JUCE  v5.4.1-191-g0ab5e696f
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juce::CoreAudioFormat Class Reference

OSX and iOS only - This uses the AudioToolbox framework to read any audio format that the system has a codec for. More...

#include <juce_CoreAudioFormat.h>

Inheritance diagram for juce::CoreAudioFormat:
Collaboration diagram for juce::CoreAudioFormat:

Public Member Functions

 CoreAudioFormat ()
 Creates a format object. More...
 
 ~CoreAudioFormat () override
 Destructor. More...
 
bool canDoMono () override
 Returns true if the format can do 1-channel audio. More...
 
bool canDoStereo () override
 Returns true if the format can do 2-channel audio. More...
 
virtual bool canHandleFile (const File &fileToTest)
 Returns true if this the given file can be read by this format. More...
 
virtual MemoryMappedAudioFormatReadercreateMemoryMappedReader (const File &file)
 Attempts to create a MemoryMappedAudioFormatReader, if possible for this format. More...
 
virtual MemoryMappedAudioFormatReadercreateMemoryMappedReader (FileInputStream *fin)
 
AudioFormatReadercreateReaderFor (InputStream *, bool deleteStreamIfOpeningFails) override
 Tries to create an object that can read from a stream containing audio data in this format. More...
 
AudioFormatWritercreateWriterFor (OutputStream *, double sampleRateToUse, unsigned int numberOfChannels, int bitsPerSample, const StringPairArray &metadataValues, int qualityOptionIndex) override
 Tries to create an object that can write to a stream with this audio format. More...
 
virtual AudioFormatWritercreateWriterFor (OutputStream *streamToWriteTo, double sampleRateToUse, const AudioChannelSet &channelLayout, int bitsPerSample, const StringPairArray &metadataValues, int qualityOptionIndex)
 Tries to create an object that can write to a stream with this audio format. More...
 
virtual StringArray getFileExtensions () const
 Returns all the file extensions that might apply to a file of this format. More...
 
const StringgetFormatName () const
 Returns the name of this format. More...
 
Array< intgetPossibleBitDepths () override
 Returns a set of bit depths that the format can read and write. More...
 
Array< intgetPossibleSampleRates () override
 Returns a set of sample rates that the format can read and write. More...
 
virtual StringArray getQualityOptions ()
 Returns a list of different qualities that can be used when writing. More...
 
virtual bool isChannelLayoutSupported (const AudioChannelSet &channelSet)
 Returns true if the channel layout is supported by this format. More...
 
virtual bool isCompressed ()
 Returns true if the format uses compressed data. More...
 

Static Public Attributes

static const char *const keySig
 Metadata property name used when reading a caf file time signature information. More...
 
static const char *const midiDataBase64
 Metadata property name used when reading a caf file with a MIDI chunk. More...
 
static const char *const tempo
 Metadata property name used when reading a caf file with tempo information. More...
 
static const char *const timeSig
 Metadata property name used when reading a caf file time signature information. More...
 

Detailed Description

OSX and iOS only - This uses the AudioToolbox framework to read any audio format that the system has a codec for.

This should be able to understand formats such as mp3, m4a, etc.

See also
AudioFormat

{Audio}

Constructor & Destructor Documentation

◆ CoreAudioFormat()

juce::CoreAudioFormat::CoreAudioFormat ( )

Creates a format object.

◆ ~CoreAudioFormat()

juce::CoreAudioFormat::~CoreAudioFormat ( )
override

Destructor.

Member Function Documentation

◆ canDoMono()

bool juce::CoreAudioFormat::canDoMono ( )
overridevirtual

Returns true if the format can do 1-channel audio.

Implements juce::AudioFormat.

◆ canDoStereo()

bool juce::CoreAudioFormat::canDoStereo ( )
overridevirtual

Returns true if the format can do 2-channel audio.

Implements juce::AudioFormat.

◆ canHandleFile()

virtual bool juce::AudioFormat::canHandleFile ( const File fileToTest)
virtualinherited

Returns true if this the given file can be read by this format.

Subclasses shouldn't do too much work here, just check the extension or file type. The base class implementation just checks the file's extension against one of the ones that was registered in the constructor.

Reimplemented in juce::AiffAudioFormat, and juce::LAMEEncoderAudioFormat.

◆ createMemoryMappedReader() [1/2]

virtual MemoryMappedAudioFormatReader* juce::AudioFormat::createMemoryMappedReader ( const File file)
virtualinherited

Attempts to create a MemoryMappedAudioFormatReader, if possible for this format.

If the format does not support this, the method will return nullptr;

Reimplemented in juce::WavAudioFormat, and juce::AiffAudioFormat.

◆ createMemoryMappedReader() [2/2]

virtual MemoryMappedAudioFormatReader* juce::AudioFormat::createMemoryMappedReader ( FileInputStream fin)
virtualinherited

◆ createReaderFor()

AudioFormatReader* juce::CoreAudioFormat::createReaderFor ( InputStream sourceStream,
bool  deleteStreamIfOpeningFails 
)
overridevirtual

Tries to create an object that can read from a stream containing audio data in this format.

The reader object that is returned can be used to read from the stream, and should then be deleted by the caller.

Parameters
sourceStreamthe stream to read from - the AudioFormatReader object that is returned will delete this stream when it no longer needs it.
deleteStreamIfOpeningFailsif no reader can be created, this determines whether this method should delete the stream object that was passed-in. (If a valid reader is returned, it will always be in charge of deleting the stream, so this parameter is ignored)
See also
AudioFormatReader

Implements juce::AudioFormat.

