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Crossover EQ initial commit, also fix bugs in LR4 filter and Fader

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This commit is contained in:
Vesa
2014-12-15 10:41:43 +02:00
parent 7b61c54f3a
commit 0789bae53a
15 changed files with 728 additions and 37 deletions
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81
include/BasicFilters.h
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@@ -64,6 +64,7 @@ public:
for( int i = 0; i < CHANNELS; ++i )
{
m_z1[i] = m_z2[i] = m_z3[i] = m_z4[i] = 0.0f;
m_y1[i] = m_y2[i] = m_y3[i] = m_y4[i] = 0.0f;
}
}
@@ -75,69 +76,89 @@ public:
inline void setCoeffs( float freq )
{
// wc
const float wc = F_2PI * freq / m_sampleRate;
const float wc2 = wc * wc;
const float wc3 = wc2 * wc;
const double wc = D_2PI * freq;
const double wc2 = wc * wc;
const double wc3 = wc2 * wc;
m_wc4 = wc2 * wc2;
// k
const float k = wc / tan( wc * 0.5 );
const float k2 = k * k;
const float k3 = k2 * k;
const double k = wc / tan( D_PI * freq / m_sampleRate );
const double k2 = k * k;
const double k3 = k2 * k;
m_k4 = k2 * k2;
// a
static const double sqrt2 = sqrt( 2.0 );
const float sq_tmp1 = sqrt2 * wc3 * k;
const float sq_tmp2 = sqrt2 * wc * k3;
m_a = 1.0f / ( 4.0f * wc2 * k2 + 2.0f * sq_tmp1 + m_k4 + 2.0f * sq_tmp2 + m_wc4 );
const double sq_tmp1 = sqrt2 * wc3 * k;
const double sq_tmp2 = sqrt2 * wc * k3;
m_a = 1.0 / ( 4.0 * wc2 * k2 + 2.0 * sq_tmp1 + m_k4 + 2.0 * sq_tmp2 + m_wc4 );
// b
m_b1 = ( 4.0f * ( m_wc4 + sq_tmp1 - m_k4 - sq_tmp2 ) ) * m_a;
m_b2 = ( 6.0f * m_wc4 - 8.0f * wc2 * k2 + 6.0f * m_k4 ) * m_a;
m_b3 = ( 4.0f * ( m_wc4 - sq_tmp1 + sq_tmp2 - m_k4 ) ) * m_a;
m_b4 = ( m_k4 - 2.0f * sq_tmp1 + m_wc4 - 2.0f * sq_tmp2 + 4.0f * wc2 * k2 ) * m_a;
m_b1 = ( 4.0 * ( m_wc4 + sq_tmp1 - m_k4 - sq_tmp2 ) ) * m_a;
m_b2 = ( 6.0 * m_wc4 - 8.0 * wc2 * k2 + 6.0 * m_k4 ) * m_a;
m_b3 = ( 4.0 * ( m_wc4 - sq_tmp1 + sq_tmp2 - m_k4 ) ) * m_a;
m_b4 = ( m_k4 - 2.0 * sq_tmp1 + m_wc4 - 2.0 * sq_tmp2 + 4.0 * wc2 * k2 ) * m_a;
}
inline void setLowpass( float freq )
{
setCoeffs( freq );
m_a0 = m_wc4 * m_a;
m_a1 = 4.0f * m_a0;
m_a2 = 6.0f * m_a0;
m_a1 = 4.0 * m_a0;
m_a2 = 6.0 * m_a0;
}
inline void setHighpass( float freq )
{
setCoeffs( freq );
m_a0 = m_k4 * m_a;
m_a1 = 4.0f * m_a0;
m_a2 = 6.0f * m_a0;
m_a1 = -4.0 * m_a0;
m_a2 = 6.0 * m_a0;
}
inline float update( float in, ch_cnt_t ch )
{
const float a0in = m_a0 * in;
const float a1in = m_a1 * in;
const float out = m_z1[ch] + a0in;
const double y = m_a0 * in + ( m_z1[ch] * m_a1 ) + ( m_z2[ch] * m_a2 ) +
( m_z3[ch] * m_a1 ) + ( m_z4[ch] * m_a0 ) -
( m_y1[ch] * m_b1 ) - ( m_y2[ch] * m_b2 ) -
( m_y3[ch] * m_b3 ) - ( m_y4[ch] * m_b4 );
m_z4[ch] = m_z3[ch];
m_z3[ch] = m_z2[ch];
m_z2[ch] = m_z1[ch];
m_z1[ch] = in;
m_z1[ch] = a1in + m_z2[ch] - ( m_b1 * out );
m_z2[ch] = ( m_a2 * in ) + m_z3[ch] - ( m_b2 * out );
m_z3[ch] = a1in + m_z4[ch] - ( m_b3 * out );
m_z4[ch] = a0in - ( m_b4 * out );
m_y4[ch] = m_y3[ch];
m_y3[ch] = m_y2[ch];
m_y2[ch] = m_y1[ch];
m_y1[ch] = y;
return out;
return y;
// for some reason converting to direct form 2 doesn't seem to work for this filter
/* const double x = in - ( m_z1[ch] * m_b1 ) - ( m_z2[ch] * m_b2 ) -
( m_z3[ch] * m_b3 ) - ( m_z4[ch] * m_b4 );
m_z4[ch] = m_z3[ch];
m_z3[ch] = m_z2[ch];
m_z2[ch] = m_z1[ch];
m_z1[ch] = x;
return ( m_a0 * x ) + ( m_z1[ch] * m_a1 ) + ( m_z2[ch] * m_a2 ) +
( m_z3[ch] * m_a1 ) + ( m_z4[ch] * m_a0 );*/
}
private:
float m_sampleRate;
float m_wc4;
float m_k4;
float m_a, m_a0, m_a1, m_a2;
float m_b1, m_b2, m_b3, m_b4;
double m_wc4;
double m_k4;
double m_a, m_a0, m_a1, m_a2;
double m_b1, m_b2, m_b3, m_b4;
typedef float frame[CHANNELS];
typedef double frame[CHANNELS];
frame m_z1, m_z2, m_z3, m_z4;
frame m_y1, m_y2, m_y3, m_y4;
};
typedef LinkwitzRiley<2> StereoLinkwitzRiley;

2
include/Fader.h
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@@ -103,7 +103,7 @@ private:
float fRange = m_model->maxValue() - m_model->minValue();
float realVal = m_model->value() - m_model->minValue();
return height() - ( ( height() - ( *s_knob ).height() ) * ( realVal / fRange ) );
return height() - ( ( height() - m_knob->height() ) * ( realVal / fRange ) );
}
FloatModel * m_model;