mirror of
https://github.com/f4exb/sdrangel.git
synced 2025-10-30 20:40:20 -04:00
477 lines
14 KiB
C++
477 lines
14 KiB
C++
#ifndef INCLUDE_INTHALFBANDFILTER_H
|
|
#define INCLUDE_INTHALFBANDFILTER_H
|
|
|
|
#include <QtGlobal>
|
|
#include "dsp/dsptypes.h"
|
|
#include "util/export.h"
|
|
|
|
// uses Q1.14 format internally, input and output are S16
|
|
|
|
/*
|
|
* supported filter orders: 64, 48, 32
|
|
*/
|
|
#define HB_FILTERORDER 32
|
|
#define HB_SHIFT 14
|
|
|
|
class SDRANGEL_API IntHalfbandFilter {
|
|
public:
|
|
IntHalfbandFilter();
|
|
|
|
// downsample by 2, return center part of original spectrum
|
|
bool workDecimateCenter(Sample* sample)
|
|
{
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = sample->real();
|
|
m_samples[m_ptr][1] = sample->imag();
|
|
|
|
switch(m_state)
|
|
{
|
|
case 0:
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 1;
|
|
|
|
// tell caller we don't have a new sample
|
|
return false;
|
|
|
|
default:
|
|
// save result
|
|
doFIR(sample);
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 0;
|
|
|
|
// tell caller we have a new sample
|
|
return true;
|
|
}
|
|
}
|
|
|
|
bool workDecimateCenter(qint32 *x, qint32 *y)
|
|
{
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = *x;
|
|
m_samples[m_ptr][1] = *y;
|
|
|
|
switch(m_state)
|
|
{
|
|
case 0:
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 1;
|
|
|
|
// tell caller we don't have a new sample
|
|
return false;
|
|
|
|
default:
|
|
// save result
|
|
doFIR(x, y);
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 0;
|
|
|
|
// tell caller we have a new sample
|
|
return true;
|
|
}
|
|
}
|
|
|
|
// downsample by 2, return edges of spectrum rotated into center
|
|
bool workDecimateFullRotate(Sample* sample)
|
|
{
|
|
switch(m_state)
|
|
{
|
|
case 0:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = sample->real();
|
|
m_samples[m_ptr][1] = sample->imag();
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 1;
|
|
|
|
// tell caller we don't have a new sample
|
|
return false;
|
|
|
|
default:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = -sample->real();
|
|
m_samples[m_ptr][1] = sample->imag();
|
|
|
|
// save result
|
|
doFIR(sample);
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 0;
|
|
|
|
// tell caller we have a new sample
|
|
return true;
|
|
}
|
|
}
|
|
|
|
// downsample by 2, return lower half of original spectrum
|
|
bool workDecimateLowerHalf(Sample* sample)
|
|
{
|
|
switch(m_state)
|
|
{
|
|
case 0:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = -sample->imag();
|
|
m_samples[m_ptr][1] = sample->real();
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 1;
|
|
|
|
// tell caller we don't have a new sample
|
|
return false;
|
|
|
|
case 1:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = -sample->real();
|
|
m_samples[m_ptr][1] = -sample->imag();
|
|
|
|
// save result
|
|
doFIR(sample);
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 2;
|
|
|
|
// tell caller we have a new sample
|
|
return true;
|
|
|
|
case 2:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = sample->imag();
|
|
m_samples[m_ptr][1] = -sample->real();
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 3;
|
|
|
|
// tell caller we don't have a new sample
|
|
return false;
|
|
|
|
default:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = sample->real();
|
|
m_samples[m_ptr][1] = sample->imag();
|
|
|
|
// save result
|
|
