OpenShot Library | libopenshot  0.2.5
AudioPlaybackThread.cpp
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1 /**
2  * @file
3  * @brief Source file for AudioPlaybackThread class
4  * @author Duzy Chan <code@duzy.info>
5  * @author Jonathan Thomas <jonathan@openshot.org> *
6  *
7  * @ref License
8  */
9 
10 /* LICENSE
11  *
12  * Copyright (c) 2008-2019 OpenShot Studios, LLC
13  * <http://www.openshotstudios.com/>. This file is part of
14  * OpenShot Library (libopenshot), an open-source project dedicated to
15  * delivering high quality video editing and animation solutions to the
16  * world. For more information visit <http://www.openshot.org/>.
17  *
18  * OpenShot Library (libopenshot) is free software: you can redistribute it
19  * and/or modify it under the terms of the GNU Lesser General Public License
20  * as published by the Free Software Foundation, either version 3 of the
21  * License, or (at your option) any later version.
22  *
23  * OpenShot Library (libopenshot) is distributed in the hope that it will be
24  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26  * GNU Lesser General Public License for more details.
27  *
28  * You should have received a copy of the GNU Lesser General Public License
29  * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
30  */
31 
32 #include "../../include/Qt/AudioPlaybackThread.h"
33 
34 namespace openshot
35 {
36 
37  // Global reference to device manager
38  AudioDeviceManagerSingleton *AudioDeviceManagerSingleton::m_pInstance = NULL;
39 
40  // Create or Get an instance of the device manager singleton
42  {
43  if (!m_pInstance) {
44  // Create the actual instance of device manager only once
45  m_pInstance = new AudioDeviceManagerSingleton;
46 
47  // Get preferred audio device name (if any)
48  juce::String preferred_audio_device = juce::String(Settings::Instance()->PLAYBACK_AUDIO_DEVICE_NAME.c_str());
49 
50  // Initialize audio device only 1 time
51  juce::String audio_error = m_pInstance->audioDeviceManager.initialise (
52  0, /* number of input channels */
53  2, /* number of output channels */
54  0, /* no XML settings.. */
55  true, /* select default device on failure */
56  preferred_audio_device /* preferredDefaultDeviceName */);
57 
58  // Persist any errors detected
59  if (audio_error.isNotEmpty()) {
60  m_pInstance->initialise_error = audio_error.toRawUTF8();
61  } else {
62  m_pInstance->initialise_error = "";
63  }
64 
65  // Get all audio device names
66  for (int i = 0; i < m_pInstance->audioDeviceManager.getAvailableDeviceTypes().size(); ++i)
67  {
68  const AudioIODeviceType* t = m_pInstance->audioDeviceManager.getAvailableDeviceTypes()[i];
69  const juce::StringArray deviceNames = t->getDeviceNames ();
70 
71  for (int j = 0; j < deviceNames.size (); ++j )
72  {
73  juce::String deviceName = deviceNames[j];
74  juce::String typeName = t->getTypeName();
75  openshot::AudioDeviceInfo deviceInfo = {deviceName.toRawUTF8(), typeName.toRawUTF8()};
76  m_pInstance->audio_device_names.push_back(deviceInfo);
77  }
78  }
79  }
80 
81  return m_pInstance;
82  }
83 
84  // Close audio device
86  {
87  // Close Audio Device
88  audioDeviceManager.closeAudioDevice();
89  audioDeviceManager.removeAllChangeListeners();
90  audioDeviceManager.dispatchPendingMessages();
91  }
92 
93  // Constructor
94  AudioPlaybackThread::AudioPlaybackThread()
95  : juce::Thread("audio-playback")
96  , player()
97  , transport()
98  , mixer()
99  , source(NULL)
100  , sampleRate(0.0)
101  , numChannels(0)
102  , buffer_size(12000)
103  , is_playing(false)
104  , time_thread("audio-buffer")
105  {
106  }
107 
108  // Destructor
109  AudioPlaybackThread::~AudioPlaybackThread()
110  {
111  }
112 
113  // Set the reader object
114  void AudioPlaybackThread::Reader(openshot::ReaderBase *reader) {
115  if (source)
116  source->Reader(reader);
117  else {
118  // Create new audio source reader
119  source = new AudioReaderSource(reader, 1, buffer_size);
120  source->setLooping(true); // prevent this source from terminating when it reaches the end
121  }
122 
123  // Set local vars
124  sampleRate = reader->info.sample_rate;
125  numChannels = reader->info.channels;
126 
127  // TODO: Update transport or audio source's sample rate, incase the sample rate
128  // is different than the original Reader
129 
130  // Mark as 'playing'
131  Play();
132  }
133 
134  // Get the current frame object (which is filling the buffer)
135  std::shared_ptr<openshot::Frame> AudioPlaybackThread::getFrame()
136  {
137  if (source) return source->getFrame();
138  return std::shared_ptr<openshot::Frame>();
