mirror of
https://github.com/f4exb/sdrangel.git
synced 2024-09-28 15:56:33 -04:00
Added new halfband FIR filter with even/odd and I/Q stride
This commit is contained in:
parent
a40f31ed4a
commit
bfe24df76e
@ -213,6 +213,7 @@ set(sdrbase_HEADERS
|
||||
sdrbase/dsp/inthalfbandfiltereo1i.h
|
||||
sdrbase/dsp/inthalfbandfiltereo2.h
|
||||
sdrbase/dsp/inthalfbandfiltereo2i.h
|
||||
sdrbase/dsp/inthalfbandfilterst.h
|
||||
sdrbase/dsp/kissfft.h
|
||||
sdrbase/dsp/kissengine.h
|
||||
sdrbase/dsp/lowpass.h
|
||||
|
530
sdrbase/dsp/inthalfbandfilterst.h
Normal file
530
sdrbase/dsp/inthalfbandfilterst.h
Normal file
@ -0,0 +1,530 @@
|
||||
///////////////////////////////////////////////////////////////////////////////////
|
||||
// Copyright (C) 2016 F4EXB //
|
||||
// written by Edouard Griffiths //
|
||||
// //
|
||||
// Integer half-band FIR based interpolator and decimator //
|
||||
// This is the double buffer variant //
|
||||
// //
|
||||
// This program is free software; you can redistribute it and/or modify //
|
||||
// it under the terms of the GNU General Public License as published by //
|
||||
// the Free Software Foundation as version 3 of the License, or //
|
||||
// //
|
||||
// This program is distributed in the hope that it will be useful, //
|
||||
// but WITHOUT ANY WARRANTY; without even the implied warranty of //
|
||||
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the //
|
||||
// GNU General Public License V3 for more details. //
|
||||
// //
|
||||
// You should have received a copy of the GNU General Public License //
|
||||
// along with this program. If not, see <http://www.gnu.org/licenses/>. //
|
||||
///////////////////////////////////////////////////////////////////////////////////
|
||||
|
||||
#ifndef INCLUDE_INTHALFBANDFILTER_ST_H
|
||||
#define INCLUDE_INTHALFBANDFILTER_ST_H
|
||||
|
||||
#include <stdint.h>
|
||||
#include "dsp/dsptypes.h"
|
||||
#include "dsp/hbfiltertraits.h"
|
||||
#include "util/export.h"
|
||||
|
||||
template<uint32_t HBFilterOrder>
|
||||
class SDRANGEL_API IntHalfbandFilterST {
|
||||
public:
|
||||
IntHalfbandFilterST();
|
||||
|
||||
// downsample by 2, return center part of original spectrum
|
||||
bool workDecimateCenter(Sample* sample)
|
||||
{
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) sample->real(), (FixReal) sample->imag());
|
||||
|
||||
switch(m_state)
|
||||
{
|
||||
case 0:
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// 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 + 1) % m_size;
|
||||
// next state
|
||||
m_state = 0;
|
||||
|
||||
// tell caller we have a new sample
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
// upsample by 2, return center part of original spectrum - double buffer variant
|
||||
bool workInterpolateCenter(Sample* sampleIn, Sample *SampleOut)
|
||||
{
|
||||
switch(m_state)
|
||||
{
|
||||
case 0:
|
||||
// insert sample into ring-buffer
|
||||
storeSample(0, 0);
|
||||
// save result
|
||||
doFIR(SampleOut);
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 1;
|
||||
// tell caller we didn't consume the sample
|
||||
return false;
|
||||
|
||||
default:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) sampleIn->real(), (FixReal) sampleIn->imag());
|
||||
// save result
|
||||
doFIR(SampleOut);
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 0;
|
||||
// tell caller we consumed the sample
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
bool workDecimateCenter(qint32 *x, qint32 *y)
|
||||
{
|
||||
// insert sample into ring-buffer
|
||||
storeSample(*x, *y);
|
||||
|
||||
switch(m_state)
|
||||
{
|
||||
case 0:
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// 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 + 1) % m_size;
|
||||
// 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
