Home   Information   Classes   Download   Usage   Mail List   Requirements   Links   FAQ   Tutorial


Public Member Functions | List of all members
stk::FileLoop Class Reference

STK file looping / oscillator class. More...

#include <FileLoop.h>

Inheritance diagram for stk::FileLoop:
stk::FileWvIn stk::WvIn stk::Stk

Public Member Functions

 FileLoop (unsigned long chunkThreshold=1000000, unsigned long chunkSize=1024)
 Default constructor.
 
 FileLoop (std::string fileName, bool raw=false, bool doNormalize=true, unsigned long chunkThreshold=1000000, unsigned long chunkSize=1024)
 Class constructor that opens a specified file.
 
 ~FileLoop (void)
 Class destructor.
 
void openFile (std::string fileName, bool raw=false, bool doNormalize=true)
 Open the specified file and load its data. More...
 
void closeFile (void)
 Close a file if one is open.
 
void reset (void)
 Clear outputs and reset time (file) pointer to zero.
 
unsigned int channelsOut (void) const
 Return the number of audio channels in the data or stream.
 
void normalize (void)
 Normalize data to a maximum of +-1.0. More...
 
void normalize (StkFloat peak)
 Normalize data to a maximum of +-peak. More...
 
unsigned long getSize (void) const
 Return the file size in sample frames.
 
StkFloat getFileRate (void) const
 Return the input file sample rate in Hz (not the data read rate). More...
 
void setRate (StkFloat rate)
 Set the data read rate in samples. The rate can be negative. More...
 
void setFrequency (StkFloat frequency)
 Set the data interpolation rate based on a looping frequency. More...
 
void addTime (StkFloat time)
 Increment the read pointer by time samples, modulo file size.
 
void addPhase (StkFloat angle)
 Increment current read pointer by angle, relative to a looping frequency. More...
 
void addPhaseOffset (StkFloat angle)
 Add a phase offset to the current read pointer. More...
 
StkFloat lastOut (unsigned int channel=0)
 Return the specified channel value of the last computed frame. More...
 
StkFloat tick (unsigned int channel=0)
 Compute a sample frame and return the specified channel value. More...
 
StkFramestick (StkFrames &frames)
 Fill the StkFrames argument with computed frames and return the same reference. More...
 

Additional Inherited Members

- Protected Member Functions inherited from stk::FileWvIn
 FileWvIn (unsigned long chunkThreshold=1000000, unsigned long chunkSize=1024)
 Default constructor.
 
 FileWvIn (std::string fileName, bool raw=false, bool doNormalize=true, unsigned long chunkThreshold=1000000, unsigned long chunkSize=1024)
 Overloaded constructor for file input. More...
 
 ~FileWvIn (void)
 Class destructor.
 
bool isOpen (void)
 Query whether a file is open.
 
bool isFinished (void) const
 Query whether reading is complete.
 
void setInterpolate (bool doInterpolate)
 Turn linear interpolation on/off. More...
 
StkFloat lastOut (unsigned int channel=0)
 Return the specified channel value of the last computed frame. More...
 
- Static Protected Member Functions inherited from stk::Stk
static StkFloat sampleRate (void)
 Static method that returns the current STK sample rate.
 
static void setSampleRate (StkFloat rate)
 Static method that sets the STK sample rate. More...
 
static std::string rawwavePath (void)
 Static method that returns the current rawwave path.
 
static void setRawwavePath (std::string path)
 Static method that sets the STK rawwave path.
 
static void swap16 (unsigned char *ptr)
 Static method that byte-swaps a 16-bit data type.
 
static void swap32 (unsigned char *ptr)
 Static method that byte-swaps a 32-bit data type.
 
static void swap64 (unsigned char *ptr)
 Static method that byte-swaps a 64-bit data type.
 
static void sleep (unsigned long milliseconds)
 Static cross-platform method to sleep for a number of milliseconds.
 
static bool inRange (StkFloat value, StkFloat min, StkFloat max)
 Static method to check whether a value is within a specified range.
 
static void handleError (const char *message, StkError::Type type)
 Static function for error reporting and handling using c-strings.
 
static void handleError (std::string message, StkError::Type type)
 Static function for error reporting and handling using c++ strings.
 
static void showWarnings (bool status)
 Toggle display of WARNING and STATUS messages.
 
static void printErrors (bool status)
 Toggle display of error messages before throwing exceptions.
 
- Static Protected Attributes inherited from stk::Stk
static const StkFormat STK_SINT8
 
static const StkFormat STK_SINT16
 
static const StkFormat STK_SINT24
 
static const StkFormat STK_SINT32
 
static const StkFormat STK_FLOAT32
 
static const StkFormat STK_FLOAT64
 

Detailed Description

STK file looping / oscillator class.

