bw_iir{1,2}: fixed, updated doc
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@ -70,7 +70,7 @@ static inline void bw_iir1_reset(
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/*! <<<```
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* Computes and puts the initial output in `y_0` and the initial state in
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* `s_0`, given the initial input `x_0` and coefficients `b0`, `b1`, and
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* `b2`.
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* `a1`.
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*
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* The given coefficients must describe a stable filter.
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*
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@ -87,7 +87,7 @@ static inline void bw_iir1_reset_multi(
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/*! <<<```
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* Computes and puts each of the `n_channels` initial outputs in `y_0` and
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* initial states in `s_0`, given the corresponding initial inputs `x_0` and
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* coefficients `b0`, `b1`, and `b2`.
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* coefficients `b0`, `b1`, and `a1`.
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*
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* `y_0` and/or `s_0` may be `BW_NULL`, in which case the corresponding
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* values are not written anywhere.
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@ -104,7 +104,7 @@ static inline void bw_iir1_process1(
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float b1,
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float a1);
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/*! <<<```
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* Processes one input sample `x` using coefficients `b0`, `b1`, and `b2`.
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* Processes one input sample `x` using coefficients `b0`, `b1`, and `a1`.
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* The output sample and next state value are put in `y` and `s`
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* respectively.
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*
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@ -123,7 +123,7 @@ static inline void bw_iir1_process(
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/*! <<<```
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* Processes the first `n_samples` of the input buffer `x` and fills the
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* first `n_samples` of the output buffer `y`, while using coefficients `b0`,
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* `b1`, and `b2`. The next state value is put in `s`.
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* `b1`, and `a1`. The next state value is put in `s`.
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*
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* The given coefficients must describe a stable filter.
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*
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@ -141,7 +141,7 @@ static inline void bw_iir1_process_multi(
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/*! <<<```
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* Processes the first `n_samples` of the `n_channels` input buffers `x` and
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* fills the first `n_samples` of the `n_channels` output buffers `y`, while
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* using coefficients `b0`, `b1`, and `b2`. The next `n_channels` state
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* using coefficients `b0`, `b1`, and `a1`. The next `n_channels` state
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* values are put in `s`.
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*
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* The given coefficients must describe a stable filter.
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@ -162,11 +162,11 @@ static inline void bw_iir1_coeffs_ap1(
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* at high frequencies) with unitary gain, using the bilinear transform with
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* prewarping.
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*
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* It takes the `sample_rate` (Hz, must be positive) and the `cutoff`
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* frequency (Hz, in [`1e-6f`, `1e12f`]). If `prewarp_freq` is `0`, then the
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* prewarping frequency matches `cutoff`, otherwise the value specified by
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* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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* It takes the `sample_rate` (Hz, must be finite and positive) and the
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* `cutoff` frequency (Hz, in [`1e-6f`, `1e12f`]). If `prewarp_freq` is `0`,
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* then the prewarping frequency matches `cutoff`, otherwise the value
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* specified by `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally
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* limited to avoid instability) is used.
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*
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* #### bw_iir1_coeffs_hp1()
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* ```>>> */
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@ -184,11 +184,11 @@ static inline void bw_iir1_coeffs_hp1(
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* approaching unity as frequency increases, using the bilinear transform
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* with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be positive) and the `cutoff`
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* frequency (Hz, in [`1e-6f`, `1e12f`]). If `prewarp_freq` is `0`, then the
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* prewarping frequency matches `cutoff`, otherwise the value specified by
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* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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* It takes the `sample_rate` (Hz, must be finite and positive) and the
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* `cutoff` frequency (Hz, in [`1e-6f`, `1e12f`]). If `prewarp_freq` is `0`,
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* then the prewarping frequency matches `cutoff`, otherwise the value
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* specified by `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally
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* limited to avoid instability) is used.
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*
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* #### bw_iir1_coeffs_hs1()
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* ```>>> */
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@ -207,13 +207,16 @@ static inline void bw_iir1_coeffs_hs1(
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* a first-order high shelf filter (6 dB/oct) with unitary DC gain, using the
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* bilinear transform with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be positive), the `cutoff` frequency
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* (Hz, in [`1e-6f`, `1e12f`]), and the high-frequency gain `high_gain`,
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* either as linear gain (in [1e-30f, 1e30f]) if `high_gain_dB` is `0`, or
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* otherwise in dB (in [-600.f, 600.f]). If `prewarp_freq` is `0`, then the
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* prewarping frequency matches `cutoff`, otherwise the value specified by
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* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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* It takes the `sample_rate` (Hz, must be finite and positive), the `cutoff`
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* frequency (Hz, must be finite and positive), and the high-frequency gain
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* `high_gain`, either as linear gain (in [`1e-30f`, `1e30f`]) if
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* `high_gain_dB` is `0`, or otherwise in dB (in [`-600.f`, `600.f`]). If
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* `prewarp_freq` is `0`, then the prewarping frequency matches `cutoff`,
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* otherwise the value specified by `prewarp_freq` (Hz, in [`1e-6f`,
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* `1e12f`], however interally limited to avoid instability) is used.
