Fix the stereo support in IntelligibilityEnhancer

webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.h

 /*
  *  Copyright (c) 2014 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.
  */
 
 #ifndef WEBRTC_MODULES_AUDIO_PROCESSING_INTELLIGIBILITY_INTELLIGIBILITY_ENHANCER_H_
 #define WEBRTC_MODULES_AUDIO_PROCESSING_INTELLIGIBILITY_INTELLIGIBILITY_ENHANCER_H_
 
 #include <complex>
 #include <memory>
 #include <vector>
 
 #include "webrtc/common_audio/lapped_transform.h"
 #include "webrtc/common_audio/channel_buffer.h"
 #include "webrtc/modules/audio_processing/intelligibility/intelligibility_utils.h"
 #include "webrtc/modules/audio_processing/vad/voice_activity_detector.h"
 
 namespace webrtc {
 
 // Speech intelligibility enhancement module. Reads render and capture
 // audio streams and modifies the render stream with a set of gains per
 // frequency bin to enhance speech against the noise background.
 // Details of the model and algorithm can be found in the original paper:
 // http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6882788
-class IntelligibilityEnhancer {
+class IntelligibilityEnhancer : public LappedTransform::Callback {
  public:
   IntelligibilityEnhancer(int sample_rate_hz, size_t num_render_channels);
 
   // Sets the capture noise magnitude spectrum estimate.
   void SetCaptureNoiseEstimate(std::vector<float> noise);
 
   // Reads chunk of speech in time domain and updates with modified signal.
   void ProcessRenderAudio(float* const* audio,
                           int sample_rate_hz,
                           size_t num_channels);
   bool active() const;
 
+ protected:
+  // All in frequency domain, receives input |in_block|, applies
+  // intelligibility enhancement, and writes result to |out_block|.
+  void ProcessAudioBlock(const std::complex<float>* const* in_block,
+                         size_t in_channels,
+                         size_t frames,
+                         size_t out_channels,
+                         std::complex<float>* const* out_block) override;
+
  private:
-  // Provides access point to the frequency domain.
-  class TransformCallback : public LappedTransform::Callback {
-   public:
-    TransformCallback(IntelligibilityEnhancer* parent);
-
-    // All in frequency domain, receives input |in_block|, applies
-    // intelligibility enhancement, and writes result to |out_block|.
-    void ProcessAudioBlock(const std::complex<float>* const* in_block,
-                           size_t in_channels,
-                           size_t frames,
-                           size_t out_channels,
-                           std::complex<float>* const* out_block) override;
-
-   private:
-    IntelligibilityEnhancer* parent_;
-  };
-  friend class TransformCallback;
   FRIEND_TEST_ALL_PREFIXES(IntelligibilityEnhancerTest, TestErbCreation);
   FRIEND_TEST_ALL_PREFIXES(IntelligibilityEnhancerTest, TestSolveForGains);
 
-  // Updates power computation and analysis with |in_block_|,
-  // and writes modified speech to |out_block|.
-  void ProcessClearBlock(const std::complex<float>* in_block,
-                         std::complex<float>* out_block);
-
   // Bisection search for optimal |lambda|.
   void SolveForLambda(float power_target);
 
   // Transforms freq gains to ERB gains.
   void UpdateErbGains();
 
   // Returns number of ERB filters.
   static size_t GetBankSize(int sample_rate, size_t erb_resolution);
 
   // Initializes ERB filterbank.
   std::vector<std::vector<float>> CreateErbBank(size_t num_freqs);
 
   // Analytically solves quadratic for optimal gains given |lambda|.
   // Negative gains are set to 0. Stores the results in |sols|.
   void SolveForGainsGivenLambda(float lambda, size_t start_freq, float* sols);
 
   // Returns true if the audio is speech.
   bool IsSpeech(const float* audio);
 
   const size_t freqs_;         // Num frequencies in frequency domain.
   const size_t chunk_length_;  // Chunk size in samples.
   const size_t bank_size_;     // Num ERB filters.
   const int sample_rate_hz_;
   const size_t num_render_channels_;
 
   intelligibility::PowerEstimator<std::complex<float>> clear_power_estimator_;
   std::unique_ptr<intelligibility::PowerEstimator<float>>
       noise_power_estimator_;
-  std::unique_ptr<float[]> filtered_clear_pow_;
-  std::unique_ptr<float[]> filtered_noise_pow_;
-  std::unique_ptr<float[]> center_freqs_;
+  std::vector<float> filtered_clear_pow_;
+  std::vector<float> filtered_noise_pow_;
+  std::vector<float> center_freqs_;
   std::vector<std::vector<float>> capture_filter_bank_;
   std::vector<std::vector<float>> render_filter_bank_;
   size_t start_freq_;
 
-  std::unique_ptr<float[]> gains_eq_;  // Pre-filter modified gains.
+  std::vector<float> gains_eq_;  // Pre-filter modified gains.
   intelligibility::GainApplier gain_applier_;
 
-  // Destination buffers used to reassemble blocked chunks before overwriting
-  // the original input array with modifications.
-  ChannelBuffer<float> temp_render_out_buffer_;
-
-  TransformCallback render_callback_;
   std::unique_ptr<LappedTransform> render_mangler_;
 
   VoiceActivityDetector vad_;
   std::vector<int16_t> audio_s16_;
   size_t chunks_since_voice_;
   bool is_speech_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_INTELLIGIBILITY_INTELLIGIBILITY_ENHANCER_H_