Public Member Functions | List of all members
MP3AudioFormat Class Reference

Software-based MP3 decoding format (doesn't currently provide an encoder). More...

Inheritance diagram for MP3AudioFormat:

Public Member Functions

 MP3AudioFormat ()
 
 ~MP3AudioFormat ()
 
Array< int > getPossibleSampleRates () override
 Returns a set of sample rates that the format can read and write. More...
 
Array< int > getPossibleBitDepths () override
 Returns a set of bit depths that the format can read and write. More...
 
bool canDoStereo () override
 Returns true if the format can do 2-channel audio. More...
 
bool canDoMono () override
 Returns true if the format can do 1-channel audio. More...
 
bool isCompressed () override
 Returns true if the format uses compressed data. More...
 
StringArray getQualityOptions () override
 Returns a list of different qualities that can be used when writing. More...
 
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...
 
- Public Member Functions inherited from AudioFormat
virtual ~AudioFormat ()
 Destructor. More...
 
const StringgetFormatName () const
 Returns the name of this format. More...
 
virtual StringArray getFileExtensions () const
 Returns all the file extensions that might apply to a file of this format. More...
 
virtual bool canHandleFile (const File &fileToTest)
 Returns true if this the given file can be read by this format. More...
 
virtual bool isChannelLayoutSupported (const AudioChannelSet &channelSet)
 Returns true if the channel layout is supported by this format. More...
 
virtual MemoryMappedAudioFormatReadercreateMemoryMappedReader (const File &file)
 Attempts to create a MemoryMappedAudioFormatReader, if possible for this format. More...
 
virtual MemoryMappedAudioFormatReadercreateMemoryMappedReader (FileInputStream *fin)
 
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...
 

Additional Inherited Members

- Protected Member Functions inherited from AudioFormat
 AudioFormat (String formatName, StringArray fileExtensions)
 Creates an AudioFormat object. More...
 
 AudioFormat (StringRef formatName, StringRef fileExtensions)
 Creates an AudioFormat object. More...
 

Detailed Description

Software-based MP3 decoding format (doesn't currently provide an encoder).

IMPORTANT DISCLAIMER: By choosing to enable the JUCE_USE_MP3AUDIOFORMAT flag and to compile the MP3 code into your software, you do so AT YOUR OWN RISK! By doing so, you are agreeing that ROLI Ltd. is in no way responsible for any patent, copyright, or other legal issues that you may suffer as a result.

The code in juce_MP3AudioFormat.cpp is NOT guaranteed to be free from infringements of 3rd-party intellectual property. If you wish to use it, please seek your own independent advice about the legality of doing so. If you are not willing to accept full responsibility for the consequences of using this code, then do not enable the JUCE_USE_MP3AUDIOFORMAT setting.

Constructor & Destructor Documentation

◆ MP3AudioFormat()

MP3AudioFormat::MP3AudioFormat ( )

◆ ~MP3AudioFormat()

MP3AudioFormat::~MP3AudioFormat ( )

Member Function Documentation

◆ getPossibleSampleRates()

Array<int> MP3AudioFormat::getPossibleSampleRates ( )
overridevirtual

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

Implements AudioFormat.

◆ getPossibleBitDepths()

Array<int> MP3AudioFormat::getPossibleBitDepths ( )
overridevirtual

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

Implements AudioFormat.

◆ canDoStereo()

bool MP3AudioFormat::canDoStereo ( )
overridevirtual

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

Implements AudioFormat.

◆ canDoMono()

bool MP3AudioFormat::canDoMono ( )
overridevirtual

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

Implements AudioFormat.

◆ isCompressed()

bool MP3AudioFormat::isCompressed ( )
overridevirtual

Returns true if the format uses compressed data.

Reimplemented from AudioFormat.

◆ getQualityOptions()

StringArray MP3AudioFormat::getQualityOptions ( )
overridevirtual

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 from AudioFormat.

◆ createReaderFor()

AudioFormatReader* MP3AudioFormat::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 AudioFormat.

◆ createWriterFor()

AudioFormatWriter* MP3AudioFormat::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 AudioFormat.


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