|
||||
storeSample((FixReal) -sample->imag(), (FixReal) sample->real());
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 1;
|
||||
// tell caller we don't have a new sample
|
||||
return false;
|
||||
|
||||
case 1:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) -sample->real(), (FixReal) -sample->imag());
|
||||
// save result
|
||||
doFIR(sample);
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 2;
|
||||
// tell caller we have a new sample
|
||||
return true;
|
||||
|
||||
case 2:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) sample->imag(), (FixReal) -sample->real());
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 3;
|
||||
// tell caller we don't have a new sample
|
||||
return false;
|
||||
|
||||
default:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) sample->real(), (FixReal) sample->imag());
|
||||
// save result
|
||||
doFIR(sample);
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 0;
|
||||
// tell caller we have a new sample
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
// upsample by 2, from lower half of original spectrum - double buffer variant
|
||||
bool workInterpolateLowerHalf(Sample* sampleIn, Sample *sampleOut)
|
||||
{
|
||||
Sample s;
|
||||
|
||||
switch(m_state)
|
||||
{
|
||||
case 0:
|
||||
// insert sample into ring-buffer
|
||||
storeSample(0, 0);
|
||||
|
||||
// save result
|
||||
doFIR(&s);
|
||||
sampleOut->setReal(s.imag());
|
||||
sampleOut->setImag(-s.real());
|
||||
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
// next state
|
||||
m_state = 1;
|
||||
|
||||
// tell caller we didn't consume the sample
|
||||
return false;
|
||||
|
||||
case 1:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) sampleIn->real(), (FixReal) sampleIn->imag());
|
||||
|
||||
// save result
|
||||
doFIR(&s);
|
||||
sampleOut->setReal(-s.real());
|
||||
sampleOut->setImag(-s.imag());
|
||||
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
// next state
|
||||
m_state = 2;
|
||||
|
||||
// tell caller we consumed the sample
|
||||
return true;
|
||||
|
||||
case 2:
|
||||
// insert sample into ring-buffer
|
||||
storeSample(0, 0);
|
||||
|
||||
// save result
|
||||
doFIR(&s);
|
||||
sampleOut->setReal(-s.imag());
|
||||
sampleOut->setImag(s.real());
|
||||
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
// next state
|
||||
m_state = 3;
|
||||
|
||||
// tell caller we didn't consume the sample
|
||||
return false;
|
||||
|
||||
default:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) sampleIn->real(), (FixReal) sampleIn->imag());
|
||||
|
||||
// save result
|
||||
doFIR(&s);
|
||||
sampleOut->setReal(s.real());
|
||||
sampleOut->setImag(s.imag());
|
||||
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
// next state
|
||||
m_state = 0;
|
||||
|
||||
// tell caller we consumed the 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
|
||||
storeSample((FixReal) sample->imag(), (FixReal) -sample->real());
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 1;
|
||||
// tell caller we don't have a new sample
|
||||
return false;
|
||||
|
||||
case 1:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) -sample->real(), (FixReal) -sample->imag());
|
||||
// save result
|
||||
doFIR(sample);
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 2;
|
||||
// tell caller we have a new sample
|
||||
return true;
|
||||
|
||||
case 2:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) -sample->imag(), (FixReal) sample->real());
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 3;
|
||||
// tell caller we don't have a new sample
|
||||
return false;
|
||||
|
||||
default:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) sample->real(), (FixReal) sample->imag());
|
||||
// save result
|
||||
doFIR(sample);
