Function

vDSP_fftm_zop

Performs the same operation as vDSP_fft_zop, but on multiple signals with a single call.

Declaration

void vDSP_fftm_zop(FFTSetup __Setup, const DSPSplitComplex *__A, vDSP_Stride __IA, vDSP_Stride __IMA, const DSPSplitComplex *__C, vDSP_Stride __IC, vDSP_Stride __IMC, vDSP_Length __Log2N, vDSP_Length __M, FFTDirection __Direction);

Parameters

__Setup

Points to a structure initialized by a prior call to the FFT setup data function, vDSP_create_fftsetup. The value supplied as parameter Log2n of the earlier call to the setup function must equal or exceed the value supplied as parameter Log2N of this transform function.

__A

Complex input vector where multiple signals are concatenated.

__IA

Stride between elements in A. The value of IA should be 1 for best performance.

__IMA

Stride (in elements) between signals in the vector A (which is also the length of each signal, measured in elements).

__C

Complex output vector where multiple signals are concatenated.

__IC

Stride between elements in C. The value of IC should be 1 for best performance.

__IMC

Stride (in elements) between signals in the vector C (which is also the length of each signal, measured in elements).

__Log2N

The base 2 exponent of the number of elements to process in a single input signal. For example, to process 512 elements, specify 9 for parameter Log2N.

__M

The number of input signals.

__Direction

A forward/inverse directional flag, which must specify kFFTDirection_Forward (+1) or kFFTDirection_Inverse (-1).

Discussion

The function performs discrete Fourier transforms on a number of different input signals at once, using a single call. It can be used for efficient processing of small input signals (less than 512 points). It will work for input signals of 4 points or greater. Each of the input signals processed by a given call must have the same length and address stride. The input signals are concatenated into a single output vector, the parameter C.

The function computes out-of-place complex discrete Fourier transforms of the input signals, either from the time domain to the frequency domain (forward) or from the frequency domain to the time domain (inverse).

See also functions vDSP_create_fftsetup, vDSP_destroy_fftsetup, and vDSP Programming Guide.

See Also

1D Fast Fourier Transforms (Out-of-Place Complex)

vDSP_fft_zop

Computes an out-of-place single-precision complex discrete Fourier transform of the input vector, either from the time domain to the frequency domain (forward) or from the frequency domain to the time domain (inverse).

vDSP_fft_zopD

Computes an out-of-place double-precision complex discrete Fourier transform of the input vector, either from the time domain to the frequency domain (forward) or from the frequency domain to the time domain (inverse).

vDSP_fft_zopt

Computes an out-of-place single-precision complex discrete Fourier transform of the input vector, either from the time domain to the frequency domain (forward) or from the frequency domain to the time domain (inverse).

vDSP_fft_zoptD

Computes an out-of-place double-precision complex discrete Fourier transform of the input vector, either from the time domain to the frequency domain (forward) or from the frequency domain to the time domain (inverse).

vDSP_fftm_zopD

Performs the same operation as vDSP_fft_zopD, but on multiple signals with a single call.

vDSP_fftm_zopt

Performs the same operation as vDSP_fft_zopt, but on multiple signals with a single call.

vDSP_fftm_zoptD

Performs the same operation as vDSP_fft_zoptD, but on multiple signals with a single call.

vDSP_fft3_zop

Computes an out-of-place radix-3 complex Fourier transform, either forward or inverse. The number of input and output values processed equals 3 times the power of 2 specified by parameter Log2N; single precision.

Deprecated
vDSP_fft3_zopD

Computes an out-of-place radix-3 complex Fourier transform, either forward or inverse. The number of input and output values processed equals 3 times the power of 2 specified by parameter Log2N; double precision.

Deprecated
vDSP_fft5_zop

Computes an out-of-place radix-5 complex Fourier transform, either forward or inverse. The number of input and output values processed equals 5 times the power of 2 specified by parameter Log2N; single precision.

Deprecated
vDSP_fft5_zopD

Computes an out-of-place radix-5 complex Fourier transform, either forward or inverse. The number of input and output values processed equals 5 times the power of 2 specified by parameter Log2N; double precision.

Deprecated

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