openshot-audio  0.1.4
Classes | Public Member Functions | List of all members
juce::FFT Class Reference

#include <juce_audio_basics.h>

Classes

struct  Complex
 
struct  FFTConfig
 

Public Member Functions

 FFT (int order, bool isInverse)
 
 ~FFT ()
 
void perform (const Complex *input, Complex *output) const noexcept
 
void performRealOnlyForwardTransform (float *inputOutputData) const noexcept
 
void performRealOnlyInverseTransform (float *inputOutputData) const noexcept
 
void performFrequencyOnlyForwardTransform (float *inputOutputData) const noexcept
 
int getSize () const noexcept
 

Detailed Description

A very minimal FFT class.

This is only a simple low-footprint implementation and isn't tuned for speed - it may be useful for simple applications where one of the more complex FFT libraries would be overkill. (But in the future it may end up becoming optimised of course...)

The FFT class itself contains lookup tables, so there's some overhead in creating one, you should create and cache an FFT object for each size/direction of transform that you need, and re-use them to perform the actual operation.

Constructor & Destructor Documentation

◆ FFT()

FFT::FFT ( int  order,
bool  isInverse 
)

Initialises an object for performing either a forward or inverse FFT with the given size. The the number of points the FFT will operate on will be 2 ^ order.

◆ ~FFT()

FFT::~FFT ( )

Destructor.

Member Function Documentation

◆ getSize()

int juce::FFT::getSize ( ) const
inlinenoexcept

Returns the number of data points that this FFT was created to work with.

◆ perform()

void FFT::perform ( const Complex input,
Complex output 
) const
noexcept

Performs an out-of-place FFT, either forward or inverse depending on the mode that was passed to this object's constructor.

The arrays must contain at least getSize() elements.

◆ performFrequencyOnlyForwardTransform()

void FFT::performFrequencyOnlyForwardTransform ( float *  inputOutputData) const
noexcept

Takes an array and simply transforms it to the frequency spectrum. This may be handy for things like frequency displays or analysis.

◆ performRealOnlyForwardTransform()

void FFT::performRealOnlyForwardTransform ( float *  inputOutputData) const
noexcept

Performs an in-place forward transform on a block of real data.

The size of the array passed in must be 2 * getSize(), and the first half should contain your raw input sample data. On return, the array will contain complex frequency + phase data, and can be passed to performRealOnlyInverseTransform() in order to convert it back to reals.

◆ performRealOnlyInverseTransform()

void FFT::performRealOnlyInverseTransform ( float *  inputOutputData) const
noexcept

Performs a reverse operation to data created in performRealOnlyForwardTransform().

The size of the array passed in must be 2 * getSize(), containing complex frequency and phase data. On return, the first half of the array will contain the reconstituted samples.


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