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*
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* `cutoff * bw_sqrtf(high_gain)` must be in [`1e-6f`, `1e12f`], where
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* `high_gain` is expressed as linear gain.
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*
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* #### bw_iir1_coeffs_lp1()
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* ```>>> */
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@ -230,11 +233,11 @@ static inline void bw_iir1_coeffs_lp1(
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* a first-order lowpass filter (6 dB/oct) with unitary DC gain, using the
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* bilinear transform with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be positive) and the `cutoff`
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* frequency (Hz, in [`1e-6f`, `1e12f`]). If `prewarp_freq` is `0`, then the
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* prewarping frequency matches `cutoff`, otherwise the value specified by
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* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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* It takes the `sample_rate` (Hz, must be finite and positive) and the
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* `cutoff` frequency (Hz, in [`1e-6f`, `1e12f`]). If `prewarp_freq` is `0`,
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* then the prewarping frequency matches `cutoff`, otherwise the value
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* specified by `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally
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* limited to avoid instability) is used.
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*
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* #### bw_iir1_coeffs_ls1()
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* ```>>> */
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@ -253,13 +256,16 @@ static inline void bw_iir1_coeffs_ls1(
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* a first-order high shelf filter (6 dB/oct) with unitary DC gain, using the
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* bilinear transform with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be positive), the `cutoff` frequency
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* (Hz, in [`1e-6f`, `1e12f`]), and the `dc_gain`, either as linear gain
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* (in [1e-30f, 1e30f]) if `dc_gain_dB` is `0`, or otherwise in dB (in
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* [-600.f, 600.f]). If `prewarp_freq` is `0`, then the prewarping frequency
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* matches `cutoff`, otherwise the value specified by `prewarp_freq` (Hz, in
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* [`1e-6f`, `1e12f`], however interally limited to avoid instability) is
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* used.
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* It takes the `sample_rate` (Hz, must be finite and positive), the
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* `cutoff` frequency (Hz, must be finite and positive), and the `dc_gain`,
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* either as linear gain (in [`1e-30f`, `1e30f`]) if `dc_gain_dB` is `0`, or
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* otherwise in dB (in [`-600.f`, `600.f`]). If `prewarp_freq` is `0`, then
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* the prewarping frequency matches `cutoff`, otherwise the value specified
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* by `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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*
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* `cutoff * bw_rcpf(bw_sqrtf(dc_gain))` must be in [`1e-6f`, `1e12f`], where
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* `dc_gain` is expressed as linear gain.
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*
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* #### bw_iir1_coeffs_mm1()
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* ```>>> */
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@ -283,9 +289,9 @@ static inline void bw_iir1_coeffs_mm1(
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* where fc is the cutoff frequency, using the bilinear transform with
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* prewarping.
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*
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* It takes the `sample_rate` (Hz, must be positive), the `cutoff` frequency
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* (Hz, in [`1e-6f`, `1e12f`]), and output coefficients `coeff_x` and
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* `coeff_lp` (both must be finite). If `prewarp_freq` is `0`, then the
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* It takes the `sample_rate` (Hz, must be finite and positive), the `cutoff`
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* frequency (Hz, in [`1e-6f`, `1e12f`]), and output coefficients `coeff_x`
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* and `coeff_lp` (both must be finite). If `prewarp_freq` is `0`, then the
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* prewarping frequency matches `cutoff`, otherwise the value specified by
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* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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@ -71,7 +71,11 @@ static inline void bw_iir2_reset(
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float a1,
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float a2);
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/*! <<<```
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* XXX.
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* Computes and puts the initial output in `y_0` and the initial states in
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* `s1_0` and `s2_0`, given the initial input `x_0` and coefficients `b0`,
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* `b1`, `b2`, `a1`, and `a2`.
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*
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* The given coefficients must describe a stable filter.
