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Biquad filter and design functions

biquad function

template <typename T, typename E1>
KFR_BIQUAD_DEPRECATED expression_iir<1, T, E1>
biquad(const biquad_section<T> &bq, E1 &&e1)

Returns template expressions that applies biquad filter to the input.
Param bq Biquad coefficients
Param e1 Input expression

template <size_t filters, typename T, typename E1>
KFR_BIQUAD_DEPRECATED expression_iir<filters, T, E1>
biquad(const biquad_section<T> (&bq)[filters], E1 &&e1)

Returns template expressions that applies cascade of biquad filters to the input.
Param bq Array of biquad coefficients
Param e1 Input expression
Note This implementation has zero latency

template <size_t maxfiltercount = 4, typename T,
          typename E1>
KFR_BIQUAD_DEPRECATED expression_handle<T, 1>
biquad(const biquad_section<T> *bq, size_t count, E1 &&e1)

Returns template expressions that applies cascade of biquad filters to the input.
Param bq Array of biquad coefficients
Param e1 Input expression
Note This implementation has zero latency

biquad_allpass function

template <typename T = fbase>
biquad_section<T> biquad_allpass(identity<T> frequency,
                                 identity<T> Q)

Calculates coefficients for the all-pass biquad filter
Param frequency Normalized frequency (frequency_Hz / samplerate_Hz)
Param Q Q factor
Returns Biquad filter coefficients

biquad_bandpass function

template <typename T = fbase>
biquad_section<T> biquad_bandpass(identity<T> frequency,
                                  identity<T> Q)

Calculates coefficients for the band-pass biquad filter
Param frequency Normalized frequency (frequency_Hz / samplerate_Hz)
Param Q Q factor
Returns Biquad filter coefficients

biquad_highpass function

template <typename T = fbase>
biquad_section<T> biquad_highpass(identity<T> frequency,
                                  identity<T> Q)

Calculates coefficients for the high-pass biquad filter
Param frequency Normalized frequency (frequency_Hz / samplerate_Hz)
Param Q Q factor
Returns Biquad filter coefficients

biquad_highshelf function

template <typename T = fbase>
biquad_section<T> biquad_highshelf(identity<T> frequency,
                                   identity<T> gain)

Calculates coefficients for the high-shelf biquad filter
Param frequency Normalized frequency (frequency_Hz / samplerate_Hz)
Param gain Gain in dB
Returns Biquad filter coefficients

biquad_l function

template <size_t filters, typename T, typename E1>
KFR_BIQUAD_DEPRECATED expression_iir_l<filters, T, E1>
biquad_l(const biquad_section<T> (&bq)[filters], E1 &&e1)

Returns template expressions that applies cascade of biquad filters to the input.
Param bq Array of biquad coefficients
Param e1 Input expression
Note This implementation introduces delay of N - 1 samples, where N is the filter count.

biquad_lowpass function

template <typename T = fbase>
biquad_section<T> biquad_lowpass(identity<T> frequency,
                                 identity<T> Q)

Calculates coefficients for the low-pass biquad filter
Param frequency Normalized frequency (frequency_Hz / samplerate_Hz)
Param Q Q factor
Returns Biquad filter coefficients

biquad_lowshelf function

template <typename T = fbase>
biquad_section<T> biquad_lowshelf(identity<T> frequency,
                                  identity<T> gain)

Calculates coefficients for the low-shelf biquad filter
Param frequency Normalized frequency (frequency_Hz / samplerate_Hz)
Param gain Gain in dB
Returns Biquad filter coefficients

biquad_notch function

template <typename T = fbase>
biquad_section<T> biquad_notch(identity<T> frequency,
                               identity<T> Q)

Calculates coefficients for the notch biquad filter
Param frequency Normalized frequency (frequency_Hz / samplerate_Hz)
Param Q Q factor
Returns Biquad filter coefficients

biquad_peak function

template <typename T = fbase>
biquad_section<T> biquad_peak(identity<T> frequency,
                              identity<T> Q,
                              identity<T> gain)

Calculates coefficients for the peak biquad filter
Param frequency Normalized frequency (frequency_Hz / samplerate_Hz)
Param Q Q factor
Param gain Gain in dB
Returns Biquad filter coefficients

biquad_section class

template <typename T> biquad_section

Structure for holding biquad filter coefficients.

iir function

template <size_t filters, typename T, typename E1>
expression_iir<filters, T, E1>
iir(E1 &&e1, iir_params<T, filters> params)

Returns template expressions that applies biquad filter to the input.
Param e1 Input expression
Param params Biquad coefficients

template <typename T, typename E1>
expression_handle<T, 1>
iir(E1 &&e1,
    const iir_params<T, tag_dynamic_vector> &params)

Returns template expressions that applies biquad filter to the input.
Param e1 Input expression
Param params Biquad coefficients

template <size_t filters, typename T, typename E1>
expression_iir<filters, T, E1, true>
iir(E1 &&e1,
    std::reference_wrapper<iir_state<T, filters>> state)

Returns template expressions that applies biquad filter to the input.
Param bq Biquad coefficients
Param e1 Input expression

Auto-generated from sources, Revision 6aea976a464de59d522d0c629e64bf0c044e6777, https://github.com/kfrlib/kfr/blob/6aea976a464de59d522d0c629e64bf0c044e6777/include/kfr/