Files
libopenshot/src/AudioReaderSource.h

104 lines
3.7 KiB
C++

/**
* @file
* @brief Header file for AudioReaderSource class
* @author Jonathan Thomas <jonathan@openshot.org>
*
* @ref License
*/
// Copyright (c) 2008-2019 OpenShot Studios, LLC
//
// SPDX-License-Identifier: LGPL-3.0-or-later
#ifndef OPENSHOT_AUDIOREADERSOURCE_H
#define OPENSHOT_AUDIOREADERSOURCE_H
#include "ReaderBase.h"
#include "Qt/VideoCacheThread.h"
#include <AppConfig.h>
#include <juce_audio_basics/juce_audio_basics.h>
/// This namespace is the default namespace for all code in the openshot library
namespace openshot
{
class Frame;
/**
* @brief This class is used to expose any ReaderBase derived class as an AudioSource in JUCE.
*
* This allows any reader to play audio through JUCE (our audio framework).
*/
class AudioReaderSource : public juce::PositionableAudioSource
{
private:
int stream_position; /// The absolute stream position (required by PositionableAudioSource, but ignored)
int frame_position; /// The frame position (current frame for audio playback)
int speed; /// The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
ReaderBase *reader; /// The reader to pull samples from
std::shared_ptr<Frame> frame; /// The current frame object that is being read
int64_t sample_position; /// The position of the current frame's audio buffer
openshot::VideoCacheThread *videoCache; /// The cache thread (for pre-roll checking)
public:
/// @brief Constructor that reads samples from a reader
/// @param audio_reader This reader provides constant samples from a ReaderBase derived class
/// @param starting_frame_number This is the frame number to start reading samples from the reader.
AudioReaderSource(ReaderBase *audio_reader, int64_t starting_frame_number);
/// Destructor
~AudioReaderSource();
/// @brief Get the next block of audio samples
/// @param info This struct informs us of which samples are needed next.
void getNextAudioBlock (const juce::AudioSourceChannelInfo& info);
/// Prepare to play this audio source
void prepareToPlay(int, double);
/// Release all resources
void releaseResources();
/// @brief Set the next read position of this source
/// @param newPosition The sample # to start reading from
void setNextReadPosition (juce::int64 newPosition) { stream_position = newPosition; };
/// Get the next read position of this source
juce::int64 getNextReadPosition() const { return stream_position; };
/// Get the total length (in samples) of this audio source
juce::int64 getTotalLength() const;
/// Looping is not support in OpenShot audio playback (this is always false)
bool isLooping() const { return false; };
/// @brief This method is ignored (we do not support looping audio playback)
/// @param shouldLoop Determines if the audio source should repeat when it reaches the end
void setLooping (bool shouldLoop) { };
/// Return the current frame object
std::shared_ptr<Frame> getFrame() const { return frame; }
/// Set Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
void setSpeed(int new_speed) { speed = new_speed; }
/// Get Speed (The speed and direction to playback a reader (1=normal, 2=fast, 3=faster, -1=rewind, etc...)
int getSpeed() const { return speed; }
/// Set playback video cache thread (for pre-roll reference)
void setVideoCache(openshot::VideoCacheThread *newCache) { videoCache = newCache; }
/// Set Reader
void Reader(ReaderBase *audio_reader) { reader = audio_reader; }
/// Get Reader
ReaderBase* Reader() const { return reader; }
/// Seek to a specific frame
void Seek(int64_t new_position) { frame_position = new_position; sample_position=0; }
};
}
#endif