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Improve oboe latency estimation

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badaix 2020-01-25 14:32:39 +01:00
parent 5b9fc3d68d
commit 08de66fe70
2 changed files with 54 additions and 14 deletions
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60
client/player/oboe_player.cpp
View file

@ -26,10 +26,12 @@
using namespace std;
static constexpr auto LOG_TAG = "OboePlayer";
static constexpr double kDefaultLatency = 50;
OboePlayer::OboePlayer(const PcmDevice& pcmDevice, std::shared_ptr<Stream> stream) : Player(pcmDevice, stream), ms_(50), buff_size(0), pubStream_(stream)
OboePlayer::OboePlayer(const PcmDevice& pcmDevice, std::shared_ptr<Stream> stream) : Player(pcmDevice, stream)
{
LOG(DEBUG, LOG_TAG) << "Contructor\n";
oboe::AudioStreamBuilder builder;
// The builder set methods can be chained for convenience.
builder.setSharingMode(oboe::SharingMode::Exclusive)
@ -38,22 +40,62 @@ OboePlayer::OboePlayer(const PcmDevice& pcmDevice, std::shared_ptr<Stream> strea
->setSampleRate(stream->getFormat().rate)
->setFormat(oboe::AudioFormat::I16)
->setCallback(this)
//->setFramesPerCallback((20 * stream->getFormat().rate) / 1000)
->openManagedStream(out_stream_);
}
OboePlayer::~OboePlayer()
{
LOG(DEBUG, LOG_TAG) << "Destructor\n";
stop();
out_stream_->stop(std::chrono::nanoseconds(100ms).count());
}
oboe::DataCallbackResult OboePlayer::onAudioReady(oboe::AudioStream* oboeStream, void* audioData, int32_t numFrames)
double OboePlayer::getCurrentOutputLatencyMillis() const
{
int32_t buffer_fill_size = oboeStream->getBufferCapacityInFrames() - numFrames;
double delay_ms = static_cast<double>(buffer_fill_size) / stream_->getFormat().msRate();
chronos::usec delay(static_cast<int>(delay_ms * 1000.));
//LOG(INFO) << "onAudioReady frames: " << numFrames << ", capacity: " << oboeStream->getBufferCapacityInFrames() << ", size: " << oboeStream->getBufferSizeInFrames() << ", delay ms: " << delay_ms << "\n";
// if (!mIsLatencyDetectionSupported)
// return -1;
// Get the time that a known audio frame was presented for playing
auto result = out_stream_->getTimestamp(CLOCK_MONOTONIC);
double outputLatencyMillis = kDefaultLatency;
const int64_t kNanosPerMillisecond = 1000000;
if (result == oboe::Result::OK)
{
oboe::FrameTimestamp playedFrame = result.value();
// Get the write index for the next audio frame
int64_t writeIndex = out_stream_->getFramesWritten();
// Calculate the number of frames between our known frame and the write index
int64_t frameIndexDelta = writeIndex - playedFrame.position;
// Calculate the time which the next frame will be presented
int64_t frameTimeDelta = (frameIndexDelta * oboe::kNanosPerSecond) / (out_stream_->getSampleRate());
int64_t nextFramePresentationTime = playedFrame.timestamp + frameTimeDelta;
// Assume that the next frame will be written at the current time
using namespace std::chrono;
int64_t nextFrameWriteTime = duration_cast<nanoseconds>(steady_clock::now().time_since_epoch()).count();
// Calculate the latency
outputLatencyMillis = static_cast<double>(nextFramePresentationTime - nextFrameWriteTime) / kNanosPerMillisecond;
}
else
{
// LOG(ERROR, LOG_TAG) << "Error calculating latency: " << oboe::convertToText(result.error()) << "\n";
}
return outputLatencyMillis;
}
oboe::DataCallbackResult OboePlayer::onAudioReady(oboe::AudioStream* /*oboeStream*/, void* audioData, int32_t numFrames)
{
// int32_t buffer_fill_size = oboeStream->getBufferCapacityInFrames() - numFrames;
// double delay_ms = static_cast<double>(oboeStream->getBufferCapacityInFrames()) / stream_->getFormat().msRate();
// LOG(INFO, LOG_TAG) << "onAudioReady frames: " << numFrames << ", capacity: " << oboeStream->getBufferCapacityInFrames() << ", size: " <<
// oboeStream->getBufferSizeInFrames() << ", available: " << oboeStream->getAvailableFrames() << ", delay ms: " << delay_ms << "\n";
double output_latency = getCurrentOutputLatencyMillis();
// LOG(INFO, LOG_TAG) << "getCurrentOutputLatencyMillis: " << output_latency << "\n";
chronos::usec delay(static_cast<int>(output_latency * 1000.));
if (!stream_->getPlayerChunk(audioData, delay, numFrames))
{
@ -72,12 +114,14 @@ oboe::DataCallbackResult OboePlayer::onAudioReady(oboe::AudioStream* oboeStream,
void OboePlayer::start()
{
// Typically, start the stream after querying some stream information, as well as some input from the user
LOG(INFO, LOG_TAG) << "Start\n";
out_stream_->requestStart();
}
void OboePlayer::stop()
{
LOG(INFO, LOG_TAG) << "Stop\n";
out_stream_->requestStop();
}

8
client/player/oboe_player.hpp
View file

@ -40,16 +40,12 @@ public:
void stop() override;
protected:
oboe::DataCallbackResult onAudioReady(oboe::AudioStream *oboeStream, void *audioData, int32_t numFrames) override;
oboe::DataCallbackResult onAudioReady(oboe::AudioStream* oboeStream, void* audioData, int32_t numFrames) override;
double getCurrentOutputLatencyMillis() const;
void worker() override;
oboe::ManagedStream out_stream_;
size_t ms_;
size_t frames_;
size_t buff_size;
std::shared_ptr<Stream> pubStream_;
};