AudioPlaybackThread.cpp
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/**
* @file
* @brief Source file for AudioPlaybackThread class
* @author Duzy Chan <code@duzy.info>
* @author Jonathan Thomas <jonathan@openshot.org> *
*
* @section LICENSE
*
* Copyright (c) 2008-2014 OpenShot Studios, LLC
* <http://www.openshotstudios.com/>. This file is part of
* OpenShot Library (libopenshot), an open-source project dedicated to
* delivering high quality video editing and animation solutions to the
* world. For more information visit <http://www.openshot.org/>.
*
* OpenShot Library (libopenshot) is free software: you can redistribute it
* and/or modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* OpenShot Library (libopenshot) is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
*/
#include "../../include/Qt/AudioPlaybackThread.h"
namespace openshot
{
// Global reference to device manager
AudioDeviceManagerSingleton *AudioDeviceManagerSingleton::m_pInstance = NULL;
// Create or Get an instance of the device manager singleton
AudioDeviceManagerSingleton *AudioDeviceManagerSingleton::Instance(int numChannels)
{
if (!m_pInstance) {
// Create the actual instance of device manager only once
m_pInstance = new AudioDeviceManagerSingleton;
// Initialize audio device only 1 time
m_pInstance->audioDeviceManager.initialise (
0, /* number of input channels */
numChannels, /* number of output channels */
0, /* no XML settings.. */
true /* select default device on failure */);
}
return m_pInstance;
}
// Close audio device
void AudioDeviceManagerSingleton::CloseAudioDevice()
{
// Close Audio Device
audioDeviceManager.closeAudioDevice();
audioDeviceManager.removeAllChangeListeners();
audioDeviceManager.dispatchPendingMessages();
}
// Constructor
AudioPlaybackThread::AudioPlaybackThread()
: Thread("audio-playback")
, player()
, transport()
, mixer()
, source(NULL)
, sampleRate(0.0)
, numChannels(0)
, buffer_size(12000)
, is_playing(false)
, time_thread("audio-buffer")
{
}
// Destructor
AudioPlaybackThread::~AudioPlaybackThread()
{
}
// Set the reader object
void AudioPlaybackThread::Reader(ReaderBase *reader) {
if (source)
source->Reader(reader);
else {
// Create new audio source reader
source = new AudioReaderSource(reader, 1, buffer_size);
source->setLooping(true); // prevent this source from terminating when it reaches the end
}
// Set local vars
sampleRate = reader->info.sample_rate;
numChannels = reader->info.channels;
// TODO: Update transport or audio source's sample rate, incase the sample rate
// is different than the original Reader
// Mark as 'playing'
Play();
}
// Get the current frame object (which is filling the buffer)
std::shared_ptr<Frame> AudioPlaybackThread::getFrame()
{
if (source) return source->getFrame();
return std::shared_ptr<Frame>();
}
// Get the currently playing frame number
int64_t AudioPlaybackThread::getCurrentFramePosition()
{
return source ? source->getEstimatedFrame() : 0;
}
// Seek the audio thread
void AudioPlaybackThread::Seek(int64_t new_position)
{
source->Seek(new_position);
}
// Play the audio
void AudioPlaybackThread::Play() {
// Start playing
is_playing = true;
}
// Stop the audio
void AudioPlaybackThread::Stop() {
// Stop playing
is_playing = false;
}
// Start audio thread
void AudioPlaybackThread::run()
{
while (!threadShouldExit())
{
if (source && !transport.isPlaying() && is_playing) {
// Start new audio device (or get existing one)
// Add callback
AudioDeviceManagerSingleton::Instance(numChannels)->audioDeviceManager.addAudioCallback(&player);
// Create TimeSliceThread for audio buffering
time_thread.startThread();
// Connect source to transport
transport.setSource(
source,
buffer_size, // tells it to buffer this many samples ahead
&time_thread,
sampleRate,
numChannels);
transport.setPosition(0);
transport.setGain(1.0);
// Connect transport to mixer and player
mixer.addInputSource(&transport, false);
player.setSource(&mixer);
// Start the transport
transport.start();
while (!threadShouldExit() && transport.isPlaying() && is_playing)
usleep(2500);
// Stop audio and shutdown transport
Stop();
transport.stop();
// Kill previous audio
transport.setSource(NULL);
player.setSource(NULL);
AudioDeviceManagerSingleton::Instance(0)->audioDeviceManager.removeAudioCallback(&player);
// Remove source
delete source;
source = NULL;
// Stop time slice thread
time_thread.stopThread(-1);
}
}
}
}
openshot::AudioReaderSource::Seek
void Seek(int64_t new_position)
Seek to a specific frame.
Definition: AudioReaderSource.h:137
openshot
This namespace is the default namespace for all code in the openshot library.
Definition: AudioBufferSource.h:45
openshot::AudioDeviceManagerSingleton::audioDeviceManager
AudioDeviceManager audioDeviceManager
Public device manager property.
Definition: AudioPlaybackThread.h:70
openshot::AudioReaderSource::setLooping
void setLooping(bool shouldLoop)
Set if this audio source should repeat when it reaches the end.
Definition: AudioReaderSource.cpp:280
openshot::AudioReaderSource::getEstimatedFrame
int64_t getEstimatedFrame() const
Get the estimate frame that is playing at this moment.
Definition: AudioReaderSource.h:124
openshot::AudioDeviceManagerSingleton
Singleton wrapper for AudioDeviceManager (to prevent multiple instances).
Definition: AudioPlaybackThread.h:57
openshot::AudioDeviceManagerSingleton::Instance
static AudioDeviceManagerSingleton * Instance(int numChannels)
Create or get an instance of this singleton (invoke the class with this method)
Definition: AudioPlaybackThread.cpp:38
openshot::AudioReaderSource::Reader
void Reader(ReaderBase *audio_reader)
Set Reader.
Definition: AudioReaderSource.h:132
openshot::AudioReaderSource::getFrame
std::shared_ptr< Frame > getFrame() const
Return the current frame object.
Definition: AudioReaderSource.h:121
openshot::AudioDeviceManagerSingleton::CloseAudioDevice
void CloseAudioDevice()
Close audio device.
Definition: AudioPlaybackThread.cpp:56