doFIR(sample);
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 0;
|
|
|
|
// tell caller we have a new sample
|
|
return true;
|
|
}
|
|
}
|
|
|
|
// downsample by 2, return upper half of original spectrum
|
|
bool workDecimateUpperHalf(Sample* sample)
|
|
{
|
|
switch(m_state)
|
|
{
|
|
case 0:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = sample->imag();
|
|
m_samples[m_ptr][1] = -sample->real();
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 1;
|
|
|
|
// tell caller we don't have a new sample
|
|
return false;
|
|
|
|
case 1:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = -sample->real();
|
|
m_samples[m_ptr][1] = -sample->imag();
|
|
|
|
// save result
|
|
doFIR(sample);
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 2;
|
|
|
|
// tell caller we have a new sample
|
|
return true;
|
|
|
|
case 2:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = -sample->imag();
|
|
m_samples[m_ptr][1] = sample->real();
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 3;
|
|
|
|
// tell caller we don't have a new sample
|
|
return false;
|
|
|
|
default:
|
|
// insert sample into ring-buffer
|
|
m_samples[m_ptr][0] = sample->real();
|
|
m_samples[m_ptr][1] = sample->imag();
|
|
|
|
// save result
|
|
doFIR(sample);
|
|
|
|
// advance write-pointer
|
|
m_ptr = (m_ptr + HB_FILTERORDER) % (HB_FILTERORDER + 1);
|
|
|
|
// next state
|
|
m_state = 0;
|
|
|
|
// tell caller we have a new sample
|
|
return true;
|
|
}
|
|
}
|
|
|
|
void myDecimate(const Sample* sample1, Sample* sample2)
|
|
{
|
|
static const qint16 mod33[38] = { 31,32,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,
|
|
20,21,22,23,24,25,26,27,28,29,30,31,32,0,1,2};
|
|
|
|
m_samples[m_ptr][0] = sample1->real();
|
|
m_samples[m_ptr][1] = sample1->imag();
|
|
m_ptr = mod33[m_ptr + 2 - 1];
|
|
|
|
m_samples[m_ptr][0] = sample2->real();
|
|
m_samples[m_ptr][1] = sample2->imag();
|
|
|
|
doFIR(sample2);
|
|
|
|
m_ptr = mod33[m_ptr + 2 - 1];
|
|
}
|
|
|
|
void myDecimate(qint32 x1, qint32 y1, qint32 *x2, qint32 *y2)
|
|
{
|
|
static const qint16 mod33[38] = { 31,32,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,
|
|
20,21,22,23,24,25,26,27,28,29,30,31,32,0,1,2};
|
|
|
|
m_samples[m_ptr][0] = x1;
|
|
m_samples[m_ptr][1] = y1;
|
|
m_ptr = mod33[m_ptr + 2 - 1];
|
|
|
|
m_samples[m_ptr][0] = *x2;
|
|
m_samples[m_ptr][1] = *y2;
|
|
|
|
doFIR(x2, y2);
|
|
|
|
m_ptr = mod33[m_ptr + 2 - 1];
|
|
}
|
|
|
|
protected:
|
|
qint32 m_samples[HB_FILTERORDER + 1][2]; // Valgrind optim (from qint16)
|
|
qint16 m_ptr;
|
|
int m_state;
|
|
|
|
void doFIR(Sample* sample)
|
|
{
|
|
// coefficents
|
|
|
|
#if HB_FILTERORDER == 64
|
|
static const qint32 COEFF[16] = {
|
|
-0.001114417441601693505720538368564120901 * (1 << HB_SHIFT),
|
|
0.001268007827185253051302527005361753254 * (1 << HB_SHIFT),
|
|
-0.001959831378850490895410230152151598304 * (1 << HB_SHIFT),
|
|
0.002878308307661380308073439948657323839 * (1 << HB_SHIFT),
|
|
-0.004071361818258721100571850826099762344 * (1 << HB_SHIFT),
|
|
0.005597288494657440618973431867289036745 * (1 << HB_SHIFT),
|
|
-0.007532345003308904551886371336877346039 * (1 << HB_SHIFT),
|
|
0.009980346844667375288961963519795972388 * (1 << HB_SHIFT),
|
|
-0.013092614174300500062830820979797863401 * (1 << HB_SHIFT),
|
|
0.01710934914871829748417297878404497169 * (1 << HB_SHIFT),
|
|
-0.022443558692997273018576720460259821266 * (1 << HB_SHIFT),
|
|
