All the transforms functions currently supported by the DSP library.
This function computes a complex FFT from an input signal. It uses the Radix-4 "Decimate In Time" algorithm and does not perform a calculation "in place" which means that the input buffer has to be different from the output buffer.
Here is the formula of the FFT:
Relative functions:
This function computes a complex inverse FFT from an input signal. It uses the Radix-4 "Decimate In Time" algorithm and does not perform a calculation "in place" which means that the input buffer has to be different from the output buffer.
Here is the formula of the iFFT:
Relative functions:
This function computes a complex FFT from a real input signal. It uses the Radix-4 "Decimate In Time" algorithm and does not perform a calculation "in place" which means that the input buffer has to be different from the output buffer.
Here is the formula of the FFT:
Relative functions:
Functions | |
void | dsp16_trans_complexfft (dsp16_complex_t *vect1, dsp16_complex_t *vect2, int nlog) |
16-bit fixed point version of the complex FFT algorithm. More... | |
void | dsp16_trans_complexifft (dsp16_complex_t *vect1, dsp16_complex_t *vect2, int nlog) |
16-bit fixed point version of the complex iFFT algorithm. More... | |
void | dsp16_trans_realcomplexfft (dsp16_complex_t *vect1, dsp16_t *vect2, int nlog) |
16-bit fixed point version of the real to complex FFT algorithm. More... | |
void | dsp32_trans_realcomplexfft (dsp32_complex_t *vect1, dsp32_t *vect2, int nlog) |
32-bit fixed point version of the real to complex FFT algorithm. More... | |
void dsp16_trans_complexfft | ( | dsp16_complex_t * | vect1, |
dsp16_complex_t * | vect2, | ||
int | nlog | ||
) |
16-bit fixed point version of the complex FFT algorithm.
vect1 | A pointer on a 16-bit complex vector which is the output buffer of this function. |
vect2 | A pointer on a 16-bit complex vector which is the input buffer of this function. |
nlog | It is the base-2-logarithm of the size of the input/output vector. Due to its implementation, this function computes only 4^n-point complex FFT. Therefore, the nlog argument has to be even. |
16-bit fixed point version of the complex FFT algorithm.
References DSP16_N_TWIDDLE_FACTORS, DSP16_QB, dsp16_twiddle_factors, dsp16_twiddle_factors2, dsp16_complex_t::imag, j, dsp16_complex_t::real, and temp.
void dsp16_trans_complexifft | ( | dsp16_complex_t * | vect1, |
dsp16_complex_t * | vect2, | ||
int | nlog | ||
) |
16-bit fixed point version of the complex iFFT algorithm.
vect1 | A pointer on a 16-bit complex vector which is the output buffer of this function. |
vect2 | A pointer on a 16-bit complex vector which is the input buffer of this function. |
nlog | It is the base-2-logarithm of the size of the input/output vector. Due to its implementation, this function computes only 4^n-point complex iFFT. Therefore, the nlog argument has to be even. |
16-bit fixed point version of the complex iFFT algorithm.
References DSP16_N_TWIDDLE_FACTORS, DSP16_QB, dsp16_twiddle_factors, dsp16_twiddle_factors2, dsp16_vect_complex_conj(), dsp16_complex_t::imag, j, dsp16_complex_t::real, and temp.
void dsp16_trans_realcomplexfft | ( | dsp16_complex_t * | vect1, |
dsp16_t * | vect2, | ||
int | nlog | ||
) |
16-bit fixed point version of the real to complex FFT algorithm.
vect1 | A pointer on a 16-bit complex vector which is the output buffer of this function. |
vect2 | A pointer on a 16-bit real vector which is the input buffer of this function. |
nlog | It is the base-2-logarithm of the size of the input/output vector. Due to its implementation, this function computes only 4^n-point complex FFT. Therefore, the nlog argument has to be even. |
16-bit fixed point version of the real to complex FFT algorithm.
References DSP16_N_TWIDDLE_FACTORS, DSP16_QB, dsp16_twiddle_factors, dsp16_twiddle_factors2, dsp16_complex_t::imag, j, dsp16_complex_t::real, and temp.
Referenced by mfcc_fft_512pts().
void dsp32_trans_realcomplexfft | ( | dsp32_complex_t * | vect1, |
dsp32_t * | vect2, | ||
int | nlog | ||
) |
32-bit fixed point version of the real to complex FFT algorithm.
vect1 | A pointer on a 32-bit complex vector which is the output buffer of this function. |
vect2 | A pointer on a 32-bit real vector which is the input buffer of this function. |
nlog | It is the base-2-logarithm of the size of the input/output vector. Due to its implementation, this function computes only 4^n-point complex FFT. Therefore, the nlog argument has to be even. |
References DSP32_N_TWIDDLE_FACTORS, DSP32_QB, dsp32_twiddle_factors, dsp32_twiddle_factors2, dsp32_complex_t::imag, j, dsp32_complex_t::real, and temp.