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*
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* #### bw_iir2_reset_multi()
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* ```>>> */
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@ -87,7 +91,14 @@ static inline void bw_iir2_reset_multi(
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float a2,
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size_t n_channels);
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/*! <<<```
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* XXX.
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* Computes and puts each of the `n_channels` initial outputs in `y_0` and
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* initial states in `s1_0` and `s2_0`, given the corresponding initial
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* inputs `x_0` and coefficients `b0`, `b1`, `b2`, `a1`, and `a2`.
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*
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* `y_0` and/or `s_0` may be `BW_NULL`, in which case the corresponding
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* values are not written anywhere.
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*
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* The given coefficients must describe a stable filter.
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*
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* #### bw_iir2_process1()
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* ```>>> */
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@ -102,7 +113,11 @@ static inline void bw_iir2_process1(
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float a1,
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float a2);
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/*! <<<```
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* XXX.
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* Processes one input sample `x` using coefficients `b0`, `b1`, `b2`, `a1`,
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* and `a2`. The output sample and next states value are put in `y` and
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* `s1`/`s2` respectively.
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*
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* The given coefficients must describe a stable filter.
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*
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* #### bw_iir2_process()
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* ```>>> */
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@ -118,7 +133,11 @@ static inline void bw_iir2_process(
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float a2,
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size_t n_samples);
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/*! <<<```
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* XXX
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* Processes the first `n_samples` of the input buffer `x` and fills the
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* first `n_samples` of the output buffer `y`, while using coefficients `b0`,
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* `b1`, `b2, `a1`, and `a2`. The next state values are put in `s1` and `s2`.
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*
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* The given coefficients must describe a stable filter.
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*
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* #### bw_iir2_process_multi()
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* ```>>> */
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@ -135,7 +154,12 @@ static inline void bw_iir2_process_multi(
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size_t n_channels,
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size_t n_samples);
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/*! <<<```
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* XXX
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* Processes the first `n_samples` of the `n_channels` input buffers `x` and
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* fills the first `n_samples` of the `n_channels` output buffers `y`, while
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* using coefficients `b0`, `b1`, `b2`, `a1`, and `a2`. The next `n_channels`
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* state values are put in `s1` and `s2`.
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*
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* The given coefficients must describe a stable filter.
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*
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* #### bw_iir2_coeffs_ap2()
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* ```>>> */
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@ -151,7 +175,17 @@ static inline void bw_iir2_coeffs_ap2(
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float * BW_RESTRICT a1,
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float * BW_RESTRICT a2);
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/*! <<<```
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* XXX
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* Computes and puts coefficient values in `b0`, `b1`, `b2`, `a1`, and `a2`
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* resulting in a second-order allpass filter (180° shift at cutoff,
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* approaching 360° shift at high frequencies) with unitary gain, using the
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* bilinear transform with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be positive), the `cutoff` frequency
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* (Hz, in [`1e-6f`, `1e12f`]), and the quality factor `Q` (in [`1e-6f`,
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* `1e6f`]). If `prewarp_freq` is `0`, then the prewarping frequency matches
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* `cutoff`, otherwise the value specified by `prewarp_freq` (Hz, in
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* [`1e-6f`, `1e12f`], however interally limited to avoid instability) is
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* used.