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
// next state
|
||||
m_state = 0;
|
||||
// tell caller we have a new sample
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
// upsample by 2, move original spectrum to upper half - double buffer variant
|
||||
bool workInterpolateUpperHalf(Sample* sampleIn, Sample *sampleOut)
|
||||
{
|
||||
Sample s;
|
||||
|
||||
switch(m_state)
|
||||
{
|
||||
case 0:
|
||||
// insert sample into ring-buffer
|
||||
storeSample(0, 0);
|
||||
|
||||
// save result
|
||||
doFIR(&s);
|
||||
sampleOut->setReal(-s.imag());
|
||||
sampleOut->setImag(s.real());
|
||||
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
// next state
|
||||
m_state = 1;
|
||||
|
||||
// tell caller we didn't consume the sample
|
||||
return false;
|
||||
|
||||
case 1:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) sampleIn->real(), (FixReal) sampleIn->imag());
|
||||
|
||||
// save result
|
||||
doFIR(&s);
|
||||
sampleOut->setReal(-s.real());
|
||||
sampleOut->setImag(-s.imag());
|
||||
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
// next state
|
||||
m_state = 2;
|
||||
|
||||
// tell caller we consumed the sample
|
||||
return true;
|
||||
|
||||
case 2:
|
||||
// insert sample into ring-buffer
|
||||
storeSample(0, 0);
|
||||
|
||||
// save result
|
||||
doFIR(&s);
|
||||
sampleOut->setReal(s.imag());
|
||||
sampleOut->setImag(-s.real());
|
||||
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
// next state
|
||||
m_state = 3;
|
||||
|
||||
// tell caller we didn't consume the sample
|
||||
return false;
|
||||
|
||||
default:
|
||||
// insert sample into ring-buffer
|
||||
storeSample((FixReal) sampleIn->real(), (FixReal) sampleIn->imag());
|
||||
|
||||
// save result
|
||||
doFIR(&s);
|
||||
sampleOut->setReal(s.real());
|
||||
sampleOut->setImag(s.imag());
|
||||
|
||||
// advance write-pointer
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
// next state
|
||||
m_state = 0;
|
||||
|
||||
// tell caller we consumed the sample
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
void myDecimate(const Sample* sample1, Sample* sample2)
|
||||
{
|
||||
storeSample((FixReal) sample1->real(), (FixReal) sample1->imag());
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
storeSample((FixReal) sample2->real(), (FixReal) sample2->imag());
|
||||
doFIR(sample2);
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
}
|
||||
|
||||
void myDecimate(qint32 x1, qint32 y1, qint32 *x2, qint32 *y2)
|
||||
{
|
||||
storeSample(x1, y1);
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
|
||||
storeSample(*x2, *y2);
|
||||
doFIR(x2, y2);
|
||||
m_ptr = (m_ptr + 1) % m_size;
|
||||
}
|
||||
|
||||
protected:
|
||||
qint32 m_samplesDB[2*HBFIRFilterTraits<HBFilterOrder>::hbOrder][2]; // double buffer technique with even/odd amnd I/Q stride
|
||||
int m_ptr;
|
||||
int m_size;
|
||||
int m_state;
|
||||
qint32 m_iEvenAcc;
|
||||
qint32 m_qEvenAcc;
|
||||
qint32 m_iOddAcc;
|
||||
qint32 m_qOddAcc;
|
||||
|
||||
|
||||
void storeSample(const FixReal& sampleI, const FixReal& sampleQ)
|
||||
{
|
||||
m_samplesDB[m_ptr][0] = sampleI;
|
||||
m_samplesDB[m_ptr][1] = sampleQ;
|
||||
m_samplesDB[m_ptr + m_size][0] = sampleI;
|
||||
m_samplesDB[m_ptr + m_size][1] = sampleQ;
|
||||
}
|
||||
|
||||
void storeSample(qint32 x, qint32 y)
|
||||
{
|
||||
m_samplesDB[m_ptr][0] = x;
|
||||
m_samplesDB[m_ptr][1] = y;
|
||||
m_samplesDB[m_ptr + m_size][0] = x;
|
||||
m_samplesDB[m_ptr + m_size][1] = y;
|
||||
}
|
||||
|
||||
void doFIR(Sample* sample)
|
||||
{
|
||||
int a = m_ptr + m_size; // tip pointer - odd
|
||||
int b = m_ptr + 1; // tail pointer - aven
|
||||
|
||||
// calculate on odd values
|
||||
|
||||
if ((m_ptr % 2) == 1)
|
||||
{
|
||||
m_iEvenAcc = 0;
|
||||
m_qEvenAcc = 0;
|
||||
m_iOddAcc = 0;
|
||||
