Discrete Fourier Transforms

No overview available.

Topics

Objects that Simplify Discrete Fourier Transforms

class vDSP.DFT

A single- and double-precision discrete Fourier transform.

enum vDSP.DFTTransformType

Discrete Fourier transform types.

Discrete Fourier Transforms

The functions in the Discrete Fourier Transforms (DFT) family calculate a discrete Fourier transform of a specified length on a vector.

func vDSP_DFT_zop_CreateSetup(vDSP_DFT_Setup?, vDSP_Length, vDSP_DFT_Direction) -> vDSP_DFT_Setup?

Creates a data structure for use with vDSP_DFT_Execute(_:_:_:_:_:) or vDSP_DCT_Execute(_:_:_:) to perform a complex-to-complex discrete Fourier transform, forward or inverse.

func vDSP_DFT_zop_CreateSetupD(vDSP_DFT_SetupD?, vDSP_Length, vDSP_DFT_Direction) -> vDSP_DFT_SetupD?

Creates a data structure for use with vDSP_DFT_ExecuteD(_:_:_:_:_:) to perform a double-precision, complex-to-complex discrete Fourier transform, forward or inverse.

func vDSP_DFT_zrop_CreateSetup(vDSP_DFT_Setup?, vDSP_Length, vDSP_DFT_Direction) -> vDSP_DFT_Setup?

Creates a data structure for use with vDSP_DFT_Execute(_:_:_:_:_:) to perform a single-precision discrete Fourier transform, forward (real to complex) or inverse (complex to real).

func vDSP_DFT_zrop_CreateSetupD(vDSP_DFT_SetupD?, vDSP_Length, vDSP_DFT_Direction) -> vDSP_DFT_SetupD?

Creates a data structure for use with vDSP_DFT_ExecuteD(_:_:_:_:_:) to perform a double-precision discrete Fourier transform, forward (real to complex) or inverse (complex to real).

func vDSP_DFT_DestroySetup(vDSP_DFT_Setup?)

Releases a single-precision setup object.

func vDSP_DFT_DestroySetupD(vDSP_DFT_SetupD?)

Releases a double-precision setup object.

Data Types

typealias vDSP_DFT_Setup

An opaque type that contains setup information for a given DFT transform.

Constants

enum vDSP_DFT_Direction

Specifies whether to perform a forward or inverse DFT.

See Also

Fourier and Cosine Transforms

Finding the Component Frequencies in a Composite Sine Wave

Use 1D fast Fourier transform to compute the frequency components of a signal.

Using Windowing with Discrete Fourier Transforms

Multiply signal data by window sequence values to reduce spectral leakage.

Signal Extraction from Noise

Use Accelerate’s discrete cosine transform to remove noise from a signal.

Halftone Descreening with 2D Fast Fourier Transform

Reduce or remove periodic artifacts from images.