| // Copyright 2015 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 "chromecast/media/cma/backend/alsa/audio_decoder_alsa.h" |
| |
| #include <time.h> |
| |
| #include <algorithm> |
| #include <limits> |
| |
| #include "base/callback_helpers.h" |
| #include "base/logging.h" |
| #include "base/macros.h" |
| #include "base/trace_event/trace_event.h" |
| #include "chromecast/base/task_runner_impl.h" |
| #include "chromecast/media/cma/backend/alsa/media_pipeline_backend_alsa.h" |
| #include "chromecast/media/cma/base/decoder_buffer_adapter.h" |
| #include "chromecast/media/cma/base/decoder_buffer_base.h" |
| #include "chromecast/public/media/cast_decoder_buffer.h" |
| #include "media/base/audio_buffer.h" |
| #include "media/base/audio_bus.h" |
| #include "media/base/channel_layout.h" |
| #include "media/base/decoder_buffer.h" |
| #include "media/base/sample_format.h" |
| #include "media/filters/audio_renderer_algorithm.h" |
| |
| #define TRACE_FUNCTION_ENTRY0() TRACE_EVENT0("cma", __FUNCTION__) |
| |
| #define TRACE_FUNCTION_ENTRY1(arg1) \ |
| TRACE_EVENT1("cma", __FUNCTION__, #arg1, arg1) |
| |
| #define TRACE_FUNCTION_ENTRY2(arg1, arg2) \ |
| TRACE_EVENT2("cma", __FUNCTION__, #arg1, arg1, #arg2, arg2) |
| |
| namespace chromecast { |
| namespace media { |
| |
| namespace { |
| |
| const int kNumChannels = 2; |
| const int kBitsPerSample = 32; |
| const int kDefaultFramesPerBuffer = 1024; |
| const int kSilenceBufferFrames = 2048; |
| const int kMaxOutputMs = 20; |
| const int kMillisecondsPerSecond = 1000; |
| |
| const double kPlaybackRateEpsilon = 0.001; |
| |
| const CastAudioDecoder::OutputFormat kDecoderSampleFormat = |
| CastAudioDecoder::kOutputPlanarFloat; |
| |
| const int64_t kInvalidTimestamp = std::numeric_limits<int64_t>::min(); |
| |
| const int64_t kNoPendingOutput = -1; |
| |
| } // namespace |
| |
| AudioDecoderAlsa::RateShifterInfo::RateShifterInfo(float playback_rate) |
| : rate(playback_rate), input_frames(0), output_frames(0) {} |
| |
| AudioDecoderAlsa::AudioDecoderAlsa(MediaPipelineBackendAlsa* backend) |
| : backend_(backend), |
| task_runner_(backend->GetTaskRunner()), |
| delegate_(nullptr), |
| pending_buffer_complete_(false), |
| got_eos_(false), |
| pushed_eos_(false), |
| mixer_error_(false), |
| rate_shifter_output_( |
| ::media::AudioBus::Create(kNumChannels, kDefaultFramesPerBuffer)), |
| current_pts_(kInvalidTimestamp), |
| pending_output_frames_(kNoPendingOutput), |
| volume_multiplier_(1.0f), |
| weak_factory_(this) { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(backend_); |
| DCHECK(task_runner_.get()); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| } |
| |
| AudioDecoderAlsa::~AudioDecoderAlsa() { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| } |
| |
| void AudioDecoderAlsa::SetDelegate( |
| MediaPipelineBackend::Decoder::Delegate* delegate) { |
| DCHECK(delegate); |
| delegate_ = delegate; |
| } |
| |
| void AudioDecoderAlsa::Initialize() { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(delegate_); |
| stats_ = Statistics(); |
| pending_buffer_complete_ = false; |
| got_eos_ = false; |
| pushed_eos_ = false; |
| current_pts_ = kInvalidTimestamp; |
| pending_output_frames_ = kNoPendingOutput; |
| |
| last_mixer_delay_.timestamp_microseconds = kInvalidTimestamp; |
| last_mixer_delay_.delay_microseconds = 0; |
| } |
| |
| bool AudioDecoderAlsa::Start(int64_t start_pts) { |
| TRACE_FUNCTION_ENTRY0(); |
| current_pts_ = start_pts; |
| DCHECK(IsValidConfig(config_)); |
| mixer_input_.reset(new StreamMixerAlsaInput(this, config_.samples_per_second, |
| backend_->Primary(), |
| backend_->DeviceId())); |
