From 1fad862eea514dd1cf425faca1165fb937e9ac0c Mon Sep 17 00:00:00 2001 From: Clyne Sullivan Date: Wed, 5 Jun 2024 17:53:35 -0400 Subject: [PATCH] fix qfplib dependence; clean up filter() --- Makefile | 2 +- main.cpp | 18 +++++++++--------- sos-iir-filter.h | 39 +++++++++++++++++++-------------------- 3 files changed, 29 insertions(+), 30 deletions(-) diff --git a/Makefile b/Makefile index 1065763..bfd4c37 100644 --- a/Makefile +++ b/Makefile @@ -15,7 +15,7 @@ endif # C++ specific options here (added to USE_OPT). ifeq ($(USE_CPPOPT),) - USE_CPPOPT = -std=c++23 -fno-exceptions -fno-rtti + USE_CPPOPT = -std=c++23 -fno-exceptions -fno-rtti -fno-threadsafe-statics endif # Enable this if you want the linker to remove unused code and data. diff --git a/main.cpp b/main.cpp index 2db9ec8..da1722f 100644 --- a/main.cpp +++ b/main.cpp @@ -9,9 +9,9 @@ static constexpr auto& WEIGHTING = A_weighting; static constexpr auto& MIC_EQUALIZER = SPH0645LM4H_B_RB; -static constexpr float MIC_OFFSET_DB ( 0.f); // Linear offset -static constexpr float MIC_SENSITIVITY (-26.f); // dBFS value expected at MIC_REF_DB -static constexpr float MIC_REF_DB ( 94.f); // dB where sensitivity is specified +static constexpr sos_t MIC_OFFSET_DB ( 0.f); // Linear offset +static constexpr sos_t MIC_SENSITIVITY (-26.f); // dBFS value expected at MIC_REF_DB +static constexpr sos_t MIC_REF_DB ( 94.f); // dB where sensitivity is specified static constexpr sos_t MIC_OVERLOAD_DB (120.f); // dB - Acoustic overload point static constexpr sos_t MIC_NOISE_DB ( 29.f); // dB - Noise floor static constexpr auto MIC_BITS = 18u; @@ -21,8 +21,8 @@ static constexpr unsigned I2S_BUFSIZ = 1024; static constexpr unsigned I2S_STRIDE = 16; // Calculate reference amplitude value at compile time -static const auto MIC_REF_AMPL = qfp_fpow(10.f, MIC_SENSITIVITY / 20) * - ((1 << (MIC_BITS - 1)) - 1); +static const auto MIC_REF_AMPL = sos_t((1 << (MIC_BITS - 1)) - 1) * + qfp_fpow(10.f, MIC_SENSITIVITY / 20.f); static SEMAPHORE_DECL(i2sReady, 0); static THD_WORKING_AREA(waThread1, 128); @@ -83,13 +83,13 @@ THD_FUNCTION(Thread1, arg) palSetPad(GPIOB, 7); chSemWait(&i2sReady); - const auto Leq_RMS = qfp_fsqrt((float)Leq_sum_sqr / Leq_samples); - const auto Leq_dB = MIC_OFFSET_DB + MIC_REF_DB + 20 * + const sos_t Leq_RMS = qfp_fsqrt(Leq_sum_sqr / qfp_uint2float(Leq_samples)); + const sos_t Leq_dB = MIC_OFFSET_DB + MIC_REF_DB + sos_t(20.f) * qfp_flog10(Leq_RMS / MIC_REF_AMPL); Leq_sum_sqr = sos_t(0.f); Leq_samples = 0; - auto n = std::clamp(static_cast(Leq_dB), 0l, 999l); + auto n = std::clamp(qfp_float2int(Leq_dB), 0, 999); strbuf[2] = n % 10 + '0'; n /= 10; strbuf[1] = n % 10 + '0'; n /= 10; strbuf[0] = n ? n + '0' : ' '; @@ -111,7 +111,7 @@ void i2sCallback(I2SDriver *i2s) std::ranges::copy( std::views::counted(i2sBuffer.begin() + offset, halfsize / I2S_STRIDE) | std::ranges::views::stride(2) - | std::views::transform([](uint32_t s) { return sos_t(fixsample(s)); }), + | std::views::transform([](uint32_t s) { return sos_t(qfp_int2float(fixsample(s))); }), samples); auto samps = std::views::counted(samples, halfsize / (2 * I2S_STRIDE)); diff --git a/sos-iir-filter.h b/sos-iir-filter.h index 4d345f1..c827ef9 100644 --- a/sos-iir-filter.h +++ b/sos-iir-filter.h @@ -32,34 +32,36 @@ extern "C" { float qfp_fpow(float b, float e) { - return qfp_fexp(e * qfp_fln(b)); + return qfp_fexp(qfp_fmul(e, qfp_fln(b))); } float qfp_flog10(float x) { - return qfp_fln(x) / qfp_fln(10); + static const auto ln10 = qfp_fln(10.f); + return qfp_fdiv(qfp_fln(x), ln10); } -struct sos_t +class sos_t { float v; +public: constexpr sos_t(float v_ = 0.f): v(v_) {} - sos_t operator+(const sos_t& o) const noexcept { - return qfp_fadd(v, o.v); + sos_t operator+(auto x) const noexcept { + return qfp_fadd(v, x); } sos_t operator-(const sos_t& o) const noexcept { return qfp_fsub(v, o.v); } - sos_t operator*(const sos_t& o) const noexcept { - return qfp_fmul(v, o.v); + sos_t operator*(auto x) const noexcept { + return qfp_fmul(v, x); } - sos_t operator/(const sos_t& o) const noexcept { - return qfp_fdiv(v, o.v); + sos_t operator/(auto x) const noexcept { + return qfp_fdiv(v, x); } sos_t& operator+=(const sos_t& o) noexcept { @@ -100,17 +102,14 @@ struct SOS_IIR_Filter { } void filter(auto samples, std::size_t n = N) { - for ([[maybe_unused]] auto _ : std::views::zip_transform( - [](auto samps, const auto& coeffs, auto& ww) { - // Assumes a0 and b0 coefficients are one (1.0) - for (auto& s : samps) { - auto f6 = s + coeffs.a1 * ww.w0 + coeffs.a2 * ww.w1; - s = f6 + coeffs.b1 * ww.w0 + coeffs.b2 * ww.w1; - ww.w1 = std::exchange(ww.w0, f6); - } - return 0; - }, - std::views::repeat(samples, n), sos, w)) {} + for (auto [coeffs, ww] : std::views::zip(sos, w) | std::views::take(n)) { + // Assumes a0 and b0 coefficients are one (1.0) + for (auto& s : samples) { + auto f6 = s + coeffs.a1 * ww.w0 + coeffs.a2 * ww.w1; + s = f6 + coeffs.b1 * ww.w0 + coeffs.b2 * ww.w1; + ww.w1 = std::exchange(ww.w0, f6); + } + } } sos_t filter_sum_sqr(auto samples) {