diff options
Diffstat (limited to 'core/bs2b.cpp')
| -rw-r--r-- | core/bs2b.cpp | 127 |
1 files changed, 64 insertions, 63 deletions
diff --git a/core/bs2b.cpp b/core/bs2b.cpp index 303bf9bd..9157c4d7 100644 --- a/core/bs2b.cpp +++ b/core/bs2b.cpp @@ -26,72 +26,74 @@ #include <algorithm> #include <cmath> #include <iterator> +#include <stdexcept> #include "alnumbers.h" #include "bs2b.h" +namespace { /* Set up all data. */ -static void init(struct bs2b *bs2b) +void init(Bs2b::bs2b *bs2b) { float Fc_lo, Fc_hi; float G_lo, G_hi; - float x, g; switch(bs2b->level) { - case BS2B_LOW_CLEVEL: /* Low crossfeed level */ + case Bs2b::LowCLevel: /* Low crossfeed level */ Fc_lo = 360.0f; Fc_hi = 501.0f; G_lo = 0.398107170553497f; G_hi = 0.205671765275719f; break; - case BS2B_MIDDLE_CLEVEL: /* Middle crossfeed level */ + case Bs2b::MiddleCLevel: /* Middle crossfeed level */ Fc_lo = 500.0f; Fc_hi = 711.0f; G_lo = 0.459726988530872f; G_hi = 0.228208484414988f; break; - case BS2B_HIGH_CLEVEL: /* High crossfeed level (virtual speakers are closer to itself) */ + case Bs2b::HighCLevel: /* High crossfeed level (virtual speakers are closer to itself) */ Fc_lo = 700.0f; Fc_hi = 1021.0f; G_lo = 0.530884444230988f; G_hi = 0.250105790667544f; break; - case BS2B_LOW_ECLEVEL: /* Low easy crossfeed level */ + case Bs2b::LowECLevel: /* Low easy crossfeed level */ Fc_lo = 360.0f; Fc_hi = 494.0f; G_lo = 0.316227766016838f; G_hi = 0.168236228897329f; break; - case BS2B_MIDDLE_ECLEVEL: /* Middle easy crossfeed level */ + case Bs2b::MiddleECLevel: /* Middle easy crossfeed level */ Fc_lo = 500.0f; Fc_hi = 689.0f; G_lo = 0.354813389233575f; G_hi = 0.187169483835901f; break; - default: /* High easy crossfeed level */ - bs2b->level = BS2B_HIGH_ECLEVEL; + case Bs2b::HighECLevel: /* High easy crossfeed level */ + default: + bs2b->level = Bs2b::HighECLevel; Fc_lo = 700.0f; Fc_hi = 975.0f; G_lo = 0.398107170553497f; G_hi = 0.205671765275719f; break; - } /* switch */ + } - g = 1.0f / (1.0f - G_hi + G_lo); + float g{1.0f / (1.0f - G_hi + G_lo)}; /* $fc = $Fc / $s; * $d = 1 / 2 / pi / $fc; * $x = exp(-1 / $d); */ - x = std::exp(-al::numbers::pi_v<float>*2.0f*Fc_lo/static_cast<float>(bs2b->srate)); + float x{ std::exp(-al::numbers::pi_v<float>*2.0f*Fc_lo/static_cast<float>(bs2b->srate))}; bs2b->b1_lo = x; bs2b->a0_lo = G_lo * (1.0f - x) * g; @@ -99,85 +101,84 @@ static void init(struct bs2b *bs2b) bs2b->b1_hi = x; bs2b->a0_hi = (1.0f - G_hi * (1.0f - x)) * g; bs2b->a1_hi = -x * g; -} /* init */ +} +} // namespace /* Exported functions. * See descriptions in "bs2b.h" */ +namespace Bs2b { -void bs2b_set_params(struct bs2b *bs2b, int level, int srate) -{ - if(srate <= 0) srate = 1; - - bs2b->level = level; - bs2b->srate = srate; - init(bs2b); -} /* bs2b_set_params */ - -int bs2b_get_level(struct