Cleaned up and revised the handling of resampling and bandsplitting in APM and

webrtc/modules/audio_processing/audio_processing_impl.h

Index: webrtc/modules/audio_processing/audio_processing_impl.h
diff --git a/webrtc/modules/audio_processing/audio_processing_impl.h b/webrtc/modules/audio_processing/audio_processing_impl.h
index 87e2224bbff89f981bc245986b2151c3bb747fd7..a31a6cc21498304a79eb3d89a27e80753fdf90da 100644
--- a/webrtc/modules/audio_processing/audio_processing_impl.h
+++ b/webrtc/modules/audio_processing/audio_processing_impl.h
@@ -127,6 +127,7 @@ class AudioProcessingImpl : public AudioProcessing {
       EXCLUSIVE_LOCKS_REQUIRED(crit_render_, crit_capture_);
 
  private:
+  class ApmSubmoduleStates;

[hlundin-webrtc, 2016/09/06 10:41:32]

I'm not fond of forward-declaring private subclasses. Make a proper declaration
here instead, and don't use an std::unique_ptr for the member variable below.

[peah-webrtc, 2016/09/07 06:28:11]

Done.

   struct ApmPublicSubmodules;
   struct ApmPrivateSubmodules;
 
@@ -160,21 +161,19 @@ class AudioProcessingImpl : public AudioProcessing {
   // that the capture thread blocks the render thread.
   // The struct is modified in a single-threaded manner by holding both the
   // render and capture locks.
-  int MaybeInitialize(const ProcessingConfig& config)
+  int MaybeInitialize(const ProcessingConfig& config, bool force_initialization)
       EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
 
   int MaybeInitializeRender(const ProcessingConfig& processing_config)
       EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
 
-  int MaybeInitializeCapture(const ProcessingConfig& processing_config)
+  int MaybeInitializeCapture(const ProcessingConfig& processing_config,
+                             bool force_initialization)
       EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
 
-  // Method for checking for the need of conversion. Accesses the formats
-  // structs in a read manner but the requirement for the render lock to be held
-  // was added as it currently anyway is always called in that manner.
-  bool rev_conversion_needed() const EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
-  bool render_check_rev_conversion_needed() const
-      EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
+  // Method for updating the state keeping track of the active submodules.
+  // Returns a bool indicating whether the state had changed.
+  bool UpdateActiveSubmoduleStates() EXCLUSIVE_LOCKS_REQUIRED(crit_capture_);
 
   // Methods requiring APM running in a single-threaded manner.
   // Are called with both the render and capture locks already
@@ -208,10 +207,6 @@ class AudioProcessingImpl : public AudioProcessing {
   // Capture-side exclusive methods possibly running APM in a multi-threaded
   // manner that are called with the render lock already acquired.
   int ProcessStreamLocked() EXCLUSIVE_LOCKS_REQUIRED(crit_capture_);
-  bool output_copy_needed() const EXCLUSIVE_LOCKS_REQUIRED(crit_capture_);
-  bool is_fwd_processed() const EXCLUSIVE_LOCKS_REQUIRED(crit_capture_);
-  bool fwd_synthesis_needed() const EXCLUSIVE_LOCKS_REQUIRED(crit_capture_);
-  bool fwd_analysis_needed() const EXCLUSIVE_LOCKS_REQUIRED(crit_capture_);
   void MaybeUpdateHistograms() EXCLUSIVE_LOCKS_REQUIRED(crit_capture_);
 
   // Render-side exclusive methods possibly running APM in a multi-threaded
@@ -221,9 +216,6 @@ class AudioProcessingImpl : public AudioProcessing {
                                  const StreamConfig& input_config,
                                  const StreamConfig& output_config)
       EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
-  bool is_rev_processed() const EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
-  bool rev_synthesis_needed() const EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
-  bool rev_analysis_needed() const EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
   int ProcessReverseStreamLocked() EXCLUSIVE_LOCKS_REQUIRED(crit_render_);
 
 // Debug dump methods that are internal and called without locks.
@@ -254,6 +246,9 @@ class AudioProcessingImpl : public AudioProcessing {
   rtc::CriticalSection crit_render_ ACQUIRED_BEFORE(crit_capture_);
   rtc::CriticalSection crit_capture_;
 
+  // Class containing information about what submodules are active.
+  std::unique_ptr<ApmSubmoduleStates> submodule_states_;

[hlundin-webrtc, 2016/09/06 10:41:32]

As said above, don't use std::unique_ptr. Let it be a plain member instead,
since you are not using any features of the unique_ptr anyway (it is populated
only once, in the ctor, and is never deleted before the dtor).

[peah-webrtc, 2016/09/07 06:28:11]

Sounds good!

Done.

+
   // Structs containing the pointers to the submodules.
   std::unique_ptr<ApmPublicSubmodules> public_submodules_;
   std::unique_ptr<ApmPrivateSubmodules> private_submodules_