text: /*
   *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
   *
   *  Use of this source code is governed by a BSD-style license
   *  that can be found in the LICENSE file in the root of the source
   *  tree. An additional intellectual property rights grant can be found
   *  in the file PATENTS.  All contributing project authors may
   *  be found in the AUTHORS file in the root of the source tree.
   */
  
  #include "echo_cancellation_impl.h"
  
  #include <cassert>
  #include <string.h>
  
  #include "critical_section_wrapper.h"
  #include "echo_cancellation.h"
  
  #include "audio_processing_impl.h"
  #include "audio_buffer.h"
  
  namespace webrtc {
  
  typedef void Handle;
  
  namespace {
  WebRtc_Word16 MapSetting(EchoCancellation::SuppressionLevel level) {
    switch (level) {
      case EchoCancellation::kLowSuppression:
        return kAecNlpConservative;
      case EchoCancellation::kModerateSuppression:
        return kAecNlpModerate;
      case EchoCancellation::kHighSuppression:
        return kAecNlpAggressive;
    }
    assert(false);
    return -1;
  }
  
  AudioProcessing::Error MapError(int err) {
    switch (err) {
      case AEC_UNSUPPORTED_FUNCTION_ERROR:
        return AudioProcessing::kUnsupportedFunctionError;
      case AEC_BAD_PARAMETER_ERROR:
        return AudioProcessing::kBadParameterError;
      case AEC_BAD_PARAMETER_WARNING:
        return AudioProcessing::kBadStreamParameterWarning;
      default:
        // AEC_UNSPECIFIED_ERROR
        // AEC_UNINITIALIZED_ERROR
        // AEC_NULL_POINTER_ERROR
        return AudioProcessing::kUnspecifiedError;
    }
  }
  }  // namespace
  
  EchoCancellationImpl::EchoCancellationImpl(const AudioProcessingImpl* apm)
    : ProcessingComponent(apm),
      apm_(apm),
      drift_compensation_enabled_(false),
      metrics_enabled_(false),
      suppression_level_(kModerateSuppression),
      device_sample_rate_hz_(48000),
      stream_drift_samples_(0),
      was_stream_drift_set_(false),
      stream_has_echo_(false),
      delay_logging_enabled_(false) {}
  
  EchoCancellationImpl::~EchoCancellationImpl() {}
  
  int EchoCancellationImpl::ProcessRenderAudio(const AudioBuffer* audio) {
    if (!is_component_enabled()) {
      return apm_->kNoError;
    }
  
    assert(audio->samples_per_split_channel() <= 160);
    assert(audio->num_channels() == apm_->num_reverse_channels());
  
    int err = apm_->kNoError;
  
    // The ordering convention must be followed to pass to the correct AEC.
    size_t handle_index = 0;
    for (int i = 0; i < apm_->num_output_channels(); i++) {
      for (int j = 0; j < audio->num_channels(); j++) {
        Handle* my_handle = static_cast<Handle*>(handle(handle_index));
        err = WebRtcAec_BufferFarend(
            my_handle,
            audio->low_pass_split_data(j),
            static_cast<WebRtc_Word16>(audio->samples_per_split_channel()));
  
        if (err != apm_->kNoError) {
          return GetHandleError(my_handle);  // TODO(ajm): warning possible?
        }
  
        handle_index++;
      }
    }
  
    return apm_->kNoError;
  }
  
  int EchoCancellationImpl::ProcessCaptureAudio(AudioBuffer* audio) {
    if (!is_component_enabled()) {
      return apm_->kNoError;
    }
  
    if (!apm_->was_stream_delay_set()) {
      return apm_->kStreamParameterNotSetError;
    }
  
    if (drift_compensation_enabled_ && !was_stream_drift_set_) {
      return apm_->kStreamParameterNotSetError;
    }
  
    assert(audio->samples_per_split_channel() <= 160);
    assert(audio->num_channels() == apm_->num_output_channels());
  
    int err = apm_->kNoError;
  