m_qOddAcc = 0;
|
||||
|
||||
for (int i = 0; i < HBFIRFilterTraits<HBFilterOrder>::hbOrder / 4; i++)
|
||||
{
|
||||
m_iEvenAcc += (m_samplesDB[a-1][0] + m_samplesDB[b][0]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
|
||||
m_iOddAcc += (m_samplesDB[a][0] + m_samplesDB[b+1][0]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
|
||||
m_qEvenAcc += (m_samplesDB[a-1][1] + m_samplesDB[b][1]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
|
||||
m_qOddAcc += (m_samplesDB[a][1] + m_samplesDB[b+1][1]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
|
||||
a -= 2;
|
||||
b += 2;
|
||||
}
|
||||
|
||||
m_iEvenAcc += ((qint32)m_samplesDB[m_ptr + m_size/2][0]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
|
||||
m_qEvenAcc += ((qint32)m_samplesDB[m_ptr + m_size/2][1]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
|
||||
m_iOddAcc += ((qint32)m_samplesDB[m_ptr + m_size/2 + 1][0]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
|
||||
m_qOddAcc += ((qint32)m_samplesDB[m_ptr + m_size/2 + 1][1]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
|
||||
|
||||
sample->setReal(m_iEvenAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1);
|
||||
sample->setImag(m_qEvenAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1);
|
||||
}
|
||||
else
|
||||
{
|
||||
sample->setReal(m_iOddAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1);
|
||||
sample->setImag(m_qOddAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1);
|
||||
}
|
||||
}
|
||||
|
||||
void doFIR(qint32 *x, qint32 *y)
|
||||
{
|
||||
int a = m_ptr + m_size; // tip pointer - odd
|
||||
int b = m_ptr + 1; // tail pointer - aven
|
||||
|
||||
// calculate on odd values
|
||||
|
||||
if ((m_ptr % 2) == 1)
|
||||
{
|
||||
m_iEvenAcc = 0;
|
||||
m_qEvenAcc = 0;
|
||||
m_iOddAcc = 0;
|
||||
m_qOddAcc = 0;
|
||||
|
||||
for (int i = 0; i < HBFIRFilterTraits<HBFilterOrder>::hbOrder / 4; i++)
|
||||
{
|
||||
m_iEvenAcc += (m_samplesDB[a-1][0] + m_samplesDB[b][0]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
|
||||
m_iOddAcc += (m_samplesDB[a][0] + m_samplesDB[b+1][0]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
|
||||
m_qEvenAcc += (m_samplesDB[a-1][1] + m_samplesDB[b][1]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
|
||||
m_qOddAcc += (m_samplesDB[a][1] + m_samplesDB[b+1][1]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
|
||||
a -= 2;
|
||||
b += 2;
|
||||
}
|
||||
|
||||
m_iEvenAcc += ((qint32)m_samplesDB[m_ptr + m_size/2][0]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
|
||||
m_qEvenAcc += ((qint32)m_samplesDB[m_ptr + m_size/2][1]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
|
||||
m_iOddAcc += ((qint32)m_samplesDB[m_ptr + m_size/2 + 1][0]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
|
||||
m_qOddAcc += ((qint32)m_samplesDB[m_ptr + m_size/2 + 1][1]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
|
||||
|
||||
*x = m_iEvenAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1;
|
||||
*y = m_qEvenAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1;
|
||||
}
|
||||
else
|
||||
{
|
||||
*x = m_iOddAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1;
|
||||
*y = m_qOddAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1;
|
||||
}
|
||||
}
|
||||
};
|
||||
|
||||
template<uint32_t HBFilterOrder>
|
||||
IntHalfbandFilterST<HBFilterOrder>::IntHalfbandFilterST()
|
||||
{
|
||||
m_size = HBFIRFilterTraits<HBFilterOrder>::hbOrder;
|
||||
|
||||
for (int i = 0; i < m_size; i++)
|
||||
{
|
||||
m_samplesDB[i][0] = 0;
|
||||
m_samplesDB[i][1] = 0;
|
||||
}
|
||||
|
||||
m_ptr = 0;
|
||||
m_state = 0;
|
||||
m_iEvenAcc = 0;
|
||||
m_qEvenAcc = 0;
|
||||
m_iOddAcc = 0;
|
||||
m_qOddAcc = 0;
|
||||
}
|
||||
|
||||
#endif // INCLUDE_INTHALFBANDFILTER_DB_H
|
Loading…
Reference in New Issue
Block a user