This Section demonstrates how to use the Audio Manager API for audio capture session.
1. Get the AudioFactory and AudioManager instances
auto &audioFactory = audioFactory::getInstance();
auto audioManager = audioFactory.getAudioManager();
2. Check if Audio subsystem is ready
bool subSystemsStatus = audioManager->isSubsystemReady();
if (subSystemsStatus) {
std::cout << "Audio Subsystem is ready." << std::endl;
} else {
std::cout << "Audio Subsystem is NOT ready." << std::endl;
}
2.1 If Audio subsystem is not ready, wait for it to be ready
Make sure that Audio subsystem is ready for services like audio capture. If subsystem is not ready, wait unconditionally (or) until a timeout.
std::future<bool> f = audioManager->onSubsystemReady();
#if //Timeout based wait
if (f.wait_for(std::chrono::seconds(timeoutSec)) == std::future_status::timeout) {
std::cout << "operation timed out." << std::endl;
} else {
subSystemsStatus = f.get();
if (subSystemsStatus) {
std::cout << "Audio Subsystem is ready." << std::endl;
}
}
#else //Unconditional wait
subSystemsStatus = f.get();
if (subSystemsStatus) {
std::cout << "Audio Subsystem is ready." << std::endl;
} else {
std::cout << "Audio Subsystem is NOT ready." << std::endl;
}
#endif
3. Create an Audio Stream (Audio Capture Session)
void createStreamCallback(std::shared_ptr<IAudioStream> &stream, ErrorCode error)
{
if (error != ErrorCode::SUCCESS) {
std::cout << "createStream() returned with error " << static_cast<int>(error)
<< std::endl;
return;
}
std::cout << "createStream() succeeded." << std::endl;
audioCaptureStream = std::dynamic_pointer_cast<IAudioCaptureStream>(stream);
}
StreamConfig config;
config.type = StreamType::CAPTURE;
config.sampleRate = 48000;
config.format = AudioFormat::PCM_16BIT_SIGNED;
config.channelTypeMask = ChannelType::LEFT;
config.deviceTypes.emplace_back(DeviceType::DEVICE_TYPE_SPEAKER);
status = audioManager->createStream(config, createStreamCallback);
4. Allocate Stream Buffers for Capture Operation
auto streamBuffer = audioCaptureStream->getStreamBuffer();
if(streamBuffer != nullptr) {
bytesToRead = streamBuffer->getMinSize();
if(bytesToRead == 0) {
bytesToRead = streamBuffer->getMaxSize();
}
} else {
std::cout << "Failed to get Stream Buffer " << std::endl;
return EXIT_FAILURE;
}
5. Start read operation for the capture to Start
void readCallback(std::shared_ptr<IStreamBuffer> buffer, ErrorCode error)
{
uint32_t bytesWrittenToFile = 0;
if (error != ErrorCode::SUCCESS) {
std::cout << "read() returned with error " << static_cast<int>(error) << std::endl;
} else {
uint32_t size = buffer->getDataSize();
std::cout << "Successfully read " << size << " bytes" << std::endl;
}
buffer->reset();
return;
}
auto status = audioCaptureStream->read(streamBuffer, bytesToRead, readCallback);
if(status != telux::common::Status::SUCCESS) {
std::cout << "read() failed with error" << static_cast<int>(status) << std::endl;
} else {
std::cout << "Request to read stream sent" << std::endl;
}
6. Delete an Audio Stream (Audio Capture Session), once required bytes captured.
void deleteStreamCallback(ErrorCode error) {
if (error != ErrorCode::SUCCESS) {
std::cout << "deleteStream() returned with error " << static_cast<int>(error)
<< std::endl;
return;
}
std::cout << "deleteStream() succeeded." << std::endl;
audioCaptureStream.reset();
}
Status status = audioManager->deleteStream(
std::dynamic_pointer_cast<IAudioStream>(audioCaptureStream), deleteStreamCallback);
if (status != Status::SUCCESS) {
std::cout << "deleteStream failed with error" << static_cast<int>(status) << std::endl;
}