This class provides audio file looping functionality. Any audio file that can be loaded by FileRead can be looped using this class.

FileLoop supports multi-channel data. It is important to distinguish the tick() method that computes a single frame (and returns only the specified sample of a multi-channel frame) from the overloaded one that takes an StkFrames object for multi-channel and/or multi-frame data.

by Perry R. Cook and Gary P. Scavone, 1995–2014.

Member Function Documentation

void stk::FileLoop::openFile ( std::string  fileName,
bool  raw = false,
bool  doNormalize = true 
)
virtual

Open the specified file and load its data.

Data from a previously opened file will be overwritten by this function. An StkError will be thrown if the file is not found, its format is unknown, or a read error occurs. If the file data is to be loaded incrementally from disk and normalization is specified, a scaling will be applied with respect to fixed-point limits. If the data format is floating-point, no scaling is performed.

Reimplemented from stk::FileWvIn.

void stk::FileLoop::normalize ( void  )
inlinevirtual

Normalize data to a maximum of +-1.0.

This function has no effect when data is incrementally loaded from disk.

Reimplemented from stk::FileWvIn.

65 { FileWvIn::normalize( 1.0 ); };
void stk::FileLoop::normalize ( StkFloat  peak)
inlinevirtual

Normalize data to a maximum of +-peak.

This function has no effect when data is incrementally loaded from disk.

Reimplemented from stk::FileWvIn.

72 { FileWvIn::normalize( peak ); };
StkFloat stk::FileLoop::getFileRate ( void  ) const
inlinevirtual

Return the input file sample rate in Hz (not the data read rate).

WAV, SND, and AIF formatted files specify a sample rate in their headers. STK RAW files have a sample rate of 22050 Hz by definition. MAT-files are assumed to have a rate of 44100 Hz.

Reimplemented from stk::FileWvIn.

83 { return data_.dataRate(); };
void stk::FileLoop::setRate ( StkFloat  rate)
virtual

Set the data read rate in samples. The rate can be negative.

If the rate value is negative, the data is read in reverse order.

Reimplemented from stk::FileWvIn.

void stk::FileLoop::setFrequency ( StkFloat  frequency)
inline

Set the data interpolation rate based on a looping frequency.

This function determines the interpolation rate based on the file size and the current Stk::sampleRate. The frequency value corresponds to file cycles per second. The frequency can be negative, in which case the loop is read in reverse order.

98 { this->setRate( file_.fileSize() * frequency / Stk::sampleRate() ); };
void stk::FileLoop::addPhase ( StkFloat  angle)

Increment current read pointer by angle, relative to a looping frequency.

This function increments the read pointer based on the file size and the current Stk::sampleRate. The anAngle value is a multiple of file size.

void stk::FileLoop::addPhaseOffset ( StkFloat  angle)

Add a phase offset to the current read pointer.

This function determines a time offset based on the file size and the current Stk::sampleRate. The angle value is a multiple of file size.

StkFloat stk::FileLoop::lastOut ( unsigned int  channel = 0)
inline

Return the specified channel value of the last computed frame.

For multi-channel files, use the lastFrame() function to get all values from the last computed frame. If no file data is loaded, the returned value is 0.0. The channel argument must be less than the number of channels in the file data (the first channel is specified by 0). However, range checking is only performed if STK_DEBUG is defined during compilation, in which case an out-of-range value will trigger an StkError exception.

129 { return FileWvIn::lastOut( channel ); };
StkFloat stk::FileLoop::tick ( unsigned int  channel = 0)
virtual

Compute a sample frame and return the specified channel value.

For multi-channel files, use the lastFrame() function to get all values from the computed frame. If no file data is loaded, the returned value is 0.0. The channel argument must be less than the number of channels in the file data (the first channel is specified by 0). However, range checking is only performed if STK_DEBUG is defined during compilation, in which case an out-of-range value will trigger an StkError exception.

Reimplemented from stk::FileWvIn.

StkFrames& stk::FileLoop::tick ( StkFrames frames)
virtual

Fill the StkFrames argument with computed frames and return the same reference.

The number of channels in the StkFrames argument should equal the number of channels in the file data. However, this is only checked if STK_DEBUG is defined during compilation, in which case an incompatibility will trigger an StkError exception. If no file data is loaded, the function does nothing (a warning will be issued if STK_DEBUG is defined during compilation and Stk::showWarnings() has been set to true).

Reimplemented from stk::FileWvIn.


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

The Synthesis ToolKit in C++ (STK)
©1995--2014 Perry R. Cook and Gary P. Scavone. All Rights Reserved.