juce::BufferingAudioReader Class Reference

#include <juce_BufferingAudioFormatReader.h>

Inheritance diagram for juce::BufferingAudioReader:

Classes
struct	BufferedBlock

Public Member Functions
	BufferingAudioReader (AudioFormatReader *sourceReader, TimeSliceThread &timeSliceThread, int samplesToBuffer)
	~BufferingAudioReader () override
void	setReadTimeout (int timeoutMilliseconds) noexcept
bool	readSamples (int **destSamples, int numDestChannels, int startOffsetInDestBuffer, int64 startSampleInFile, int numSamples) override
Public Member Functions inherited from juce::AudioFormatReader
virtual	~AudioFormatReader ()
const String &	getFormatName () const noexcept
bool	read (float *const *destChannels, int numDestChannels, int64 startSampleInSource, int numSamplesToRead)
bool	read (int *const *destChannels, int numDestChannels, int64 startSampleInSource, int numSamplesToRead, bool fillLeftoverChannelsWithCopies)
bool	read (AudioBuffer< float > *buffer, int startSampleInDestBuffer, int numSamples, int64 readerStartSample, bool useReaderLeftChan, bool useReaderRightChan)
virtual void	readMaxLevels (int64 startSample, int64 numSamples, Range< float > *results, int numChannelsToRead)
virtual void	readMaxLevels (int64 startSample, int64 numSamples, float &lowestLeft, float &highestLeft, float &lowestRight, float &highestRight)
int64	searchForLevel (int64 startSample, int64 numSamplesToSearch, double magnitudeRangeMinimum, double magnitudeRangeMaximum, int minimumConsecutiveSamples)
virtual AudioChannelSet	getChannelLayout ()

Private Member Functions
int	useTimeSlice () override
BufferedBlock *	getBlockContaining (int64 pos) const noexcept
bool	readNextBufferChunk ()
Private Member Functions inherited from juce::TimeSliceClient
virtual	~TimeSliceClient ()=default

Private Attributes
std::unique_ptr< AudioFormatReader >	source
TimeSliceThread &	thread
std::atomic< int64 >	nextReadPosition { 0 }
const int	numBlocks
int	timeoutMs = 0
CriticalSection	lock
OwnedArray< BufferedBlock >	blocks

Static Private Attributes
static constexpr int	samplesPerBlock = 32768

Additional Inherited Members
Public Attributes inherited from juce::AudioFormatReader
double	sampleRate = 0
unsigned int	bitsPerSample = 0
int64	lengthInSamples = 0
unsigned int	numChannels = 0
bool	usesFloatingPointData = false
StringPairArray	metadataValues
InputStream *	input
Protected Member Functions inherited from juce::AudioFormatReader
	AudioFormatReader (InputStream *sourceStream, const String &formatName)
Static Protected Member Functions inherited from juce::AudioFormatReader
static void	clearSamplesBeyondAvailableLength (int **destChannels, int numDestChannels, int startOffsetInDestBuffer, int64 startSampleInFile, int &numSamples, int64 fileLengthInSamples)

Detailed Description

An AudioFormatReader that uses a background thread to pre-read data from another reader.

See also

AudioFormatReader

@tags{Audio}

Constructor & Destructor Documentation

BufferingAudioReader()

juce::BufferingAudioReader::BufferingAudioReader	(	AudioFormatReader *	sourceReader,
		TimeSliceThread &	timeSliceThread,
		int	samplesToBuffer )

Creates a reader.

Parameters

sourceReader	the source reader to wrap. This BufferingAudioReader takes ownership of this object and will delete it later when no longer needed
timeSliceThread	the thread that should be used to do the background reading. Make sure that the thread you supply is running, and won't be deleted while the reader object still exists.
samplesToBuffer	the total number of samples to buffer ahead.

~BufferingAudioReader()

juce::BufferingAudioReader::~BufferingAudioReader ( )

override

Member Function Documentation

getBlockContaining()

BufferingAudioReader::BufferedBlock * juce::BufferingAudioReader::getBlockContaining ( int64 pos ) const

privatenoexcept

readNextBufferChunk()

bool juce::BufferingAudioReader::readNextBufferChunk ( )

private

readSamples()

bool juce::BufferingAudioReader::readSamples ( int ** destChannels, int numDestChannels, int startOffsetInDestBuffer, int64 startSampleInFile, int numSamples )

overridevirtual

Subclasses must implement this method to perform the low-level read operation.

Callers should use read() instead of calling this directly.

Parameters

destChannels	the array of destination buffers to fill. Some of these pointers may be null
numDestChannels	the number of items in the destChannels array. This value is guaranteed not to be greater than the number of channels that this reader object contains
startOffsetInDestBuffer	the number of samples from the start of the dest data at which to begin writing
startSampleInFile	the number of samples into the source data at which to begin reading. This value is guaranteed to be >= 0.
numSamples	the number of samples to read

Implements juce::AudioFormatReader.

setReadTimeout()

void juce::BufferingAudioReader::setReadTimeout ( int timeoutMilliseconds )

noexcept

Sets a number of milliseconds that the reader can block for in its readSamples() method before giving up and returning silence.

A value of less that 0 means "wait forever". The default timeout is 0.

useTimeSlice()

int juce::BufferingAudioReader::useTimeSlice ( )

overrideprivatevirtual

Called back by a TimeSliceThread.

When you register this class with it, a TimeSliceThread will repeatedly call this method.

The implementation of this method should use its time-slice to do something that's quick - never block for longer than absolutely necessary.

Returns

Your method should return the number of milliseconds which it would like to wait before being called again. Returning 0 will make the thread call again as soon as possible (after possibly servicing other busy clients). If you return a value below zero, your client will be removed from the list of clients, and won't be called again. The value you specify isn't a guarantee, and is only used as a hint by the thread - the actual time before the next callback may be more or less than specified. You can force the TimeSliceThread to wake up and poll again immediately by calling its notify() method.

Implements juce::TimeSliceClient.

Member Data Documentation

blocks

OwnedArray<BufferedBlock> juce::BufferingAudioReader::blocks

private

lock

CriticalSection juce::BufferingAudioReader::lock

private

nextReadPosition

std::atomic<int64> juce::BufferingAudioReader::nextReadPosition { 0 }

private

numBlocks

const int juce::BufferingAudioReader::numBlocks

private

samplesPerBlock

int juce::BufferingAudioReader::samplesPerBlock = 32768

staticconstexprprivate

source

std::unique_ptr<AudioFormatReader> juce::BufferingAudioReader::source

private

thread

TimeSliceThread& juce::BufferingAudioReader::thread

private

timeoutMs

int juce::BufferingAudioReader::timeoutMs = 0

private

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The documentation for this class was generated from the following files:

• /home/runner/work/lmms-fork/lmms-fork/plugins/CarlaBase/carla/source/modules/juce_audio_formats/format/juce_BufferingAudioFormatReader.h
• /home/runner/work/lmms-fork/lmms-fork/plugins/CarlaBase/carla/source/modules/juce_audio_formats/format/juce_BufferingAudioFormatReader.cpp