ShortFastFourierTransform Class Reference

This class performs direct and inverse ShortFast Fourier Transform. More...

Public Member Functions
void	fft (ShortArray input, ComplexShortArray output)
	Perform the direct FFT. More...
size_t	getSize ()
	Get the size of the FFT. More...
void	ifft (ComplexShortArray input, ShortArray output)
	Perform the inverse FFT. More...
void	init (int aSize)
	Initialize the instance. More...
	ShortFastFourierTransform ()
	Default constructor. More...
	ShortFastFourierTransform (int aSize)
	Construct and initialize the instance. More...
	~ShortFastFourierTransform ()

Detailed Description

This class performs direct and inverse ShortFast Fourier Transform.

Note that on ARM, this links in static coefficients for all supported FFT sizes!

Definition at line 17 of file ShortFastFourierTransform.h.

Constructor & Destructor Documentation

ShortFastFourierTransform() [1/2]

ShortFastFourierTransform::ShortFastFourierTransform

(

)

Default constructor.

Does not initialize the instance.

Remarks

You need to call init(int size) before calling any other method

Definition at line 41 of file ShortFastFourierTransform.cpp.

ShortFastFourierTransform() [2/2]

ShortFastFourierTransform::ShortFastFourierTransform

(

int

aSize

)

Construct and initialize the instance.

Parameters

[in]

aSize

The size of the FFT

Remarks

Only sizes of 32, 64, 128, 256, 512, 1024, 2048, 4096 are supported, due to limitations of the CMSIS library.

Note

When built for ARM Cortex-M processor series, this method uses the optimized CMSIS library

Definition at line 43 of file ShortFastFourierTransform.cpp.

References init().

~ShortFastFourierTransform()

ShortFastFourierTransform::~ShortFastFourierTransform

(

)

Definition at line 47 of file ShortFastFourierTransform.cpp.

References ASSERT, and ComplexShortArray::destroy().

Member Function Documentation

fft()

void ShortFastFourierTransform::fft	(	ShortArray	input,
		ComplexShortArray	output
	)

Perform the direct FFT.

Parameters

[in]	input	The real-valued input array
[out]	output	The complex-valued output array

Remarks

Calling this method will mess up the content of the input array.

Note

When built for ARM Cortex-M processor series, this method uses the optimized CMSIS library

Definition at line 59 of file ShortFastFourierTransform.cpp.

References ASSERT, SimpleArray< T >::getData(), getSize(), SimpleArray< T >::getSize(), ComplexShortArray::im(), and ComplexShortArray::re().

getSize()

size_t ShortFastFourierTransform::getSize

(

)

Get the size of the FFT.

Returns

The size of the FFT

Definition at line 79 of file ShortFastFourierTransform.cpp.

References SimpleArray< T >::getSize().

Referenced by fft(), ifft(), and init().

ifft()

void ShortFastFourierTransform::ifft	(	ComplexShortArray	input,
		ShortArray	output
	)

Perform the inverse FFT.

The output is rescaled by 1/fftSize.

Parameters

[in]	input	The complex-valued input array
[out]	output	The real-valued output array

Remarks

Calling this method will mess up the content of the input array.

Note

When built for ARM Cortex-M processor series, this method uses the optimized CMSIS library

Definition at line 69 of file ShortFastFourierTransform.cpp.

References ASSERT, SimpleArray< T >::getData(), getSize(), SimpleArray< T >::getSize(), and ComplexShortArray::re().

init()

void ShortFastFourierTransform::init

(

int

aSize

)

Initialize the instance.

Parameters

aSize

The size of the FFT

Note

When built for ARM Cortex-M processor series, this method uses the optimized CMSIS library

Definition at line 52 of file ShortFastFourierTransform.cpp.

References ASSERT, ComplexShortArray::create(), and getSize().

Referenced by ShortFastFourierTransform().

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

• ShortFastFourierTransform.h
• ShortFastFourierTransform.cpp