_ = (insertion_index_ + 1) % decision_points_.size();
-}
-
-int64_t EnergyEndpointer::HistoryRing::EndTime() const {
-  int ind = insertion_index_ - 1;
-  if (ind < 0)
-    ind = decision_points_.size() - 1;
-  return decision_points_[ind].time_us;
-}
-
-float EnergyEndpointer::HistoryRing::RingSum(float duration_sec) {
-  if (!decision_points_.size())
-    return 0.0;
-
-  int64_t sum_us = 0;
-  int ind = insertion_index_ - 1;
-  if (ind < 0)
-    ind = decision_points_.size() - 1;
-  int64_t end_us = decision_points_[ind].time_us;
-  bool is_on = decision_points_[ind].decision;
-  int64_t start_us = end_us - static_cast<int64_t>(0.5 + (1.0e6 * duration_sec));
-  if (start_us < 0)
-    start_us = 0;
-  size_t n_summed = 1;  // n points ==> (n-1) intervals
-  while ((decision_points_[ind].time_us > start_us) &&
-         (n_summed < decision_points_.size())) {
-    --ind;
-    if (ind < 0)
-      ind = decision_points_.size() - 1;
-    if (is_on)
-      sum_us += end_us - decision_points_[ind].time_us;
-    is_on = decision_points_[ind].decision;
-    end_us = decision_points_[ind].time_us;
-    n_summed++;
-  }
-
-  return 1.0e-6f * sum_us;  //  Returns total time that was super threshold.
-}
-
-EnergyEndpointer::EnergyEndpointer()
-    : status_(EP_PRE_SPEECH),
-      offset_confirm_dur_sec_(0),
-      endpointer_time_us_(0),
-      fast_update_frames_(0),
-      frame_counter_(0),
-      max_window_dur_(4.0),
-      sample_rate_(0),
-      history_(new HistoryRing()),
-      decision_threshold_(0),
-      estimating_environment_(false),
-      noise_level_(0),
-      rms_adapt_(0),
-      start_lag_(0),
-      end_lag_(0),
-      user_input_start_time_us_(0) {
-}
-
-EnergyEndpointer::~EnergyEndpointer() {
-}
-
-int EnergyEndpointer::TimeToFrame(float time) const {
-  return static_cast<int32_t>(0.5 + (time / params_.frame_period()));
-}
-
-void EnergyEndpointer::Restart(bool reset_threshold) {
-  status_ = EP_PRE_SPEECH;
-  user_input_start_time_us_ = 0;
-
-  if (reset_threshold) {
-    decision_threshold_ = params_.decision_threshold();
-    rms_adapt_ = decision_threshold_;
-    noise_level_ = params_.decision_threshold() / 2.0f;
-    frame_counter_ = 0;  // Used for rapid initial update of levels.
-  }
-
-  // Set up the memories to hold the history windows.
-  history_->SetRing(TimeToFrame(max_window_dur_), false);
-
-  // Flag that indicates that current input should be used for
-  // estimating the environment. The user has not yet started input
-  // by e.g. pressed the push-to-talk button. By default, this is
-  // false for backward compatibility.
-  estimating_environment_ = false;
-}
-
-void EnergyEndpointer::Init(const EnergyEndpointerParams& params) {
-  params_ = params;
-
-  // Find the longest history interval to be used, and make the ring
-  // large enough to accommodate that number of frames.  NOTE: This
-  // depends upon ep_frame_period being set correctly in the factory
-  // that did this instantiation.
-  max_window_dur_ = params_.onset_window();
-  if (params_.speech_on_window() > max_window_dur_)
-    max_window_dur_ = params_.speech_on_window();
-  if (params_.offset_window() > max_window_dur_)
-    max_window_dur_ = params_.offset_window();
-  Restart(true);
-
-  offset_confirm_dur_sec_ = params_.offset_window() -
-                            params_.offset_confirm_dur();
-  if (offset_confirm_dur_sec_ < 0.0)
-    offset_confirm_dur_sec_ = 0.0;
-
-  user_input_start_time_us_ = 0;
-
-  // Flag that indicates that  current input should be used for
-  // estimating the environment. The user has not yet started input
-  // by e.g. pressed the push-to-talk button. By default, this is
-  // false for backward compatibility.