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*
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* #### bw_iir2_coeffs_bp2()
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* ```>>> */
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@ -167,7 +201,16 @@ static inline void bw_iir2_coeffs_bp2(
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float * BW_RESTRICT a1,
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float * BW_RESTRICT a2);
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/*! <<<```
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* XXX
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* Computes and puts coefficient values in `b0`, `b1`, `b2`, `a1`, and `a2`
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* resulting in a second-order bandpass filter (6 dB/oct) with peak gain
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* `Q` (linear gain), using the bilinear transform with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be finite and positive), the `cutoff`
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* frequency (Hz, in [`1e-6f`, `1e12f`]), and the quality factor `Q` (in
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* [`1e-6f`, `1e6f`]). If `prewarp_freq` is `0`, then the prewarping
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* frequency matches `cutoff`, otherwise the value specified by
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* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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*
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* #### bw_iir2_coeffs_hp2()
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* ```>>> */
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@ -183,7 +226,17 @@ static inline void bw_iir2_coeffs_hp2(
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float * BW_RESTRICT a1,
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float * BW_RESTRICT a2);
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/*! <<<```
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* XXX
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* Computes and puts coefficient values in `b0`, `b1`, `b2`, `a1`, and `a2`
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* resulting in a second-order highpass filter (12 dB/oct) with gain
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* asymptotically approaching unity as frequency increases, using the
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* bilinear transform with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be finite and positive), the `cutoff`
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* frequency (Hz, in [`1e-6f`, `1e12f`]), and the quality factor `Q` (in
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* [`1e-6f`, `1e6f`]). If `prewarp_freq` is `0`, then the prewarping
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* frequency matches `cutoff`, otherwise the value specified by
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* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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*
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* #### bw_iir2_coeffs_hs2()
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* ```>>> */
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@ -201,7 +254,21 @@ static inline void bw_iir2_coeffs_hs2(
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float * BW_RESTRICT a1,
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float * BW_RESTRICT a2);
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/*! <<<```
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* XXX
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* Computes and puts coefficient values in `b0`, `b1`, `b2`, `a1,` and `a2`
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* resulting in a second-order high shelf filter (12 dB/oct) with unitary DC
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* gain, using the bilinear transform with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be finite and positive), the `cutoff`
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* frequency (Hz, must be finite and positive), the quality factor `Q` (in
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* [`1e-6f`, `1e6f`]), and the high-frequency gain `high_gain`, either as
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* linear gain (in [`1e-30f`, `1e30f`]) if `high_gain_dB` is `0`, or
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* otherwise in dB (in [`-600.f`, `600.f`]). If `prewarp_freq` is `0`, then
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* the prewarpingfrequency matches `cutoff`, otherwise the value specified by
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* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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*
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* `cutoff * bw_sqrtf(bw_sqrtf(high_gain))` must be in [`1e-6f`, `1e12f`],
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* where `high_gain` is expressed as linear gain.
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*
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* #### bw_iir2_coeffs_lp2()
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* ```>>> */
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@ -217,7 +284,16 @@ static inline void bw_iir2_coeffs_lp2(
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float * BW_RESTRICT a1,
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float * BW_RESTRICT a2);
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/*! <<<```
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* XXX
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* Computes and puts coefficient values in `b0`, `b1`, `b2`, `a1`, and `a2`
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* resulting in a second-order lowpass filter (12 dB/oct) with unitary DC
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* gain, using the bilinear transform with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be finite and positive), the `cutoff`
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* frequency (Hz, in [`1e-6f`, `1e12f`]), and the quality factor `Q` (in
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* [`1e-6f`, `1e6f`]). If `prewarp_freq` is `0`, then the prewarping
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* frequency matches `cutoff`, otherwise the value specified by
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* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
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* avoid instability) is used.
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*
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* #### bw_iir2_coeffs_ls2()
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* ```>>> */
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@ -235,7 +311,22 @@ static inline void bw_iir2_coeffs_ls2(
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float * BW_RESTRICT a1,
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float * BW_RESTRICT a2);
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/*! <<<```
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* XXX
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* Computes and puts coefficient values in `b0`, `b1`, `b2`, `a1,` and `a2`
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* resulting in a second-order low shelf filter (12 dB/oct) with gain
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* asymptotically approaching unity as frequency increases, using the
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* bilinear transform with prewarping.
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*
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* It takes the `sample_rate` (Hz, must be finite and positive), the `cutoff`
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* frequency (Hz, must be finite and positive), the quality factor `Q` (in
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* [`1e-6f`, `1e6f`]), and the `dc_gain`, either as linear gain (in
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* [`1e-30f`, `1e30f`]) if `high_gain_dB` is `0`, or otherwise in dB (in
|
||||
* [`-600.f`, `600.f`]). If `prewarp_freq` is `0`, then the prewarping
|
||||
* frequency matches `cutoff`, otherwise the value specified by
|
||||
* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
|
||||
* avoid instability) is used.
|
||||
*
|
||||
* `cutoff * bw_rpcf(bw_sqrtf(bw_sqrtf(dc_gain)))` must be in [`1e-6f`,
|
||||
* `1e12f`], where `dc_gain` is expressed as linear gain.
|
||||
*
|
||||
* #### bw_iir2_coeffs_mm2()
|
||||
* ```>>> */
|
||||
@ -255,7 +346,23 @@ static inline void bw_iir2_coeffs_mm2(
|
||||
float * BW_RESTRICT a1,
|
||||
float * BW_RESTRICT a2);
|
||||
/*! <<<```
|
||||
* XXX
|
||||
* Computes and puts coefficient values in `b0`, `b1`, `b2`, `a1`, and `a2`
|
||||
* resulting in a second-order filter implementing an approximation of the
|
||||
* Laplace-domain transfer function
|
||||
*
|
||||
* > H(s) = coeff\_x + (coeff\_hp s^2 + 2 pi fc s coeff\_bp
|
||||
* > + (2 pi fc)^2 coeff\_lp) / (s^2 + 2 pi fc / Q s + (2 pi fc)^2)
|
||||
*
|
||||
* where fc is the cutoff frequency and Q is the quality factor, using the
|
||||
* bilinear transform with prewarping.
