diff options
Diffstat (limited to 'intern/audaspace/FX/AUD_HighpassCalculator.cpp')
-rw-r--r-- | intern/audaspace/FX/AUD_HighpassCalculator.cpp | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/intern/audaspace/FX/AUD_HighpassCalculator.cpp b/intern/audaspace/FX/AUD_HighpassCalculator.cpp new file mode 100644 index 00000000000..573bba1c62b --- /dev/null +++ b/intern/audaspace/FX/AUD_HighpassCalculator.cpp @@ -0,0 +1,27 @@ +#include "AUD_HighpassCalculator.h" + +#include <cmath> + +#ifndef M_PI +#define M_PI 3.14159265358979323846 +#endif + +AUD_HighpassCalculator::AUD_HighpassCalculator(float frequency, float Q) : + m_frequency(frequency), + m_Q(Q) +{ +} + +void AUD_HighpassCalculator::recalculateCoefficients(AUD_SampleRate rate, std::vector<float> &b, std::vector<float> &a) +{ + float w0 = 2.0 * M_PI * (AUD_SampleRate)m_frequency / rate; + float alpha = (float)(sin(w0) / (2.0 * (double)m_Q)); + float norm = 1 + alpha; + float c = cos(w0); + a.push_back(1); + a.push_back(-2 * c / norm); + a.push_back((1 - alpha) / norm); + b.push_back((1 + c) / (2 * norm)); + b.push_back((-1 - c) / norm); + b.push_back(b[0]); +} |