-  estimating_environment_ = false;
-  // The initial value of the noise and speech levels is inconsequential.
-  // The level of the first frame will overwrite these values.
-  noise_level_ = params_.decision_threshold() / 2.0f;
-  fast_update_frames_ =
-      static_cast<int64_t>(params_.fast_update_dur() / params_.frame_period());
-
-  frame_counter_ = 0;  // Used for rapid initial update of levels.
-
-  sample_rate_ = params_.sample_rate();
-  start_lag_ = static_cast<int>(sample_rate_ /
-                                params_.max_fundamental_frequency());
-  end_lag_ = static_cast<int>(sample_rate_ /
-                              params_.min_fundamental_frequency());
-}
-
-void EnergyEndpointer::StartSession() {
-  Restart(true);
-}
-
-void EnergyEndpointer::EndSession() {
-  status_ = EP_POST_SPEECH;
-}
-
-void EnergyEndpointer::SetEnvironmentEstimationMode() {
-  Restart(true);
-  estimating_environment_ = true;
-}
-
-void EnergyEndpointer::SetUserInputMode() {
-  estimating_environment_ = false;
-  user_input_start_time_us_ = endpointer_time_us_;
-}
-
-void EnergyEndpointer::ProcessAudioFrame(int64_t time_us,
-                                         const int16_t* samples,
-                                         int num_samples,
-                                         float* rms_out) {
-  endpointer_time_us_ = time_us;
-  float rms = RMS(samples, num_samples);
-
-  // Check that this is user input audio vs. pre-input adaptation audio.
-  // Input audio starts when the user indicates start of input, by e.g.
-  // pressing push-to-talk. Audio recieved prior to that is used to update
-  // noise and speech level estimates.
-  if (!estimating_environment_) {
-    bool decision = false;
-    if ((endpointer_time_us_ - user_input_start_time_us_) <
-        Secs2Usecs(params_.contamination_rejection_period())) {
-      decision = false;
-      //PR_LOG(GetSpeechRecognitionLog(), PR_LOG_DEBUG, ("decision: forced to false, time: %d", endpointer_time_us_));
-    } else {
-      decision = (rms > decision_threshold_);
-    }
-
-    history_->Insert(endpointer_time_us_, decision);
-
-    switch (status_) {
-      case EP_PRE_SPEECH:
-        if (history_->RingSum(params_.onset_window()) >
-            params_.onset_detect_dur()) {
-          status_ = EP_POSSIBLE_ONSET;
-        }
-        break;
-
-      case EP_POSSIBLE_ONSET: {
-        float tsum = history_->RingSum(params_.onset_window());
-        if (tsum > params_.onset_confirm_dur()) {
-          status_ = EP_SPEECH_PRESENT;
-        } else {  // If signal is not maintained, drop back to pre-speech.
-          if (tsum <= params_.onset_detect_dur())
-            status_ = EP_PRE_SPEECH;
-        }
-        break;
-      }
-
-      case EP_SPEECH_PRESENT: {
-        // To induce hysteresis in the state residency, we allow a
-        // smaller residency time in the on_ring, than was required to
-        // enter the SPEECH_PERSENT state.
-        float on_time = history_->RingSum(params_.speech_on_window());
-        if (on_time < params_.on_maintain_dur())
-          status_ = EP_POSSIBLE_OFFSET;
-        break;
-      }
-
-      case EP_POSSIBLE_OFFSET:
-        if (history_->RingSum(params_.offset_window()) <=
-            offset_confirm_dur_sec_) {
-          // Note that this offset time may be beyond the end
-          // of the input buffer in a real-time system.  It will be up
-          // to the RecognizerSession to decide what to do.