    // The ordering convention must be followed to pass to the correct AEC.
    size_t handle_index = 0;
    stream_has_echo_ = false;
    for (int i = 0; i < audio->num_channels(); i++) {
      for (int j = 0; j < apm_->num_reverse_channels(); j++) {
        Handle* my_handle = handle(handle_index);
        err = WebRtcAec_Process(
            my_handle,
            audio->low_pass_split_data(i),
            audio->high_pass_split_data(i),
            audio->low_pass_split_data(i),
            audio->high_pass_split_data(i),
            static_cast<WebRtc_Word16>(audio->samples_per_split_channel()),
            apm_->stream_delay_ms(),
            stream_drift_samples_);
  
        if (err != apm_->kNoError) {
          err = GetHandleError(my_handle);
          // TODO(ajm): Figure out how to return warnings properly.
          if (err != apm_->kBadStreamParameterWarning) {
            return err;
          }
        }
  
        WebRtc_Word16 status = 0;
        err = WebRtcAec_get_echo_status(my_handle, &status);
        if (err != apm_->kNoError) {
          return GetHandleError(my_handle);
        }
  
        if (status == 1) {
          stream_has_echo_ = true;
        }
  
        handle_index++;
      }
    }
  
    was_stream_drift_set_ = false;
    return apm_->kNoError;
  }
  
  int EchoCancellationImpl::Enable(bool enable) {
    CriticalSectionScoped crit_scoped(apm_->crit());
    // Ensure AEC and AECM are not both enabled.
    if (enable && apm_->echo_control_mobile()->is_enabled()) {
      return apm_->kBadParameterError;
    }
  
    return EnableComponent(enable);
  }
  
  bool EchoCancellationImpl::is_enabled() const {
    return is_component_enabled();
  }
  
  int EchoCancellationImpl::set_suppression_level(SuppressionLevel level) {
    CriticalSectionScoped crit_scoped(apm_->crit());
    if (MapSetting(level) == -1) {
      return apm_->kBadParameterError;
    }
  
    suppression_level_ = level;
    return Configure();
  }
  
  EchoCancellation::SuppressionLevel EchoCancellationImpl::suppression_level()
      const {
    return suppression_level_;
  }
  
  int EchoCancellationImpl::enable_drift_compensation(bool enable) {
    CriticalSectionScoped crit_scoped(apm_->crit());
    drift_compensation_enabled_ = enable;
    return Configure();
  }
  
  bool EchoCancellationImpl::is_drift_compensation_enabled() const {
    return drift_compensation_enabled_;
  }
  
  int EchoCancellationImpl::set_device_sample_rate_hz(int rate) {
    CriticalSectionScoped crit_scoped(apm_->crit());
    if (rate < 8000 || rate > 96000) {
      return apm_->kBadParameterError;
    }
  
    device_sample_rate_hz_ = rate;
    return Initialize();
  }
  
  int EchoCancellationImpl::device_sample_rate_hz() const {
    return device_sample_rate_hz_;
  }
  
  int EchoCancellationImpl::set_stream_drift_samples(int drift) {
    was_stream_drift_set_ = true;
    stream_drift_samples_ = drift;
    return apm_->kNoError;
  }
  
  int EchoCancellationImpl::stream_drift_samples() const {
    return stream_drift_samples_;
  }
  
  int EchoCancellationImpl::enable_metrics(bool enable) {
    CriticalSectionScoped crit_scoped(apm_->crit());
    metrics_enabled_ = enable;
    return Configure();
  }
  
  bool EchoCancellationImpl::are_metrics_enabled() const {
    return metrics_enabled_;
  }
  
  // TODO(ajm): we currently just use the metrics from the first AEC. Think more
  //            aboue the best way to extend this to multi-channel.
  int EchoCancellationImpl::GetMetrics(Metrics* metrics) {
    CriticalSectionScoped crit_scoped(apm_->crit());
    if (metrics == NULL) {
      return apm_->kNullPointerError;
    }
  
    if (!is_component_enabled() || !metrics_enabled_) {
      return apm_->kNotEnabledError;
    }
  
    AecMetrics my_metrics;
    memset(&my_metrics, 0, sizeof(my_metrics));
    memset(metrics, 0, sizeof(Metrics));
  
