ndps2c

Functions

int main(int argc, char *argv[])

ndps2c [ option ] [ infile ]

  • -l int

    • FFT length \((2 \le L)\)

  • -m int

    • order of cepstrum \((0 \le M \le L/2)\)

  • infile str

    • double-type NDPS

  • stdout

    • double-type cepstrum

Parameters:

  • argc – [in] Number of arguments.

  • argv – [in] Argument vector.

Returns:

0 on success, 1 on failure.

See also

c2ndps

class NegativeDerivativeOfPhaseSpectrumToCepstrum

Convert negative derivative of phase spectrum to cepstral coefficients.

The input is the \((L/2+1)\)-length NDPS:

\[ \begin{array}{cccc} n(0), & n(1), & \ldots, & n(L/2+1), \end{array} \]
and the output is the \(M\)-th order cepstral coefficients:
\[ \begin{array}{cccc} 0, & c(1), & \ldots, & c(M). \end{array} \]
The cepstral coefficients are obtained by using the inverse DFT:
\[ c(m) = \frac{1}{mL} \sum_{k=0}^{L-1} n(k) e^{j2\pi mk / L}. \]

[1] B. Yegnanarayana, “Pole-zero decomposition of speech spectra,” Signal Processing, vol. 3, no. 1, pp. 5-17, 1981.

Public Functions

NegativeDerivativeOfPhaseSpectrumToCepstrum(int fft_length, int num_order)
Parameters:

  • fft_length – [in] Length of NDPS, \(L\).

  • num_order – [in] Order of cepstrum, \(M\).

inline int GetFftLength() const
Returns:

FFT length.

inline int GetNumOrder() const
Returns:

Order of cepstrum.

inline bool IsValid() const
Returns:

True if this object is valid.

bool Run(const std::vector<double> &negative_derivative_of_phase_spectrum, std::vector<double> *cepstrum, NegativeDerivativeOfPhaseSpectrumToCepstrum::Buffer *buffer) const
Parameters:

  • negative_derivative_of_phase_spectrum – [in] \((L/2+1)\)-length NDPS.

  • cepstrum – [out] \(M\)-th order cepstrum.

  • buffer – [out] Buffer.

Returns:

True on success, false on failure.

class Buffer

Buffer for NegativeDerivativeOfPhaseSpectrumToCepstrum class.