0.029875811511593811098386197500076377764 * (1 << HB_SHIFT),
|
|
-0.041086352085710403647667021687084343284 * (1 << HB_SHIFT),
|
|
0.060465467462665789533104998554335907102 * (1 << HB_SHIFT),
|
|
-0.104159517495977321788203084906854201108 * (1 << HB_SHIFT),
|
|
0.317657589850154464805598308885237202048 * (1 << HB_SHIFT),
|
|
};
|
|
#elif HB_FILTERORDER == 48
|
|
static const qint32 COEFF[12] = {
|
|
-0.004102576237611492253332112767338912818 * (1 << HB_SHIFT),
|
|
0.003950551047979387886410762575906119309 * (1 << HB_SHIFT),
|
|
-0.005807875789391703583164350277456833282 * (1 << HB_SHIFT),
|
|
0.00823497890520805998770814682075069868 * (1 << HB_SHIFT),
|
|
-0.011372226513199541059195851744334504474 * (1 << HB_SHIFT),
|
|
0.015471557140973646315984524335362948477 * (1 << HB_SHIFT),
|
|
-0.020944996398689276484450516591095947661 * (1 << HB_SHIFT),
|
|
0.028568078132034283034279553703527199104 * (1 << HB_SHIFT),
|
|
-0.040015143905614086738964374490024056286 * (1 << HB_SHIFT),
|
|
0.059669519431831075095828964549582451582 * (1 << HB_SHIFT),
|
|
-0.103669138691865420076609893840213771909 * (1 << HB_SHIFT),
|
|
0.317491986549921390015072120149852707982 * (1 << HB_SHIFT)
|
|
};
|
|
#elif HB_FILTERORDER == 32
|
|
static const qint16 mod33[38] = { 31,32,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,
|
|
20,21,22,23,24,25,26,27,28,29,30,31,32,0,1,2} ;
|
|
static const qint32 COEFF[8] = {
|
|
(qint32)(-0.015956912844043127236437484839370881673 * (1 << HB_SHIFT)),
|
|
(qint32)( 0.013023031678944928940522274274371739011 * (1 << HB_SHIFT)),
|
|
(qint32)(-0.01866942273717486777684371190844103694 * (1 << HB_SHIFT)),
|
|
(qint32)( 0.026550887571157304190005987720724078827 * (1 << HB_SHIFT)),
|
|
(qint32)(-0.038350314277854319344740474662103224546 * (1 << HB_SHIFT)),
|
|
(qint32)( 0.058429248652825838128421764849917963147 * (1 << HB_SHIFT)),
|
|
(qint32)(-0.102889802028955756885153505209018476307 * (1 << HB_SHIFT)),
|
|
(qint32)( 0.317237706405931241260276465254719369113 * (1 << HB_SHIFT))
|
|
};
|
|
#else
|
|
#error unsupported filter order
|
|
#endif
|
|
|
|
|
|
// init read-pointer
|
|
int a = mod33[m_ptr + 2 + 1]; // 0 + 1
|
|
int b = mod33[m_ptr + 2 - 2]; //-1 - 1
|
|
|
|
// go through samples in buffer
|
|
qint32 iAcc = 0;
|
|
qint32 qAcc = 0;
|
|
|
|
for (int i = 0; i < HB_FILTERORDER / 4; i++)
|
|
{
|
|
// do multiply-accumulate
|
|
//qint32 iTmp = m_samples[a][0] + m_samples[b][0]; // Valgrind optim
|
|
//qint32 qTmp = m_samples[a][1] + m_samples[b][1]; // Valgrind optim
|
|
iAcc += (m_samples[a][0] + m_samples[b][0]) * COEFF[i];
|
|
qAcc += (m_samples[a][1] + m_samples[b][1]) * COEFF[i];
|
|
|
|
// update read-pointer
|
|
a = mod33[a + 2 + 2];
|
|
b = mod33[b + 2 - 2];
|
|
}
|
|
|
|
a = mod33[a + 2 - 1];
|
|
|
|
iAcc += ((qint32)m_samples[a][0] + 1) << (HB_SHIFT - 1);
|
|
qAcc += ((qint32)m_samples[a][1] + 1) << (HB_SHIFT - 1);
|
|
|
|
sample->setReal(iAcc >> HB_SHIFT);
|
|
sample->setImag(qAcc >> HB_SHIFT);
|
|
}
|
|
|
|
void doFIR(qint32 *x, qint32 *y)
|
|
{
|
|
// coefficents
|
|
|
|
#if HB_FILTERORDER == 64
|
|
static const qint32 COEFF[16] = {
|
|
-0.001114417441601693505720538368564120901 * (1 << HB_SHIFT),
|
|
0.001268007827185253051302527005361753254 * (1 << HB_SHIFT),
|
|
-0.001959831378850490895410230152151598304 * (1 << HB_SHIFT),
|
|
0.002878308307661380308073439948657323839 * (1 << HB_SHIFT),
|
|
-0.004071361818258721100571850826099762344 * (1 << HB_SHIFT),
|
|