|
||||
*
|
||||
* It takes the `sample_rate` (Hz, must be finite and positive), the `cutoff`
|
||||
* frequency (Hz, in [`1e-6f`, `1e12f`]), the quality factor `Q` (in
|
||||
* [`1e-6f`, `1e6f`]), and output coefficients `coeff_x`, `coeff_lp`,
|
||||
* `coeff_bp`, `coeff_hp` (all must be finite). If `prewarp_freq` is `0`,
|
||||
* then the prewarping frequency matches `cutoff`, otherwise the value
|
||||
* specified by `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally
|
||||
* limited to avoid instability) is used.
|
||||
*
|
||||
* #### bw_iir2_coeffs_notch()
|
||||
* ```>>> */
|
||||
@ -271,7 +378,17 @@ static inline void bw_iir2_coeffs_notch(
|
||||
float * BW_RESTRICT a1,
|
||||
float * BW_RESTRICT a2);
|
||||
/*! <<<```
|
||||
* XXX
|
||||
* Computes and puts coefficient values in `b0`, `b1`, `b2`, `a1`, and `a2`
|
||||
* resulting in a second-order notch filter with unitary gain at DC and
|
||||
* asymptotically as frequency increases, and null gain at cutoff frequency,
|
||||
* using the bilinear transform with prewarping.
|
||||
*
|
||||
* It takes the `sample_rate` (Hz, must be finite and positive), the `cutoff`
|
||||
* frequency (Hz, in [`1e-6f`, `1e12f`]), and the quality factor `Q` (in
|
||||
* [`1e-6f`, `1e6f`]). If `prewarp_freq` is `0`, then the prewarping
|
||||
* frequency matches `cutoff`, otherwise the value specified by
|
||||
* `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally limited to
|
||||
* avoid instability) is used.
|
||||
*
|
||||
* #### bw_iir2_coeffs_peak()
|
||||
* ```>>> */
|
||||
@ -290,7 +407,25 @@ static inline void bw_iir2_coeffs_peak(
|
||||
float * BW_RESTRICT a1,
|
||||
float * BW_RESTRICT a2);
|
||||
/*! <<<```
|
||||
* XXX
|
||||
* Computes and puts coefficient values in `b0`, `b1`, and `a1` resulting in
|
||||
* a second-order peak filter with unitary gain at DC and asymptotically as
|
||||
* frequency increases, using the bilinear transform with prewarping.
|
||||
*
|
||||
* It takes the `sample_rate` (Hz, must be finite and positive), the
|
||||
* `cutoff` frequency (Hz, in [`1e-6f`, `1e12f`]), and the `peak_gain`,
|
||||
* either as linear gain (in [`1e-30f`, `1e30f`]) if `peak_gain_dB` is `0`,
|
||||
* or otherwise in dB (in [`-600.f`, `600.f`]). `Q_bandwidth` indicates
|
||||
* either the quality factor (in [`1e-6f`, `1e6f`]) if `use_bandwidth` is
|
||||
* `0`, or otherwise the bandwidth (octaves, in [`1e-6f`, `90.f`]),
|
||||
* designating the distance between midpoint gain frequencies (i.e.,
|
||||
* frequencies with gain = peak gain / 2 in dB terms). If `prewarp_freq` is
|
||||
* `0`, then the prewarping frequency matches `cutoff`, otherwise the value
|
||||
* specified by `prewarp_freq` (Hz, in [`1e-6f`, `1e12f`], however interally
|
||||
* limited to avoid instability) is used.
|
||||
*
|
||||
* If `use_bandwidth` is non-`0`, then `bw_sqrtf(bw_pow2f(Q_bandwidth) *
|
||||
* peak_gain) * bw_rcpf(bw_pow2f(Q_bandwidth) - 1.f)` must be in [`1e-6f`,
|
||||
* `1e6f`], where `peak_gain` is expressed as linear gain.
|
||||
* }}} */
|
||||
|
||||
#if !defined(BW_CXX_NO_EXTERN_C) && defined(__cplusplus)
|
||||
|
||||
Loading…
Reference in New Issue
Block a user