| mixer_input_->SetVolumeMultiplier(volume_multiplier_); |
| // Create decoder_ if necessary. This can happen if Stop() was called, and |
| // SetConfig() was not called since then. |
| if (!decoder_) { |
| CreateDecoder(); |
| } |
| if (!rate_shifter_) { |
| CreateRateShifter(config_.samples_per_second); |
| } |
| return true; |
| } |
| |
| void AudioDecoderAlsa::Stop() { |
| TRACE_FUNCTION_ENTRY0(); |
| decoder_.reset(); |
| mixer_input_.reset(); |
| rate_shifter_.reset(); |
| weak_factory_.InvalidateWeakPtrs(); |
| |
| Initialize(); |
| } |
| |
| bool AudioDecoderAlsa::Pause() { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(mixer_input_); |
| mixer_input_->SetPaused(true); |
| return true; |
| } |
| |
| bool AudioDecoderAlsa::Resume() { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(mixer_input_); |
| mixer_input_->SetPaused(false); |
| return true; |
| } |
| |
| bool AudioDecoderAlsa::SetPlaybackRate(float rate) { |
| if (std::abs(rate - 1.0) < kPlaybackRateEpsilon) { |
| // AudioRendererAlgorithm treats values close to 1 as exactly 1. |
| rate = 1.0f; |
| } |
| LOG(INFO) << "SetPlaybackRate to " << rate; |
| |
| // Remove info for rates that have no pending output left. |
| while (!rate_shifter_info_.empty()) { |
| RateShifterInfo* rate_info = &rate_shifter_info_.back(); |
| int64_t possible_output_frames = rate_info->input_frames / rate_info->rate; |
| DCHECK_GE(possible_output_frames, rate_info->output_frames); |
| if (rate_info->output_frames == possible_output_frames) { |
| rate_shifter_info_.pop_back(); |
| } else { |
| break; |
| } |
| } |
| |
| rate_shifter_info_.push_back(RateShifterInfo(rate)); |
| return true; |
| } |
| |
| AudioDecoderAlsa::BufferStatus AudioDecoderAlsa::PushBuffer( |
| CastDecoderBuffer* buffer) { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| DCHECK(buffer); |
| DCHECK(!got_eos_); |
| DCHECK(!mixer_error_); |
| DCHECK(!pending_buffer_complete_); |
| |
| uint64_t input_bytes = buffer->end_of_stream() ? 0 : buffer->data_size(); |
| scoped_refptr<DecoderBufferBase> buffer_base( |
| static_cast<DecoderBufferBase*>(buffer)); |
| if (!buffer->end_of_stream()) { |
| current_pts_ = buffer->timestamp(); |
| } |
| |
| // If the buffer is already decoded, do not attempt to decode. Call |
| // OnBufferDecoded asynchronously on the main thread. |
| if (BypassDecoder()) { |
| DCHECK(!decoder_); |
| task_runner_->PostTask( |
| FROM_HERE, |
| base::Bind(&AudioDecoderAlsa::OnBufferDecoded, |
| weak_factory_.GetWeakPtr(), input_bytes, |
| CastAudioDecoder::Status::kDecodeOk, buffer_base)); |
| return MediaPipelineBackendAlsa::kBufferPending; |
| } |
| |
| DCHECK(decoder_); |
| // Decode the buffer. |
| decoder_->Decode(buffer_base, |
| base::Bind(&AudioDecoderAlsa::OnBufferDecoded, |
| weak_factory_.GetWeakPtr(), |
| input_bytes)); |
| return MediaPipelineBackendAlsa::kBufferPending; |
| } |
| |
| void AudioDecoderAlsa::UpdateStatistics(Statistics delta) { |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| stats_.decoded_bytes += delta.decoded_bytes; |
| } |
| |
| void AudioDecoderAlsa::GetStatistics(Statistics* stats) { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(stats); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| *stats = stats_; |
| } |
| |
| bool AudioDecoderAlsa::SetConfig(const AudioConfig& config) { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| if (!IsValidConfig(config)) { |
| LOG(ERROR) << "Invalid audio config passed to SetConfig"; |
| return false; |
| } |
| |
| bool changed_sample_rate = |
| (config.samples_per_second != config_.samples_per_second); |
| |
| if (!rate_shifter_ || changed_sample_rate) { |