◆ createWriterFor() [1/2]

AudioFormatWriter* juce::CoreAudioFormat::createWriterFor ( OutputStream streamToWriteTo,
double  sampleRateToUse,
unsigned int  numberOfChannels,
int  bitsPerSample,
const StringPairArray metadataValues,
int  qualityOptionIndex 
)
overridevirtual

Tries to create an object that can write to a stream with this audio format.

The writer object that is returned can be used to write to the stream, and should then be deleted by the caller.

If the stream can't be created for some reason (e.g. the parameters passed in here aren't suitable), this will return nullptr.

Parameters
streamToWriteTothe stream that the data will go to - this will be deleted by the AudioFormatWriter object when it's no longer needed. If no AudioFormatWriter can be created by this method, the stream will NOT be deleted, so that the caller can re-use it to try to open a different format, etc
sampleRateToUsethe sample rate for the file, which must be one of the ones returned by getPossibleSampleRates()
numberOfChannelsthe number of channels - this must be either 1 or 2, and the choice will depend on the results of canDoMono() and canDoStereo()
bitsPerSamplethe bits per sample to use - this must be one of the values returned by getPossibleBitDepths()
metadataValuesa set of metadata values that the writer should try to write to the stream. Exactly what these are depends on the format, and the subclass doesn't actually have to do anything with them if it doesn't want to. Have a look at the specific format implementation classes to see possible values that can be used
qualityOptionIndexthe index of one of compression qualities returned by the getQualityOptions() method. If there aren't any quality options for this format, just pass 0 in this parameter, as it'll be ignored
See also
AudioFormatWriter

Implements juce::AudioFormat.

◆ createWriterFor() [2/2]

virtual AudioFormatWriter* juce::AudioFormat::createWriterFor ( OutputStream streamToWriteTo,
double  sampleRateToUse,
const AudioChannelSet channelLayout,
int  bitsPerSample,
const StringPairArray metadataValues,
int  qualityOptionIndex 
)
virtualinherited

Tries to create an object that can write to a stream with this audio format.

The writer object that is returned can be used to write to the stream, and should then be deleted by the caller.

If the stream can't be created for some reason (e.g. the parameters passed in here aren't suitable), this will return nullptr.

Parameters
streamToWriteTothe stream that the data will go to - this will be deleted by the AudioFormatWriter object when it's no longer needed. If no AudioFormatWriter can be created by this method, the stream will NOT be deleted, so that the caller can re-use it to try to open a different format, etc
sampleRateToUsethe sample rate for the file, which must be one of the ones returned by getPossibleSampleRates()
channelLayoutthe channel layout for the file. Use isChannelLayoutSupported to check if the writer supports this layout.
bitsPerSamplethe bits per sample to use - this must be one of the values returned by getPossibleBitDepths()
metadataValuesa set of metadata values that the writer should try to write to the stream. Exactly what these are depends on the format, and the subclass doesn't actually have to do anything with them if it doesn't want to. Have a look at the specific format implementation classes to see possible values that can be used
qualityOptionIndexthe index of one of compression qualities returned by the getQualityOptions() method. If there aren't any quality options for this format, just pass 0 in this parameter, as it'll be ignored
See also
AudioFormatWriter

Reimplemented in juce::WavAudioFormat.

◆ getFileExtensions()

virtual StringArray juce::AudioFormat::getFileExtensions ( ) const
virtualinherited

Returns all the file extensions that might apply to a file of this format.

The first item will be the one that's preferred when creating a new file. So for a wav file this might just return ".wav"; for an AIFF file it might return two items, ".aif" and ".aiff"

◆ getFormatName()

const String& juce::AudioFormat::getFormatName ( ) const
inherited

Returns the name of this format.

e.g. "WAV file" or "AIFF file"

◆ getPossibleBitDepths()

Array<int> juce::CoreAudioFormat::getPossibleBitDepths ( )
overridevirtual

Returns a set of bit depths that the format can read and write.

Implements juce::AudioFormat.

◆ getPossibleSampleRates()

Array<int> juce::CoreAudioFormat::getPossibleSampleRates ( )
overridevirtual

Returns a set of sample rates that the format can read and write.

Implements juce::AudioFormat.

◆ getQualityOptions()

virtual StringArray juce::AudioFormat::getQualityOptions ( )
virtualinherited

Returns a list of different qualities that can be used when writing.

Non-compressed formats will just return an empty array, but for something like Ogg-Vorbis or MP3, it might return a list of bit-rates, etc.

When calling createWriterFor(), an index from this array is passed in to tell the format which option is required.

Reimplemented in juce::LAMEEncoderAudioFormat, juce::MP3AudioFormat, juce::FlacAudioFormat, and juce::OggVorbisAudioFormat.

◆ isChannelLayoutSupported()

virtual bool juce::AudioFormat::isChannelLayoutSupported ( const AudioChannelSet channelSet)
virtualinherited

Returns true if the channel layout is supported by this format.

Reimplemented in juce::WavAudioFormat.

◆ isCompressed()

virtual bool juce::AudioFormat::isCompressed ( )
virtualinherited

Member Data Documentation

◆ keySig

const char* const juce::CoreAudioFormat::keySig
static

Metadata property name used when reading a caf file time signature information.

◆ midiDataBase64

const char* const juce::CoreAudioFormat::midiDataBase64
static

Metadata property name used when reading a caf file with a MIDI chunk.

◆ tempo

const char* const juce::CoreAudioFormat::tempo
static

Metadata property name used when reading a caf file with tempo information.

◆ timeSig

const char* const juce::CoreAudioFormat::timeSig
static

Metadata property name used when reading a caf file time signature information.


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