139  }
140 
141  // Get the currently playing frame number
142  int64_t AudioPlaybackThread::getCurrentFramePosition()
143  {
144  return source ? source->getEstimatedFrame() : 0;
145  }
146 
147  // Seek the audio thread
148  void AudioPlaybackThread::Seek(int64_t new_position)
149  {
150  source->Seek(new_position);
151  }
152 
153  // Play the audio
154  void AudioPlaybackThread::Play() {
155  // Start playing
156  is_playing = true;
157  }
158 
159  // Stop the audio
160  void AudioPlaybackThread::Stop() {
161  // Stop playing
162  is_playing = false;
163  }
164 
165  // Start audio thread
166  void AudioPlaybackThread::run()
167  {
168  while (!threadShouldExit())
169  {
170  if (source && !transport.isPlaying() && is_playing) {
171 
172  // Start new audio device (or get existing one)
173  // Add callback
174  AudioDeviceManagerSingleton::Instance()->audioDeviceManager.addAudioCallback(&player);
175 
176  // Create TimeSliceThread for audio buffering
177  time_thread.startThread();
178 
179  // Connect source to transport
180  transport.setSource(
181  source,
182  buffer_size, // tells it to buffer this many samples ahead
183  &time_thread,
184  sampleRate,
185  numChannels);
186  transport.setPosition(0);
187  transport.setGain(1.0);
188 
189  // Connect transport to mixer and player
190  mixer.addInputSource(&transport, false);
191  player.setSource(&mixer);
192 
193  // Start the transport
194  transport.start();
195 
196  while (!threadShouldExit() && transport.isPlaying() && is_playing)
197  usleep(2500);
198 
199  // Stop audio and shutdown transport
200  Stop();
201  transport.stop();
202 
203  // Kill previous audio
204  transport.setSource(NULL);
205 
206  player.setSource(NULL);
207  AudioDeviceManagerSingleton::Instance()->audioDeviceManager.removeAudioCallback(&player);
208 
209  // Remove source
210  delete source;
211  source = NULL;
212 
213  // Stop time slice thread
214  time_thread.stopThread(-1);
215  }
216  }
217 
218  }
219 }
openshot::AudioReaderSource::Seek
void Seek(int64_t new_position)
Seek to a specific frame.
Definition: AudioReaderSource.h:130
openshot::AudioDeviceManagerSingleton::initialise_error
std::string initialise_error
Error found during JUCE initialise method.
Definition: AudioPlaybackThread.h:69
openshot::ReaderInfo::sample_rate
int sample_rate
The number of audio samples per second (44100 is a common sample rate)
Definition: ReaderBase.h:82
openshot::AudioDeviceInfo
Definition: AudioDeviceInfo.h:41
openshot
This namespace is the default namespace for all code in the openshot library.
Definition: AudioBufferSource.h:38
openshot::AudioDeviceManagerSingleton::audioDeviceManager
AudioDeviceManager audioDeviceManager
Public device manager property.
Definition: AudioPlaybackThread.h:78
openshot::AudioReaderSource::setLooping
void setLooping(bool shouldLoop)
Set if this audio source should repeat when it reaches the end.
Definition: AudioReaderSource.cpp:283
openshot::AudioReaderSource::getEstimatedFrame
int64_t getEstimatedFrame() const
Get the estimate frame that is playing at this moment.
Definition: AudioReaderSource.h:117
openshot::AudioDeviceManagerSingleton::Instance
static AudioDeviceManagerSingleton * Instance()
Override with no channels and no preferred audio device.
Definition: AudioPlaybackThread.cpp:41
openshot::ReaderBase::info
openshot::ReaderInfo info
Information about the current media file.
Definition: ReaderBase.h:111
openshot::AudioDeviceManagerSingleton::audio_device_names
std::vector< openshot::AudioDeviceInfo > audio_device_names
List of valid audio device names.
Definition: AudioPlaybackThread.h:72
openshot::AudioDeviceManagerSingleton
Singleton wrapper for AudioDeviceManager (to prevent multiple instances).
Definition: AudioPlaybackThread.h:59
openshot::Settings::Instance
static Settings * Instance()
Create or get an instance of this logger singleton (invoke the class with this method)
Definition: Settings.cpp:41
openshot::AudioReaderSource::Reader
void Reader(ReaderBase *audio_reader)
Set Reader.
Definition: AudioReaderSource.h:125
openshot::AudioReaderSource::getFrame
std::shared_ptr< Frame > getFrame() const
Return the current frame object.
Definition: AudioReaderSource.h:114
openshot::AudioDeviceManagerSingleton::CloseAudioDevice
void CloseAudioDevice()
Close audio device.
Definition: AudioPlaybackThread.cpp:85
openshot::ReaderBase
This abstract class is the base class, used by all readers in libopenshot.
Definition: ReaderBase.h:97
openshot::ReaderInfo::channels
int channels
The number of audio channels used in the audio stream.
Definition: ReaderBase.h:83