| CreateRateShifter(config.samples_per_second); |
| } |
| |
| if (mixer_input_ && changed_sample_rate) { |
| // Destroy the old input first to ensure that the mixer output sample rate |
| // is updated. |
| mixer_input_.reset(); |
| mixer_input_.reset(new StreamMixerAlsaInput(this, config.samples_per_second, |
| backend_->Primary(), |
| backend_->DeviceId())); |
| mixer_input_->SetVolumeMultiplier(volume_multiplier_); |
| pending_output_frames_ = kNoPendingOutput; |
| } |
| |
| config_ = config; |
| decoder_.reset(); |
| CreateDecoder(); |
| |
| if (pending_buffer_complete_ && changed_sample_rate) { |
| pending_buffer_complete_ = false; |
| delegate_->OnPushBufferComplete(MediaPipelineBackendAlsa::kBufferSuccess); |
| } |
| return true; |
| } |
| |
| void AudioDecoderAlsa::CreateDecoder() { |
| DCHECK(!decoder_); |
| DCHECK(IsValidConfig(config_)); |
| |
| // No need to create a decoder if the samples are already decoded. |
| if (BypassDecoder()) { |
| LOG(INFO) << "Data is not coded. Decoder will not be used."; |
| return; |
| } |
| |
| // Create a decoder. |
| decoder_ = CastAudioDecoder::Create( |
| task_runner_, |
| config_, |
| kDecoderSampleFormat, |
| base::Bind(&AudioDecoderAlsa::OnDecoderInitialized, |
| weak_factory_.GetWeakPtr())); |
| } |
| |
| void AudioDecoderAlsa::CreateRateShifter(int samples_per_second) { |
| rate_shifter_info_.clear(); |
| rate_shifter_info_.push_back(RateShifterInfo(1.0f)); |
| |
| rate_shifter_.reset(new ::media::AudioRendererAlgorithm()); |
| rate_shifter_->Initialize(::media::AudioParameters( |
| ::media::AudioParameters::AUDIO_PCM_LINEAR, |
| ::media::CHANNEL_LAYOUT_STEREO, samples_per_second, kBitsPerSample, |
| kDefaultFramesPerBuffer)); |
| } |
| |
| bool AudioDecoderAlsa::SetVolume(float multiplier) { |
| TRACE_FUNCTION_ENTRY1(multiplier); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| volume_multiplier_ = multiplier; |
| if (mixer_input_) |
| mixer_input_->SetVolumeMultiplier(volume_multiplier_); |
| return true; |
| } |
| |
| AudioDecoderAlsa::RenderingDelay AudioDecoderAlsa::GetRenderingDelay() { |
| TRACE_FUNCTION_ENTRY0(); |
| AudioDecoderAlsa::RenderingDelay delay = last_mixer_delay_; |
| if (delay.timestamp_microseconds != kInvalidTimestamp) { |
| double usec_per_sample = 1000000.0 / config_.samples_per_second; |
| |
| // Account for data that has been queued in the rate shifters. |
| for (const RateShifterInfo& info : rate_shifter_info_) { |
| double queued_output_frames = |
| (info.input_frames / info.rate) - info.output_frames; |
| delay.delay_microseconds += queued_output_frames * usec_per_sample; |
| } |
| |
| // Account for data that is in the process of being pushed to the mixer. |
| if (pending_output_frames_ != kNoPendingOutput) { |
| delay.delay_microseconds += pending_output_frames_ * usec_per_sample; |
| } |
| } |
| |
| return delay; |
| } |
| |
| void AudioDecoderAlsa::OnDecoderInitialized(bool success) { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| LOG(INFO) << "Decoder initialization was " |
| << (success ? "successful" : "unsuccessful"); |
| if (!success) |
| delegate_->OnDecoderError(); |
| } |
| |
| void AudioDecoderAlsa::OnBufferDecoded( |
| uint64_t input_bytes, |
| CastAudioDecoder::Status status, |
| const scoped_refptr<DecoderBufferBase>& decoded) { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| DCHECK(!got_eos_); |
| DCHECK(!pending_buffer_complete_); |
| DCHECK(rate_shifter_); |
| |
| if (status == CastAudioDecoder::Status::kDecodeError) { |
| LOG(ERROR) << "Decode error"; |
| delegate_->OnPushBufferComplete(MediaPipelineBackendAlsa::kBufferFailed); |
| return; |
| } |