    Handle* my_handle = static_cast<Handle*>(handle(0));
    int err = WebRtcAec_GetMetrics(my_handle, &my_metrics);
    if (err != apm_->kNoError) {
      return GetHandleError(my_handle);
    }
  
    metrics->residual_echo_return_loss.instant = my_metrics.rerl.instant;
    metrics->residual_echo_return_loss.average = my_metrics.rerl.average;
    metrics->residual_echo_return_loss.maximum = my_metrics.rerl.max;
    metrics->residual_echo_return_loss.minimum = my_metrics.rerl.min;
  
    metrics->echo_return_loss.instant = my_metrics.erl.instant;
    metrics->echo_return_loss.average = my_metrics.erl.average;
    metrics->echo_return_loss.maximum = my_metrics.erl.max;
    metrics->echo_return_loss.minimum = my_metrics.erl.min;
  
    metrics->echo_return_loss_enhancement.instant = my_metrics.erle.instant;
    metrics->echo_return_loss_enhancement.average = my_metrics.erle.average;
    metrics->echo_return_loss_enhancement.maximum = my_metrics.erle.max;
    metrics->echo_return_loss_enhancement.minimum = my_metrics.erle.min;
  
    metrics->a_nlp.instant = my_metrics.aNlp.instant;
    metrics->a_nlp.average = my_metrics.aNlp.average;
    metrics->a_nlp.maximum = my_metrics.aNlp.max;
    metrics->a_nlp.minimum = my_metrics.aNlp.min;
  
    return apm_->kNoError;
  }
  
  bool EchoCancellationImpl::stream_has_echo() const {
    return stream_has_echo_;
  }
  
  int EchoCancellationImpl::enable_delay_logging(bool enable) {
    CriticalSectionScoped crit_scoped(apm_->crit());
    delay_logging_enabled_ = enable;
    return Configure();
  }
  
  bool EchoCancellationImpl::is_delay_logging_enabled() const {
    return delay_logging_enabled_;
  }
  
  // TODO(bjornv): How should we handle the multi-channel case?
  int EchoCancellationImpl::GetDelayMetrics(int* median, int* std) {
    CriticalSectionScoped crit_scoped(apm_->crit());
    if (median == NULL) {
      return apm_->kNullPointerError;
    }
    if (std == NULL) {
      return apm_->kNullPointerError;
    }
  
    if (!is_component_enabled() || !delay_logging_enabled_) {
      return apm_->kNotEnabledError;
    }
  
    Handle* my_handle = static_cast<Handle*>(handle(0));
    if (WebRtcAec_GetDelayMetrics(my_handle, median, std) !=
        apm_->kNoError) {
      return GetHandleError(my_handle);
    }
  
    return apm_->kNoError;
  }
  
  int EchoCancellationImpl::Initialize() {
    int err = ProcessingComponent::Initialize();
    if (err != apm_->kNoError || !is_component_enabled()) {
      return err;
    }
  
    was_stream_drift_set_ = false;
  
    return apm_->kNoError;
  }
  
  void* EchoCancellationImpl::CreateHandle() const {
    Handle* handle = NULL;
    if (WebRtcAec_Create(&handle) != apm_->kNoError) {
      handle = NULL;
    } else {
      assert(handle != NULL);
    }
  
    return handle;
  }
  
  int EchoCancellationImpl::DestroyHandle(void* handle) const {
    assert(handle != NULL);
    return WebRtcAec_Free(static_cast<Handle*>(handle));
  }
  
  int EchoCancellationImpl::InitializeHandle(void* handle) const {
    assert(handle != NULL);
    return WebRtcAec_Init(static_cast<Handle*>(handle),
                         apm_->sample_rate_hz(),
                         device_sample_rate_hz_);
  }
  
  int EchoCancellationImpl::ConfigureHandle(void* handle) const {
    assert(handle != NULL);
    AecConfig config;
    config.metricsMode = metrics_enabled_;
    config.nlpMode = MapSetting(suppression_level_);
    config.skewMode = drift_compensation_enabled_;
    config.delay_logging = delay_logging_enabled_;
  
    return WebRtcAec_set_config(static_cast<Handle*>(handle), config);
  }
  
  int EchoCancellationImpl::num_handles_required() const {
    return apm_->num_output_channels() *
           apm_->num_reverse_channels();
  }
  
  int EchoCancellationImpl::GetHandleError(void* handle) const {
    assert(handle != NULL);
    return MapError(WebRtcAec_get_error_code(static_cast<Handle*>(handle)));
  }
  }  // namespace webrtc
  