bs2b *bs2b) +void bs2b::set_params(int level_, int srate_) { - return bs2b->level; -} /* bs2b_get_level */ + if(srate_ < 1) + throw std::runtime_error{"BS2B srate < 1"}; -int bs2b_get_srate(struct bs2b *bs2b) -{ - return bs2b->srate; -} /* bs2b_get_srate */ + level = level_; + srate = srate_; + init(this); +} -void bs2b_clear(struct bs2b *bs2b) +void bs2b::clear() { - std::fill(std::begin(bs2b->history), std::end(bs2b->history), bs2b::t_last_sample{}); -} /* bs2b_clear */ + history.fill(bs2b::t_last_sample{}); +} -void bs2b_cross_feed(struct bs2b *bs2b, float *Left, float *Right, size_t SamplesToDo) +void bs2b::cross_feed(float *RESTRICT Left, float *RESTRICT Right, size_t SamplesToDo) { - const float a0_lo{bs2b->a0_lo}; - const float b1_lo{bs2b->b1_lo}; - const float a0_hi{bs2b->a0_hi}; - const float a1_hi{bs2b->a1_hi}; - const float b1_hi{bs2b->b1_hi}; - float lsamples[128][2]; - float rsamples[128][2]; + const float a0lo{a0_lo}; + const float b1lo{b1_lo}; + const float a0hi{a0_hi}; + const float a1hi{a1_hi}; + const float b1hi{b1_hi}; + std::array<std::array<float,2>,128> samples; for(size_t base{0};base < SamplesToDo;) { - const size_t todo{std::min<size_t>(128, SamplesToDo-base)}; + const size_t todo{std::min(samples.size(), SamplesToDo-base)}; /* Process left input */ - float z_lo{bs2b->history[0].lo}; - float z_hi{bs2b->history[0].hi}; + float z_lo{history[0].lo}; + float z_hi{history[0].hi}; for(size_t i{0};i < todo;i++) { - lsamples[i][0] = a0_lo*Left[i] + z_lo; - z_lo = b1_lo*lsamples[i][0]; - - lsamples[i][1] = a0_hi*Left[i] + z_hi; - z_hi = a1_hi*Left[i] + b1_hi*lsamples[i][1]; + const float x{Left[i]}; + float y{a0hi*x + z_hi}; + z_hi = a1hi*x + b1hi*y; + samples[i][0] = y; + + y = a0lo*x + z_lo; + z_lo = b1lo*y; + samples[i][1] = y; } - bs2b->history[0].lo = z_lo; - bs2b->history[0].hi = z_hi; + history[0].lo = z_lo; + history[0].hi = z_hi; /* Process right input */ - z_lo = bs2b->history[1].lo; - z_hi = bs2b->history[1].hi; + z_lo = history[1].lo; + z_hi = history[1].hi; for(size_t i{0};i < todo;i++) { - rsamples[i][0] = a0_lo*Right[i] + z_lo; - z_lo = b1_lo*rsamples[i][0]; - - rsamples[i][1] = a0_hi*Right[i] + z_hi; - z_hi = a1_hi*Right[i] + b1_hi*rsamples[i][1]; + const float x{Right[i]}; + float y{a0lo*x + z_lo}; + z_lo = b1lo*y; + samples[i][0] += y; + + y = a0hi*x + z_hi; + z_hi = a1hi*x + b1hi*y; + samples[i][1] += y; } - bs2b->history[1].lo = z_lo; - bs2b->history[1].hi = z_hi; + history[1].lo = z_lo; + history[1].hi = z_hi; - /* Crossfeed */ for(size_t i{0};i < todo;i++) - *(Left++) = lsamples[i][1] + rsamples[i][0]; + *(Left++) = samples[i][0]; for(size_t i{0};i < todo;i++) - *(Right++) = rsamples[i][1] + lsamples[i][0]; + *(Right++) = samples[i][1]; base += todo; } -} /* bs2b_cross_feed */ +} + +} // namespace Bs2b |