poledf

Functions

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

poledf [ option ] afile [ infile ]

  • -m int

    • order of coefficients \((0 \le M)\)

  • -p int

    • frame period \((1 \le P)\)

  • -i int

    • interpolation period \((0 \le I \le P/2)\)

  • -t

    • transpose filter

  • -k

    • filtering without gain

  • afile str

    • double-type LPC coefficients

  • infile str

    • double-type input sequence

  • stdout

    • double-type output sequence

In the below example, an exciation signal generated from pitch information is passed through the standard form synthesis filter built from LPC coefficients.

excite < data.pitch | poledf data.lpc > data.syn
Parameters:

  • argc – [in] Number of arguments.

  • argv – [in] Argument vector.

Returns:

0 on success, 1 on failure.

See also

acorr lpc

class AllPoleDigitalFilter

Apply all-pole digital filter for speech synthesis to signals.

The transfer function \(H(z)\) of an all-pole filter is

\[ H(z) = \frac{K}{1 + \displaystyle\sum_{m=1}^M a(m)z^{-m}}, \]
where \(M\) is the order of filter and \(K\) is the gain.

Given the \(M\)-th order filter coefficients,

\[ \begin{array}{cccc} K, & a(1), & \ldots, & a(M), \end{array} \]
an output signal is obtained by applying \(H(z)\) to an input signal in time domain.

Public Functions

AllPoleDigitalFilter(int num_filter_order, bool transposition)
Parameters:

  • num_filter_order – [in] Order of filter coefficients, \(M\).

  • transposition – [in] If true, use transposed form filter.

inline int GetNumFilterOrder() const
Returns:

Order of coefficients.

inline bool IsTransposition() const
Returns:

True if transposed form is used.

inline bool IsValid() const
Returns:

True if this object is valid.

bool Run(const std::vector<double> &filter_coefficients, double filter_input, double *filter_output, AllPoleDigitalFilter::Buffer *buffer) const
Parameters:

  • filter_coefficients – [in] \(M\)-th order LPC coefficients.

  • filter_input – [in] Input signal.

  • filter_output – [out] Output signal.

  • buffer – [inout] Buffer.

Returns:

True on success, false on failure.

bool Run(const std::vector<double> &filter_coefficients, double *input_and_output, AllPoleDigitalFilter::Buffer *buffer) const
Parameters:

  • filter_coefficients – [in] \(M\)-th order LPC coefficients.

  • input_and_output – [inout] Input/output signal.

  • buffer – [inout] Buffer.

Returns:

True on success, false on failure.

class Buffer

Buffer for AllPoleDigitalFilter class.