openal-soft/common/alcomplex.h
2018-05-24 00:16:50 -07:00

72 lines
1.7 KiB
C

#ifndef ALCOMPLEX_H
#define ALCOMPLEX_H
#include "AL/al.h"
#ifdef __cplusplus
extern "C" {
#endif
typedef struct ALcomplex {
ALdouble Real;
ALdouble Imag;
} ALcomplex;
/** Addition of two complex numbers. */
inline ALcomplex complex_add(ALcomplex a, ALcomplex b)
{
ALcomplex result;
result.Real = a.Real + b.Real;
result.Imag = a.Imag + b.Imag;
return result;
}
/** Subtraction of two complex numbers. */
inline ALcomplex complex_sub(ALcomplex a, ALcomplex b)
{
ALcomplex result;
result.Real = a.Real - b.Real;
result.Imag = a.Imag - b.Imag;
return result;
}
/** Multiplication of two complex numbers. */
inline ALcomplex complex_mult(ALcomplex a, ALcomplex b)
{
ALcomplex result;
result.Real = a.Real*b.Real - a.Imag*b.Imag;
result.Imag = a.Imag*b.Real + a.Real*b.Imag;
return result;
}
/**
* Iterative implementation of 2-radix FFT (In-place algorithm). Sign = -1 is
* FFT and 1 is iFFT (inverse). Fills FFTBuffer[0...FFTSize-1] with the
* Discrete Fourier Transform (DFT) of the time domain data stored in
* FFTBuffer[0...FFTSize-1]. FFTBuffer is an array of complex numbers, FFTSize
* MUST BE power of two.
*/
void complex_fft(ALcomplex *FFTBuffer, ALsizei FFTSize, ALdouble Sign);
/**
* Calculate the complex helical sequence (discrete-time analytical signal) of
* the given input using the discrete Hilbert transform (In-place algorithm).
* Fills Buffer[0...size-1] with the discrete-time analytical signal stored in
* Buffer[0...size-1]. Buffer is an array of complex numbers, size MUST BE
* power of two.
*/
void complex_hilbert(ALcomplex *Buffer, ALsizei size);
#ifdef __cplusplus
} // extern "C"
#endif
#endif /* ALCOMPLEX_H */