OpenShot Library | libopenshot-audio 0.2.0
juce::MemoryMappedAiffReader Class Reference
+ Inheritance diagram for juce::MemoryMappedAiffReader:

Public Member Functions

 MemoryMappedAiffReader (const File &f, const AiffAudioFormatReader &reader)
 
bool readSamples (int **destSamples, int numDestChannels, int startOffsetInDestBuffer, int64 startSampleInFile, int numSamples) override
 Subclasses must implement this method to perform the low-level read operation.
 
void getSample (int64 sample, float *result) const noexcept override
 Returns the samples for all channels at a given sample position.
 
void readMaxLevels (int64 startSampleInFile, int64 numSamples, Range< float > *results, int numChannelsToRead) override
 Finds the highest and lowest sample levels from a section of the audio stream.
 
- Public Member Functions inherited from juce::MemoryMappedAudioFormatReader
const FilegetFile () const noexcept
 Returns the file that is being mapped.
 
bool mapEntireFile ()
 Attempts to map the entire file into memory.
 
virtual bool mapSectionOfFile (Range< int64 > samplesToMap)
 Attempts to map a section of the file into memory.
 
Range< int64 > getMappedSection () const noexcept
 Returns the sample range that's currently memory-mapped and available for reading.
 
void touchSample (int64 sample) const noexcept
 Touches the memory for the given sample, to force it to be loaded into active memory.
 
size_t getNumBytesUsed () const
 Returns the number of bytes currently being mapped.
 
- Public Member Functions inherited from juce::AudioFormatReader
virtual ~AudioFormatReader ()
 Destructor.
 
const StringgetFormatName () const noexcept
 Returns a description of what type of format this is.
 
bool read (float *const *destChannels, int numDestChannels, int64 startSampleInSource, int numSamplesToRead)
 Reads samples from the stream.
 
bool read (int *const *destChannels, int numDestChannels, int64 startSampleInSource, int numSamplesToRead, bool fillLeftoverChannelsWithCopies)
 Reads samples from the stream.
 
void read (AudioBuffer< float > *buffer, int startSampleInDestBuffer, int numSamples, int64 readerStartSample, bool useReaderLeftChan, bool useReaderRightChan)
 Fills a section of an AudioBuffer from this reader.
 
virtual void readMaxLevels (int64 startSample, int64 numSamples, float &lowestLeft, float &highestLeft, float &lowestRight, float &highestRight)
 Finds the highest and lowest sample levels from a section of the audio stream.
 
int64 searchForLevel (int64 startSample, int64 numSamplesToSearch, double magnitudeRangeMinimum, double magnitudeRangeMaximum, int minimumConsecutiveSamples)
 Scans the source looking for a sample whose magnitude is in a specified range.
 
virtual AudioChannelSet getChannelLayout ()
 Get the channel layout of the audio stream.
 

Additional Inherited Members

- Public Attributes inherited from juce::AudioFormatReader
double sampleRate = 0
 The sample-rate of the stream.
 
unsigned int bitsPerSample = 0
 The number of bits per sample, e.g.
 
int64 lengthInSamples = 0
 The total number of samples in the audio stream.
 
unsigned int numChannels = 0
 The total number of channels in the audio stream.
 
bool usesFloatingPointData = false
 Indicates whether the data is floating-point or fixed.
 
StringPairArray metadataValues
 A set of metadata values that the reader has pulled out of the stream.
 
InputStreaminput
 The input stream, for use by subclasses.
 
- Protected Member Functions inherited from juce::MemoryMappedAudioFormatReader
 MemoryMappedAudioFormatReader (const File &file, const AudioFormatReader &details, int64 dataChunkStart, int64 dataChunkLength, int bytesPerFrame)
 Creates an MemoryMappedAudioFormatReader object.
 
int64 sampleToFilePos (int64 sample) const noexcept
 Converts a sample index to a byte position in the file.
 
int64 filePosToSample (int64 filePos) const noexcept
 Converts a byte position in the file to a sample index.
 
const voidsampleToPointer (int64 sample) const noexcept
 Converts a sample index to a pointer to the mapped file memory.
 
template<typename SampleType , typename Endianness >
Range< floatscanMinAndMaxInterleaved (int channel, int64 startSampleInFile, int64 numSamples) const noexcept
 Used by AudioFormatReader subclasses to scan for min/max ranges in interleaved data.
 
