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Correct samplerate-agnostic behaviour

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Vesa
2014-10-22 15:12:58 +03:00
parent 8e3908e785
commit eb86428f10
1 changed files with 9 additions and 7 deletions
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16
include/basic_filters.h
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@@ -117,8 +117,10 @@ public:
m_svq( 0.0f ),
m_doubleFilter( false ),
m_sampleRate( (float) _sample_rate ),
m_sampleRatio( 1.0f / m_sampleRate ),
m_subFilter( NULL )
{
m_svsr = 1.0f - expf( -4646.39874051f / m_sampleRate );
clearHistory();
}
@@ -475,8 +477,7 @@ public:
}
inline void calcFilterCoeffs( float _freq, float _q
/*, const bool _q_is_bandwidth = false*/ )
inline void calcFilterCoeffs( float _freq, float _q )
{
// temp coef vars
_q = qMax( _q, minQ() );
@@ -545,7 +546,7 @@ public:
_freq = qBound( minFreq(), _freq, 20000.0f );
// [ 0 - 0.5 ]
const float f = _freq / m_sampleRate;
const float f = _freq * m_sampleRatio;
// (Empirical tunning)
m_p = ( 3.6f - 3.2f * f ) * f;
m_k = 2.0f * m_p - 1;
@@ -562,16 +563,16 @@ public:
if( m_type == Lowpass_SV )
{
m_svf1 = qBound( 0.0001f, _freq * 0.00004125f, 0.825f );
m_svf2 = qBound( 0.0001f, _freq * 0.00008250f, 0.825f );
const float f = qMax( minFreq(), _freq ) * m_sampleRatio;
m_svf1 = qMin( f * 2.0f, 0.825f );
m_svf2 = qMin( f * 4.0f, 0.825f );
m_svq = qMax( 0.0001f, 2.0f - ( _q * 0.1995f ) );
m_svsr = 2025.0f / m_sampleRate;
return;
}
// other filters
_freq = qBound( minFreq(), _freq, 20000.0f );
const float omega = F_2PI * _freq / m_sampleRate;
const float omega = F_2PI * _freq * m_sampleRatio;
const float tsin = sinf( omega );
const float tcos = cosf( omega );
//float alpha;
@@ -672,6 +673,7 @@ private:
bool m_doubleFilter;
float m_sampleRate;
float m_sampleRatio;
basicFilters<CHANNELS> * m_subFilter;
} ;