| if (mixer_error_) { |
| delegate_->OnPushBufferComplete(MediaPipelineBackendAlsa::kBufferFailed); |
| return; |
| } |
| |
| Statistics delta; |
| delta.decoded_bytes = input_bytes; |
| UpdateStatistics(delta); |
| |
| pending_buffer_complete_ = true; |
| if (decoded->end_of_stream()) { |
| got_eos_ = true; |
| } else { |
| int input_frames = decoded->data_size() / (kNumChannels * sizeof(float)); |
| |
| DCHECK(!rate_shifter_info_.empty()); |
| RateShifterInfo* rate_info = &rate_shifter_info_.front(); |
| // Bypass rate shifter if the rate is 1.0, and there are no frames queued |
| // in the rate shifter. |
| if (rate_info->rate == 1.0 && rate_shifter_->frames_buffered() == 0 && |
| pending_output_frames_ == kNoPendingOutput && |
| rate_shifter_info_.size() == 1) { |
| DCHECK_EQ(rate_info->output_frames, rate_info->input_frames); |
| pending_output_frames_ = input_frames; |
| if (got_eos_) { |
| DCHECK(!pushed_eos_); |
| pushed_eos_ = true; |
| } |
| mixer_input_->WritePcm(decoded); |
| return; |
| } |
| |
| // Otherwise, queue data into the rate shifter, and then try to push the |
| // rate-shifted data. |
| const uint8_t* channels[kNumChannels] = { |
| decoded->data(), decoded->data() + input_frames * sizeof(float)}; |
| scoped_refptr<::media::AudioBuffer> buffer = ::media::AudioBuffer::CopyFrom( |
| ::media::kSampleFormatPlanarF32, ::media::CHANNEL_LAYOUT_STEREO, |
| kNumChannels, config_.samples_per_second, input_frames, channels, |
| base::TimeDelta()); |
| rate_shifter_->EnqueueBuffer(buffer); |
| rate_shifter_info_.back().input_frames += input_frames; |
| } |
| |
| PushRateShifted(); |
| DCHECK(!rate_shifter_info_.empty()); |
| CheckBufferComplete(); |
| } |
| |
| void AudioDecoderAlsa::CheckBufferComplete() { |
| if (!pending_buffer_complete_) { |
| return; |
| } |
| |
| bool rate_shifter_queue_full = rate_shifter_->IsQueueFull(); |
| DCHECK(!rate_shifter_info_.empty()); |
| if (rate_shifter_info_.front().rate == 1.0) { |
| // If the current rate is 1.0, drain any data in the rate shifter before |
| // calling PushBufferComplete, so that the next PushBuffer call can skip the |
| // rate shifter entirely. |
| rate_shifter_queue_full = (rate_shifter_->frames_buffered() > 0 || |
| pending_output_frames_ != kNoPendingOutput); |
| } |
| |
| if (pushed_eos_ || !rate_shifter_queue_full) { |
| pending_buffer_complete_ = false; |
| delegate_->OnPushBufferComplete(MediaPipelineBackendAlsa::kBufferSuccess); |
| } |
| } |
| |
| void AudioDecoderAlsa::PushRateShifted() { |
| DCHECK(mixer_input_); |
| |
| if (pushed_eos_ || pending_output_frames_ != kNoPendingOutput) { |
| return; |
| } |
| |
| if (got_eos_) { |
| // Push some silence into the rate shifter so we can get out any remaining |
| // rate-shifted data. |
| rate_shifter_->EnqueueBuffer(::media::AudioBuffer::CreateEmptyBuffer( |
| ::media::CHANNEL_LAYOUT_STEREO, kNumChannels, |
| config_.samples_per_second, kSilenceBufferFrames, base::TimeDelta())); |
| } |
| |
| DCHECK(!rate_shifter_info_.empty()); |
| RateShifterInfo* rate_info = &rate_shifter_info_.front(); |
| int64_t possible_output_frames = rate_info->input_frames / rate_info->rate; |
| DCHECK_GE(possible_output_frames, rate_info->output_frames); |
| |
| int desired_output_frames = possible_output_frames - rate_info->output_frames; |
| if (desired_output_frames == 0) { |
| if (got_eos_) { |
| DCHECK(!pushed_eos_); |
| pending_output_frames_ = 0; |
| pushed_eos_ = true; |
| |
| scoped_refptr<DecoderBufferBase> eos_buffer( |
| new DecoderBufferAdapter(::media::DecoderBuffer::CreateEOSBuffer())); |
| mixer_input_->WritePcm(eos_buffer); |
| } |
| return; |
| } |
