Implement runtime audio post-processing pipeline. See go/cast_audio.json

chromecast/media/cma/backend/alsa/filter_group.h

Index: chromecast/media/cma/backend/alsa/filter_group.h
diff --git a/chromecast/media/cma/backend/alsa/filter_group.h b/chromecast/media/cma/backend/alsa/filter_group.h
index 7db908c10aad6f643d28a19a729537ef81220a03..11e97cf16c687215455d1ae6fcab42287cc839de 100644
--- a/chromecast/media/cma/backend/alsa/filter_group.h
+++ b/chromecast/media/cma/backend/alsa/filter_group.h
@@ -13,7 +13,7 @@
 #include <vector>
 
 #include "base/macros.h"
-#include "chromecast/media/cma/backend/alsa/audio_filter_factory.h"
+#include "base/values.h"
 #include "chromecast/media/cma/backend/alsa/stream_mixer_alsa.h"
 #include "chromecast/public/volume_control.h"
 
@@ -24,6 +24,8 @@ class AudioBus;
 namespace chromecast {
 namespace media {
 
+class PostProcessingPipeline;
+
 // FilterGroup contains state for an AudioFilter.
 // It takes multiple StreamMixerAlsa::InputQueues,
 // mixes them, and processes them.
@@ -37,16 +39,17 @@ class FilterGroup {
   // entry in |input_types| to be processed by this group.
   // |filter_type| is passed to AudioFilterFactory to create an AudioFilter.
   FilterGroup(const std::unordered_set<std::string>& input_types,
-              AudioFilterFactory::FilterType filter_type,
-              AudioContentType content_type);
+              AudioContentType content_type,
+              int channels,
+              const base::ListValue* filter_list);
   ~FilterGroup();
 
   AudioContentType content_type() const { return content_type_; }
 
   void set_volume(float volume) { volume_ = volume; }
 
-  // Sets the sample rate and format in the AudioFilter.
-  void Initialize(int output_samples_per_second, ::media::SampleFormat format);
+  // Sets the sample rate of the post-processors.
+  void Initialize(int output_samples_per_second);
 
   // Returns |true| if this FilterGroup is appropriate to process |input|.
   bool CanProcessInput(StreamMixerAlsa::InputQueue* input);
@@ -74,10 +77,11 @@ class FilterGroup {
 
   const std::unordered_set<std::string> input_types_;
   const AudioContentType content_type_;
+  const int channels_;
+  int silence_frames_to_filter_ = 0;
   std::vector<StreamMixerAlsa::InputQueue*> active_inputs_;
 
   int output_samples_per_second_;
-  ::media::SampleFormat sample_format_;
 
   float volume_ = 0.0f;
 
@@ -88,7 +92,7 @@ class FilterGroup {
   std::unique_ptr<::media::AudioBus> mixed_;
   std::vector<uint8_t> interleaved_;
 
-  std::unique_ptr<AudioFilterInterface> audio_filter_;
+  std::unique_ptr<PostProcessingPipeline> post_processing_pipeline_;
   int silence_frames_filtered_;
 
   DISALLOW_COPY_AND_ASSIGN(FilterGroup);
@@ -96,4 +100,5 @@ class FilterGroup {
 
 }  // namespace media
 }  // namespace chromecast
+
 #endif  // CHROMECAST_MEDIA_CMA_BACKEND_ALSA_FILTER_GROUP_H_