- Protected Member Functions inherited from juce::AudioFormatReader
 AudioFormatReader (InputStream *sourceStream, const String &formatName)
 Creates an AudioFormatReader object.
 
- Static Protected Member Functions inherited from juce::AudioFormatReader
static void clearSamplesBeyondAvailableLength (int **destChannels, int numDestChannels, int startOffsetInDestBuffer, int64 startSampleInFile, int &numSamples, int64 fileLengthInSamples)
 Used by AudioFormatReader subclasses to clear any parts of the data blocks that lie beyond the end of their available length.
 
- Protected Attributes inherited from juce::MemoryMappedAudioFormatReader
File file
 
Range< int64 > mappedSection
 
std::unique_ptr< MemoryMappedFilemap
 
int64 dataChunkStart
 
int64 dataLength
 
int bytesPerFrame
 

Detailed Description

Definition at line 807 of file juce_AiffAudioFormat.cpp.

Constructor & Destructor Documentation

◆ MemoryMappedAiffReader()

juce::MemoryMappedAiffReader::MemoryMappedAiffReader ( const File f,
const AiffAudioFormatReader reader 
)
inline

Definition at line 810 of file juce_AiffAudioFormat.cpp.

Member Function Documentation

◆ readSamples()

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

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

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

Parameters
destChannelsthe array of destination buffers to fill. Some of these pointers may be null
numDestChannelsthe 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
startOffsetInDestBufferthe number of samples from the start of the dest data at which to begin writing
startSampleInFilethe number of samples into the source data at which to begin reading. This value is guaranteed to be >= 0.
numSamplesthe number of samples to read

Implements juce::AudioFormatReader.

Definition at line 817 of file juce_AiffAudioFormat.cpp.

References juce::AudioFormatReader::bitsPerSample, juce::AudioFormatReader::clearSamplesBeyondAvailableLength(), juce::Range< ValueType >::contains(), juce::AudioFormatReader::lengthInSamples, juce::AudioFormatReader::numChannels, juce::MemoryMappedAudioFormatReader::sampleToPointer(), and juce::AudioFormatReader::usesFloatingPointData.

◆ getSample()

void juce::MemoryMappedAiffReader::getSample ( int64  sampleIndex,
float result 
) const
inlineoverridevirtualnoexcept

Returns the samples for all channels at a given sample position.

The result array must be large enough to hold a value for each channel that this reader contains.

Implements juce::MemoryMappedAudioFormatReader.

Definition at line 841 of file juce_AiffAudioFormat.cpp.

References juce::AudioFormatReader::bitsPerSample, juce::Range< ValueType >::contains(), juce::AudioFormatReader::numChannels, juce::MemoryMappedAudioFormatReader::sampleToPointer(), and juce::AudioFormatReader::usesFloatingPointData.

◆ readMaxLevels()

void juce::MemoryMappedAiffReader::readMaxLevels ( int64  startSample,
int64  numSamples,
Range< float > *  results,
int  numChannelsToRead 
)
inlineoverridevirtual

Finds the highest and lowest sample levels from a section of the audio stream.

This will read a block of samples from the stream, and measure the highest and lowest sample levels from the channels in that section, returning these as normalised floating-point levels.

Parameters
startSamplethe offset into the audio stream to start reading from. It's ok for this to be beyond the start or end of the stream.
numSampleshow many samples to read
resultsthis array will be filled with Range values for each channel. The array must contain numChannels elements.
numChannelsToReadthe number of channels of data to scan. This must be more than zero, but not more than the total number of channels that the reader contains
See also
read

Reimplemented from juce::AudioFormatReader.

Definition at line 884 of file juce_AiffAudioFormat.cpp.

References juce::AudioFormatReader::bitsPerSample, juce::Range< ValueType >::contains(), juce::AudioFormatReader::lengthInSamples, and juce::AudioFormatReader::usesFloatingPointData.


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