| // Don't push too many frames at a time. |
| desired_output_frames = std::min( |
| desired_output_frames, |
| config_.samples_per_second * kMaxOutputMs / kMillisecondsPerSecond); |
| |
| if (desired_output_frames > rate_shifter_output_->frames()) { |
| rate_shifter_output_ = |
| ::media::AudioBus::Create(kNumChannels, desired_output_frames); |
| } |
| |
| int out_frames = rate_shifter_->FillBuffer( |
| rate_shifter_output_.get(), 0, desired_output_frames, rate_info->rate); |
| if (out_frames <= 0) { |
| return; |
| } |
| |
| rate_info->output_frames += out_frames; |
| DCHECK_GE(possible_output_frames, rate_info->output_frames); |
| |
| int channel_data_size = out_frames * sizeof(float); |
| scoped_refptr<DecoderBufferBase> output_buffer(new DecoderBufferAdapter( |
| new ::media::DecoderBuffer(channel_data_size * kNumChannels))); |
| for (int c = 0; c < kNumChannels; ++c) { |
| memcpy(output_buffer->writable_data() + c * channel_data_size, |
| rate_shifter_output_->channel(c), channel_data_size); |
| } |
| pending_output_frames_ = out_frames; |
| mixer_input_->WritePcm(output_buffer); |
| |
| if (rate_shifter_info_.size() > 1 && |
| rate_info->output_frames == possible_output_frames) { |
| double remaining_input_frames = |
| rate_info->input_frames - (rate_info->output_frames * rate_info->rate); |
| rate_shifter_info_.pop_front(); |
| |
| rate_info = &rate_shifter_info_.front(); |
| LOG(INFO) << "New playback rate in effect: " << rate_info->rate; |
| rate_info->input_frames += remaining_input_frames; |
| DCHECK_EQ(0, rate_info->output_frames); |
| |
| // If new playback rate is 1.0, clear out 'extra' data in the rate shifter. |
| // When doing rate shifting, the rate shifter queue holds data after it has |
| // been logically played; once we switch to passthrough mode (rate == 1.0), |
| // that old data needs to be cleared out. |
| if (rate_info->rate == 1.0) { |
| int extra_frames = rate_shifter_->frames_buffered() - |
| static_cast<int>(rate_info->input_frames); |
| if (extra_frames > 0) { |
| // Clear out extra buffered data. |
| std::unique_ptr<::media::AudioBus> dropped = |
| ::media::AudioBus::Create(kNumChannels, extra_frames); |
| int cleared_frames = |
| rate_shifter_->FillBuffer(dropped.get(), 0, extra_frames, 1.0f); |
| DCHECK_EQ(extra_frames, cleared_frames); |
| } |
| rate_info->input_frames = rate_shifter_->frames_buffered(); |
| } |
| } |
| } |
| |
| bool AudioDecoderAlsa::BypassDecoder() const { |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| // The mixer input requires planar float PCM data. |
| return (config_.codec == kCodecPCM && |
| config_.sample_format == kSampleFormatPlanarF32); |
| } |
| |
| void AudioDecoderAlsa::OnWritePcmCompletion(BufferStatus status, |
| const RenderingDelay& delay) { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| DCHECK_EQ(MediaPipelineBackendAlsa::kBufferSuccess, status); |
| pending_output_frames_ = kNoPendingOutput; |
| last_mixer_delay_ = delay; |
| |
| task_runner_->PostTask(FROM_HERE, base::Bind(&AudioDecoderAlsa::PushMorePcm, |
| weak_factory_.GetWeakPtr())); |
| } |
| |
| void AudioDecoderAlsa::PushMorePcm() { |
| PushRateShifted(); |
| |
| DCHECK(!rate_shifter_info_.empty()); |
| CheckBufferComplete(); |
| |
| if (pushed_eos_) { |
| delegate_->OnEndOfStream(); |
| } |
| } |
| |
| void AudioDecoderAlsa::OnMixerError(MixerError error) { |
| TRACE_FUNCTION_ENTRY0(); |
| DCHECK(task_runner_->BelongsToCurrentThread()); |
| if (error != MixerError::kInputIgnored) |
| LOG(ERROR) << "Mixer error occurred."; |
| mixer_error_ = true; |
| delegate_->OnDecoderError(); |
| } |
| |
| } // namespace media |
| } // namespace chromecast |