blob: 84cfc350ce210503653f63704280ad53f9087a3a [file] [log] [blame]
// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <cstdint>
#include <memory>
#include <string>
#include <vector>
#include "base/containers/flat_map.h"
#include "base/macros.h"
#include "chromecast/public/media/audio_post_processor_shlib.h"
#include "chromecast/public/media/media_pipeline_backend.h"
namespace base {
class Value;
} // namespace base
namespace chromecast {
namespace media {
class FilterGroup;
class PostProcessingPipelineParser;
class PostProcessingPipelineFactory;
// Provides mixer and post-processing functionality for StreamMixer.
// Internally, MixerPipeline is a tree of post processors with two taps -
// LoopbackOutput and Output. Calling MixAndFilter causes the pipeline to pull
// data from inputs, mixing and filtering as described in cast_audio.json.
class MixerPipeline {
// Attempts to create a pipeline from |config|.
// Returns nullptr if config fails to parse.
static std::unique_ptr<MixerPipeline> CreateMixerPipeline(
PostProcessingPipelineParser* parser,
PostProcessingPipelineFactory* factory,
int expected_input_channels);
// Sets the sample rate of all processors.
void Initialize(int samples_per_second, int frames_per_write);
// Returns the FilterGroup that should process a stream with |device_id| or
// |nullptr| if no matching FilterGroup is found.
FilterGroup* GetInputGroup(const std::string& device_id);
// Polls |MixerInput|s for |frames_per_write| frames of audio data, mixes the
// inputs, and applies PostProcessors.
// |rendering_delay| is the rendering delay of the output device, and is used
// to calculate the delay from various points in the pipeline.
void MixAndFilter(
int frames_per_write,
MediaPipelineBackend::AudioDecoder::RenderingDelay rendering_delay);
// Returns the output data from the "mix" group.
float* GetLoopbackOutput();
// Returns the output data from the "linearize" group.
float* GetOutput();
// Returns the number of channels that will be present in GetLoopbackOutput().
int GetLoopbackChannelCount() const;
// Returns the number of channels that will be present in GetOutput().
int GetOutputChannelCount() const;
// Attempts to send |config| to PostProcessors with |name|.
void SetPostProcessorConfig(const std::string& name,
const std::string& config);
// Returns the rendering delay between audio coming from GetLoopbackOutput()
// and GetOutput(), i.e. the group delay of PostProcessors in "linearize"
int64_t GetPostLoopbackRenderingDelayMicroseconds() const;
// Informs FilterGroups and PostProcessors which channel will be played out.
// |playout_channel| may be |-1| to signal all channels will be played out.
void SetPlayoutChannel(int playout_channel);
// Determines whether the pipeline is still ringing out after all input
// streams have stopped playing.
bool IsRinging() const;
// External classes should call CreateMixerPipeline.
// Attempts to build a pipeline using |config|. Returns |true| IFF successful.
bool BuildPipeline(PostProcessingPipelineParser* config,
PostProcessingPipelineFactory* factory,
int expected_input_channels);
// Adds |ids| to the list of DeviceIds |filter_group| can process.
bool SetGroupDeviceIds(const base::Value* ids, FilterGroup* filter_group);
std::vector<std::unique_ptr<FilterGroup>> filter_groups_;
base::flat_map<std::string, FilterGroup*> stream_sinks_;
FilterGroup* loopback_output_group_ = nullptr;
FilterGroup* output_group_ = nullptr;
} // namespace media
} // namespace chromecast