OpenShot Library | libopenshot  0.2.2
AudioReaderSource.h
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1 /**
2  * @file
3  * @brief Header file for AudioReaderSource class
4  * @author Jonathan Thomas <jonathan@openshot.org>
5  *
6  * @section LICENSE
7  *
8  * Copyright (c) 2008-2014 OpenShot Studios, LLC
9  * <http://www.openshotstudios.com/>. This file is part of
10  * OpenShot Library (libopenshot), an open-source project dedicated to
11  * delivering high quality video editing and animation solutions to the
12  * world. For more information visit <http://www.openshot.org/>.
13  *
14  * OpenShot Library (libopenshot) is free software: you can redistribute it
15  * and/or modify it under the terms of the GNU Lesser General Public License
16  * as published by the Free Software Foundation, either version 3 of the
17  * License, or (at your option) any later version.
18  *
19  * OpenShot Library (libopenshot) is distributed in the hope that it will be
20  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22  * GNU Lesser General Public License for more details.
23  *
24  * You should have received a copy of the GNU Lesser General Public License
25  * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
26  */
27 
28 #ifndef OPENSHOT_AUDIOREADERSOURCE_H
29 #define OPENSHOT_AUDIOREADERSOURCE_H
30 
31 /// Do not include the juce unittest headers, because it collides with unittest++
32 #define __JUCE_UNITTEST_JUCEHEADER__
33 
34 #ifndef _NDEBUG
35  /// Define NO debug for JUCE on mac os
36  #define _NDEBUG
37 #endif
38 
39 #include <iomanip>
40 #include "JuceLibraryCode/JuceHeader.h"
41 #include "ReaderBase.h"
42 
43 using namespace std;
44 
45 /// This namespace is the default namespace for all code in the openshot library
46 namespace openshot
47 {
48 
49  /**
50  * @brief This class is used to expose any ReaderBase derived class as an AudioSource in JUCE.
51  *
52  * This allows any reader to play audio through JUCE (our audio framework).
53  */
54  class AudioReaderSource : public PositionableAudioSource
55  {
56  private:
57  int position; /// The position of the audio source (index of buffer)
58  bool repeat; /// Repeat the audio source when finished
59  int size; /// The size of the internal buffer
60  AudioSampleBuffer *buffer; /// The audio sample buffer
61  int speed; /// The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
62 
63  ReaderBase *reader; /// The reader to pull samples from
64  int64_t original_frame_number; /// The current frame to read from
65  int64_t frame_number; /// The current frame number
66  std::shared_ptr<Frame> frame; /// The current frame object that is being read
67  int64_t frame_position; /// The position of the current frame's buffer
68  double estimated_frame; /// The estimated frame position of the currently playing buffer
69  int estimated_samples_per_frame; /// The estimated samples per frame of video
70 
71  /// Get more samples from the reader
72  void GetMoreSamplesFromReader();
73 
74  /// Reverse an audio buffer (for backwards audio)
75  juce::AudioSampleBuffer* reverse_buffer(juce::AudioSampleBuffer* buffer);
76 
77  public:
78 
79  /// @brief Constructor that reads samples from a reader
80  /// @param audio_reader This reader provides constant samples from a ReaderBase derived class
81  /// @param starting_frame_number This is the frame number to start reading samples from the reader.
82  /// @param buffer_size The max number of samples to keep in the buffer at one time.
83  AudioReaderSource(ReaderBase *audio_reader, int64_t starting_frame_number, int buffer_size);
84 
85  /// Destructor
87 
88  /// @brief Get the next block of audio samples
89  /// @param info This struct informs us of which samples are needed next.
90  void getNextAudioBlock (const AudioSourceChannelInfo& info);
91 
92  /// Prepare to play this audio source
93  void prepareToPlay(int, double);
94 
95  /// Release all resources
96  void releaseResources();
97 
98  /// @brief Set the next read position of this source
99  /// @param newPosition The sample # to start reading from
100  void setNextReadPosition (int64 newPosition);
101 
102  /// Get the next read position of this source
103  int64 getNextReadPosition() const;
104 
105  /// Get the total length (in samples) of this audio source
106  int64 getTotalLength() const;
107 
108  /// Determines if this audio source should repeat when it reaches the end
109  bool isLooping() const;
110 
111  /// @brief Set if this audio source should repeat when it reaches the end
112  /// @param shouldLoop Determines if the audio source should repeat when it reaches the end
113  void setLooping (bool shouldLoop);
114 
115  /// Update the internal buffer used by this source
116  void setBuffer (AudioSampleBuffer *audio_buffer);
117 
118  const ReaderInfo & getReaderInfo() const { return reader->info; }
119 
120  /// Return the current frame object
121  std::shared_ptr<Frame> getFrame() const { return frame; }
122 
123  /// Get the estimate frame that is playing at this moment
124  int64_t getEstimatedFrame() const { return int64_t(estimated_frame); }
125 
126  /// Set Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
127  void setSpeed(int new_speed) { speed = new_speed; }
128  /// Get Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
129  int getSpeed() const { return speed; }
130 
131  /// Set Reader
132  void Reader(ReaderBase *audio_reader) { reader = audio_reader; }
133  /// Get Reader
134  ReaderBase* Reader() const { return reader; }
135 
136  /// Seek to a specific frame
137  void Seek(int64_t new_position) { frame_number = new_position; estimated_frame = new_position; }
138 
139  };
140 
141 }
142 
143 #endif
Header file for ReaderBase class.
std::shared_ptr< Frame > getFrame() const
Return the current frame object.
This abstract class is the base class, used by all readers in libopenshot.
Definition: ReaderBase.h:96
const ReaderInfo & getReaderInfo() const
void Seek(int64_t new_position)
Seek to a specific frame.
This struct contains info about a media file, such as height, width, frames per second, etc...
Definition: ReaderBase.h:59
void Reader(ReaderBase *audio_reader)
Set Reader.
This class is used to expose any ReaderBase derived class as an AudioSource in JUCE.
int getSpeed() const
Get Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
ReaderBase * Reader() const
Get Reader.
void setSpeed(int new_speed)
Set Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
int64_t getEstimatedFrame() const
Get the estimate frame that is playing at this moment.