0.005597288494657440618973431867289036745 * (1 << HB_SHIFT),
|
|
-0.007532345003308904551886371336877346039 * (1 << HB_SHIFT),
|
|
0.009980346844667375288961963519795972388 * (1 << HB_SHIFT),
|
|
-0.013092614174300500062830820979797863401 * (1 << HB_SHIFT),
|
|
0.01710934914871829748417297878404497169 * (1 << HB_SHIFT),
|
|
-0.022443558692997273018576720460259821266 * (1 << HB_SHIFT),
|
|
0.029875811511593811098386197500076377764 * (1 << HB_SHIFT),
|
|
-0.041086352085710403647667021687084343284 * (1 << HB_SHIFT),
|
|
0.060465467462665789533104998554335907102 * (1 << HB_SHIFT),
|
|
-0.104159517495977321788203084906854201108 * (1 << HB_SHIFT),
|
|
0.317657589850154464805598308885237202048 * (1 << HB_SHIFT),
|
|
};
|
|
#elif HB_FILTERORDER == 48
|
|
static const qint32 COEFF[12] = {
|
|
-0.004102576237611492253332112767338912818 * (1 << HB_SHIFT),
|
|
0.003950551047979387886410762575906119309 * (1 << HB_SHIFT),
|
|
-0.005807875789391703583164350277456833282 * (1 << HB_SHIFT),
|
|
0.00823497890520805998770814682075069868 * (1 << HB_SHIFT),
|
|
-0.011372226513199541059195851744334504474 * (1 << HB_SHIFT),
|
|
0.015471557140973646315984524335362948477 * (1 << HB_SHIFT),
|
|
-0.020944996398689276484450516591095947661 * (1 << HB_SHIFT),
|
|
0.028568078132034283034279553703527199104 * (1 << HB_SHIFT),
|
|
-0.040015143905614086738964374490024056286 * (1 << HB_SHIFT),
|
|
0.059669519431831075095828964549582451582 * (1 << HB_SHIFT),
|
|
-0.103669138691865420076609893840213771909 * (1 << HB_SHIFT),
|
|
0.317491986549921390015072120149852707982 * (1 << HB_SHIFT)
|
|
};
|
|
#elif HB_FILTERORDER == 32
|
|
static const int mod33[38] = { 31,32,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,
|
|
20,21,22,23,24,25,26,27,28,29,30,31,32,0,1,2} ;
|
|
static const qint32 COEFF[8] = {
|
|
(qint32)(-0.015956912844043127236437484839370881673 * (1 << HB_SHIFT)),
|
|
(qint32)( 0.013023031678944928940522274274371739011 * (1 << HB_SHIFT)),
|
|
(qint32)(-0.01866942273717486777684371190844103694 * (1 << HB_SHIFT)),
|
|
(qint32)( 0.026550887571157304190005987720724078827 * (1 << HB_SHIFT)),
|
|
(qint32)(-0.038350314277854319344740474662103224546 * (1 << HB_SHIFT)),
|
|
(qint32)( 0.058429248652825838128421764849917963147 * (1 << HB_SHIFT)),
|
|
(qint32)(-0.102889802028955756885153505209018476307 * (1 << HB_SHIFT)),
|
|
(qint32)( 0.317237706405931241260276465254719369113 * (1 << HB_SHIFT))
|
|
};
|
|
#else
|
|
#error unsupported filter order
|
|
#endif
|
|
|
|
|
|
// init read-pointer
|
|
int a = mod33[m_ptr + 2 + 1]; // 0 + 1
|
|
int b = mod33[m_ptr + 2 - 2]; //-1 - 1
|
|
|
|
// go through samples in buffer
|
|
qint32 iAcc = 0;
|
|
qint32 qAcc = 0;
|
|
|
|
for (int i = 0; i < HB_FILTERORDER / 4; i++)
|
|
{
|
|
// do multiply-accumulate
|
|
//qint32 iTmp = m_samples[a][0] + m_samples[b][0]; // Valgrind optim
|
|
//qint32 qTmp = m_samples[a][1] + m_samples[b][1]; // Valgrind optim
|
|
iAcc += (m_samples[a][0] + m_samples[b][0]) * COEFF[i];
|
|
qAcc += (m_samples[a][1] + m_samples[b][1]) * COEFF[i];
|
|
|
|
// update read-pointer
|
|
a = mod33[a + 2 + 2];
|
|
b = mod33[b + 2 - 2];
|
|
}
|
|
|
|
a = mod33[a + 2 - 1];
|
|
|
|
iAcc += ((qint32)m_samples[a][0] + 1) << (HB_SHIFT - 1);
|
|
qAcc += ((qint32)m_samples[a][1] + 1) << (HB_SHIFT - 1);
|
|
|
|
*x = iAcc >> (HB_SHIFT -1); // HB_SHIFT incorrect do not loose the gained bit
|
|
*y = qAcc >> (HB_SHIFT -1);
|
|
}
|
|
|
|
};
|
|
|
|
#endif // INCLUDE_INTHALFBANDFILTER_H
|