/* SigLib FFT and Hanning window test program */

/* Include files */

#include <math.h>
#include <stdlib.h>
#include <siglib.h>


/* Define constants */

#define	FFT_SIZE            512
#define	LOG_FFT_SIZE        9
#define	WINDOW_SIZE         FFT_SIZE

#define SIGNAL_MAGNITUDE    1.0
#define SIGNAL_FREQUENCY    0.019	/* Normalised to 1.0 Hz */

/* Define global variables */

SFLOAT	*pRealData, *pImagData, *pWindowCoeffs, *pResultsData, *pFFTCoeffs;

SFLOAT	SinePhase;

void main (void)
{
    SFIX	SigLibErrorCode;

    pRealData = SUF_VectorArrayAllocate (FFT_SIZE);\       /* Allocate data arrays */
    pImagData = SUF_VectorArrayAllocate (FFT_SIZE);
    pFFTCoeffs = SUF_FftCoefficientAllocate (FFT_SIZE);
    pResultsData = SUF_VectorArrayAllocate (FFT_SIZE);     /* RMS result data array */
    pWindowCoeffs = SUF_VectorArrayAllocate (WINDOW_SIZE); /* Window data array */

    SigLibErrorCode = SIF_Fft (pFFTCoeffs, SIGLIB_NULL_SFIX_PTR, FFT_SIZE); /* Init. FFT */
    if (SigLibErrorCode != SIGLIB_NO_ERROR)
    {
        SUF_Halt;                                          /* Halt on error */
    }

    SinePhase = SIGLIB_ZERO;                               /* Generate signal for FFT input */
    SDA_SignalGenerate (pRealData, SIGLIB_SINE_WAVE, SIGNAL_MAGNITUDE, SIGLIB_FILL,
                         SIGNAL_FREQUENCY, SIGLIB_ZERO, SIGLIB_ZERO, SIGLIB_ZERO, &SinePhase,
                         SIGLIB_NULL_SFLOAT_PTR, FFT_SIZE);

    SIF_Window (pWindowCoeffs, SIGLIB_HANNING, FFT_SIZE);  /* Generate Hanning window table */
    SDA_Window (pRealData, pRealData, pWindowCoeffs, WINDOW_SIZE);  /* Apply window to data */

                                                           /* Perform FFT */
    SDA_Rfft (pRealData, pImagData, pFFTCoeffs, SIGLIB_NULL_SFIX_PTR, FFT_SIZE, LOG_FFT_SIZE);
                                                           /* Scale output for display */
    SDA_Divide (pRealData, pRealData, ((SFLOAT)FFT_SIZE), FFT_SIZE);
    SDA_Divide (pImagData, pImagData, ((SFLOAT)FFT_SIZE), FFT_SIZE);
    SDA_RmsPower (pRealData, pImagData, pResultsData, FFT_SIZE);   /* Calc real power */

    SUF_MemoryFree (pRealData);                            /* Free memory */
    SUF_MemoryFree (pImagData);
    SUF_MemoryFree (pResultsData);
    SUF_MemoryFree (pWindowCoeffs);
}