OpenShot Library | libopenshot 0.2.7
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 * @ref License
7 */
8
9/* LICENSE
10 *
11 * Copyright (c) 2008-2019 OpenShot Studios, LLC
12 * <http://www.openshotstudios.com/>. This file is part of
13 * OpenShot Library (libopenshot), an open-source project dedicated to
14 * delivering high quality video editing and animation solutions to the
15 * world. For more information visit <http://www.openshot.org/>.
16 *
17 * OpenShot Library (libopenshot) is free software: you can redistribute it
18 * and/or modify it under the terms of the GNU Lesser General Public License
19 * as published by the Free Software Foundation, either version 3 of the
20 * License, or (at your option) any later version.
21 *
22 * OpenShot Library (libopenshot) is distributed in the hope that it will be
23 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 * GNU Lesser General Public License for more details.
26 *
27 * You should have received a copy of the GNU Lesser General Public License
28 * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
29 */
30
31#ifndef OPENSHOT_AUDIOREADERSOURCE_H
32#define OPENSHOT_AUDIOREADERSOURCE_H
33
34#include <iomanip>
35#include "ReaderBase.h"
36#include <OpenShotAudio.h>
37
38/// This namespace is the default namespace for all code in the openshot library
39namespace openshot
40{
41
42 /**
43 * @brief This class is used to expose any ReaderBase derived class as an AudioSource in JUCE.
44 *
45 * This allows any reader to play audio through JUCE (our audio framework).
46 */
47 class AudioReaderSource : public juce::PositionableAudioSource
48 {
49 private:
50 int position; /// The position of the audio source (index of buffer)
51 bool repeat; /// Repeat the audio source when finished
52 int size; /// The size of the internal buffer
53 juce::AudioSampleBuffer *buffer; /// The audio sample buffer
54 int speed; /// The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
55
56 ReaderBase *reader; /// The reader to pull samples from
57 int64_t frame_number; /// The current frame number
58 std::shared_ptr<Frame> frame; /// The current frame object that is being read
59 int64_t frame_position; /// The position of the current frame's buffer
60 double estimated_frame; /// The estimated frame position of the currently playing buffer
61 int estimated_samples_per_frame; /// The estimated samples per frame of video
62
63 /// Get more samples from the reader
64 void GetMoreSamplesFromReader();
65
66 /// Reverse an audio buffer (for backwards audio)
67 juce::AudioSampleBuffer* reverse_buffer(juce::AudioSampleBuffer* buffer);
68
69 public:
70
71 /// @brief Constructor that reads samples from a reader
72 /// @param audio_reader This reader provides constant samples from a ReaderBase derived class
73 /// @param starting_frame_number This is the frame number to start reading samples from the reader.
74 /// @param buffer_size The max number of samples to keep in the buffer at one time.
75 AudioReaderSource(ReaderBase *audio_reader, int64_t starting_frame_number, int buffer_size);
76
77 /// Destructor
79
80 /// @brief Get the next block of audio samples
81 /// @param info This struct informs us of which samples are needed next.
82 void getNextAudioBlock (const juce::AudioSourceChannelInfo& info);
83
84 /// Prepare to play this audio source
85 void prepareToPlay(int, double);
86
87 /// Release all resources
88 void releaseResources();
89
90 /// @brief Set the next read position of this source
91 /// @param newPosition The sample # to start reading from
92 void setNextReadPosition (juce::int64 newPosition);
93
94 /// Get the next read position of this source
96
97 /// Get the total length (in samples) of this audio source
99
100 /// Determines if this audio source should repeat when it reaches the end
101 bool isLooping() const;
102
103 /// @brief Set if this audio source should repeat when it reaches the end
104 /// @param shouldLoop Determines if the audio source should repeat when it reaches the end
105 void setLooping (bool shouldLoop);
106
107 /// Update the internal buffer used by this source
108 void setBuffer (juce::AudioSampleBuffer *audio_buffer);
109
110 const ReaderInfo & getReaderInfo() const { return reader->info; }
111
112 /// Return the current frame object
113 std::shared_ptr<Frame> getFrame() const { return frame; }
114
115 /// Get the estimate frame that is playing at this moment
116 int64_t getEstimatedFrame() const { return int64_t(estimated_frame); }
117
118 /// Set Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
119 void setSpeed(int new_speed) { speed = new_speed; }
120 /// Get Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
121 int getSpeed() const { return speed; }
122
123 /// Set Reader
124 void Reader(ReaderBase *audio_reader) { reader = audio_reader; }
125 /// Get Reader
126 ReaderBase* Reader() const { return reader; }
127
128 /// Seek to a specific frame
129 void Seek(int64_t new_position) { frame_number = new_position; estimated_frame = new_position; }
130
131 };
132
133}
134
135#endif
#define int64
Definition: Clip.h:35
Header file for ReaderBase class.
This class is used to expose any ReaderBase derived class as an AudioSource in JUCE.
juce::int64 getNextReadPosition() const
Get the next read position of this source.
void Seek(int64_t new_position)
Seek to a specific frame.
AudioReaderSource(ReaderBase *audio_reader, int64_t starting_frame_number, int buffer_size)
Constructor that reads samples from a reader.
int getSpeed() const
Get Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster,...
int64_t getEstimatedFrame() const
Get the estimate frame that is playing at this moment.
void setNextReadPosition(juce::int64 newPosition)
Set the next read position of this source.
void releaseResources()
Release all resources.
void Reader(ReaderBase *audio_reader)
Set Reader.
const ReaderInfo & getReaderInfo() const
bool isLooping() const
Determines if this audio source should repeat when it reaches the end.
juce::int64 getTotalLength() const
Get the total length (in samples) of this audio source.
void setSpeed(int new_speed)
Set Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster,...
void setLooping(bool shouldLoop)
Set if this audio source should repeat when it reaches the end.
void prepareToPlay(int, double)
Prepare to play this audio source.
ReaderBase * Reader() const
Get Reader.
void setBuffer(juce::AudioSampleBuffer *audio_buffer)
Update the internal buffer used by this source.
void getNextAudioBlock(const juce::AudioSourceChannelInfo &info)
Get the next block of audio samples.
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:98
openshot::ReaderInfo info
Information about the current media file.
Definition: ReaderBase.h:111
This namespace is the default namespace for all code in the openshot library.
Definition: Compressor.h:47
This struct contains info about a media file, such as height, width, frames per second,...
Definition: ReaderBase.h:61