-          status_ = EP_PRE_SPEECH;  // Automatically reset for next utterance.
-        } else {  // If speech picks up again we allow return to SPEECH_PRESENT.
-          if (history_->RingSum(params_.speech_on_window()) >=
-              params_.on_maintain_dur())
-            status_ = EP_SPEECH_PRESENT;
-        }
-        break;
-
-      default:
-        break;
-    }
-
-    // If this is a quiet, non-speech region, slowly adapt the detection
-    // threshold to be about 6dB above the average RMS.
-    if ((!decision) && (status_ == EP_PRE_SPEECH)) {
-      decision_threshold_ = (0.98f * decision_threshold_) + (0.02f * 2 * rms);
-      rms_adapt_ = decision_threshold_;
-    } else {
-      // If this is in a speech region, adapt the decision threshold to
-      // be about 10dB below the average RMS. If the noise level is high,
-      // the threshold is pushed up.
-      // Adaptation up to a higher level is 5 times faster than decay to
-      // a lower level.
-      if ((status_ == EP_SPEECH_PRESENT) && decision) {
-        if (rms_adapt_ > rms) {
-          rms_adapt_ = (0.99f * rms_adapt_) + (0.01f * rms);
-        } else {
-          rms_adapt_ = (0.95f * rms_adapt_) + (0.05f * rms);
-        }
-        float target_threshold = 0.3f * rms_adapt_ +  noise_level_;
-        decision_threshold_ = (.90f * decision_threshold_) +
-                              (0.10f * target_threshold);
-      }
-    }
-
-    // Set a floor
-    if (decision_threshold_ < params_.min_decision_threshold())
-      decision_threshold_ = params_.min_decision_threshold();
-  }
-
-  // Update speech and noise levels.
-  UpdateLevels(rms);
-  ++frame_counter_;
-
-  if (rms_out)
-    *rms_out = GetDecibel(rms);
-}
-
-float EnergyEndpointer::GetNoiseLevelDb() const {
-  return GetDecibel(noise_level_);
-}
-
-void EnergyEndpointer::UpdateLevels(float rms) {
-  // Update quickly initially. We assume this is noise and that
-  // speech is 6dB above the noise.
-  if (frame_counter_ < fast_update_frames_) {
-    // Alpha increases from 0 to (k-1)/k where k is the number of time
-    // steps in the initial adaptation period.
-    float alpha = static_cast<float>(frame_counter_) /
-        static_cast<float>(fast_update_frames_);
-    noise_level_ = (alpha * noise_level_) + ((1 - alpha) * rms);
-    //PR_LOG(GetSpeechRecognitionLog(), PR_LOG_DEBUG, ("FAST UPDATE, frame_counter_ %d, fast_update_frames_ %d", frame_counter_, fast_update_frames_));
-  } else {
-    // Update Noise level. The noise level adapts quickly downward, but
-    // slowly upward. The noise_level_ parameter is not currently used
-    // for threshold adaptation. It is used for UI feedback.
-    if (noise_level_ < rms)
-      noise_level_ = (0.999f * noise_level_) + (0.001f * rms);
-    else
-      noise_level_ = (0.95f * noise_level_) + (0.05f * rms);
-  }
-  if (estimating_environment_ || (frame_counter_ < fast_update_frames_)) {
-    decision_threshold_ = noise_level_ * 2; // 6dB above noise level.
-    // Set a floor
-    if (decision_threshold_ < params_.min_decision_threshold())
-      decision_threshold_ = params_.min_decision_threshold();
-  }
-}
-
-EpStatus EnergyEndpointer::Status(int64_t* status_time)  const {
-  *status_time = history_->EndTime();
-  return status_;
-}
-
-}  // namespace mozilla