NE10_fft_common_varibles.h

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/*
 * NE10 Library : dsp/NE10_fft_common_varibles.h
 */

#include "NE10_types.h"

#ifndef NE10_FFT_COMMON_VARIBLES_H
#define NE10_FFT_COMMON_VARIBLES_H

// common varibles

/* Twiddles used in Radix-8 FFT */
const static ne10_float32_t TW_81_F32  =  0.70710678; // sqrt (2) / 2
const static ne10_float32_t TW_81N_F32 = -0.70710678; // - TW_81_F32

/* Twiddles used in Radix-5 FFT */
const static ne10_fft_cpx_float32_t TW_5A_F32 =
        {
             0.309016994374947, //   cos (2 * pi / 5)
            -0.951056516295154  // - sin (2 * pi / 5)
        };
const static ne10_fft_cpx_int32_t TW_5A_S32 =
        {
              663608942, // round (TW_5A_F32.r * 2^31)
            -2042378317  // round (TW_5A_F32.i * 2^31)
        };

const static ne10_fft_cpx_float32_t TW_5B_F32 =
        {
            -0.809016994374947, //   cos (4 * pi / 5)
            -0.587785252292473  // - sin (4 * pi / 5)
        };
const static ne10_fft_cpx_int32_t TW_5B_S32 =
        {
            -1737350766, // round (TW_5B_F32.r * 2^31)
            -1262259218  // round (TW_5B_F32.i * 2^31)
        };

/* Twiddles used in Radix-3 FFT */
const static ne10_float32_t TW_3I_F32  =   0.866025403784439; // sqrt (3) / 2
const static ne10_float32_t TW_3IN_F32 = - 0.866025403784439; // - TW_3IN_F32
const static ne10_int32_t TW_3I_S32 = 1859775393; // round (TW_3I_F32 * 2^31)
const static ne10_int32_t TW_3IN_S32 = -1859775393; // round (TW_3IN_F32 * 2^31)

#endif // NE10_FFT_COMMON_VARIBLES_H