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sdrangel/sdrbase/dsp/inthalfbandfiltereo1.h
2016-12-31 04:23:59 +01:00

602 lines
18 KiB
C++

///////////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2016 F4EXB //
// written by Edouard Griffiths //
// //
// Integer half-band FIR based interpolator and decimator //
// This is the even/odd double buffer variant. Really useful only when SIMD is //
// used //
// //
// 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 SDRBASE_DSP_INTHALFBANDFILTEREO_H_
#define SDRBASE_DSP_INTHALFBANDFILTEREO_H_
#include <stdint.h>
#include <cstdlib>
#include "dsp/dsptypes.h"
#include "dsp/hbfiltertraits.h"
#include "dsp/inthalfbandfiltereo1i.h"
#include "util/export.h"
template<uint32_t HBFilterOrder>
class SDRANGEL_API IntHalfbandFilterEO1 {
public:
IntHalfbandFilterEO1();
// 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
advancePointer();
// next state
m_state = 1;
// tell caller we don't have a new sample
return false;
default:
// save result
doFIR(sample);
// advance write-pointer
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// next state
m_state = 0;
// tell caller we consumed the sample
return true;
}
}
bool workDecimateCenter(int32_t *x, int32_t *y)
{
// insert sample into ring-buffer
storeSample(*x, *y);
switch(m_state)
{
case 0:
// advance write-pointer
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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
advancePointer();
// 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());
advancePointer();
storeSample((FixReal) sample2->real(), (FixReal) sample2->imag());
doFIR(sample2);
advancePointer();
}
void myDecimate(int32_t x1, int32_t y1, int32_t *x2, int32_t *y2)
{
storeSample(x1, y1);
advancePointer();
storeSample(*x2, *y2);
doFIR(x2, y2);
advancePointer();
}
void myInterpolate(Sample* sample1, Sample* sample2)
{
storeSample((FixReal) sample1->real(), (FixReal) sample1->imag());
doFIR(sample1);
advancePointer();
storeSample(0, 0);
doFIR(sample2);
advancePointer();
}
void myInterpolate(int32_t *x1, int32_t *y1, int32_t *x2, int32_t *y2)
{
storeSample(*x1, *y1);
doFIR(x1, y1);
advancePointer();
storeSample(0, 0);
doFIR(x2, y2);
advancePointer();
}
protected:
int32_t m_even[2][HBFIRFilterTraits<HBFilterOrder>::hbOrder]; // double buffer technique
int32_t m_odd[2][HBFIRFilterTraits<HBFilterOrder>::hbOrder]; // double buffer technique
int m_ptr;
int m_size;
int m_state;
void storeSample(const FixReal& sampleI, const FixReal& sampleQ)
{
if ((m_ptr % 2) == 0)
{
m_even[0][m_ptr/2] = sampleI;
m_even[1][m_ptr/2] = sampleQ;
m_even[0][m_ptr/2 + m_size] = sampleI;
m_even[1][m_ptr/2 + m_size] = sampleQ;
}
else
{
m_odd[0][m_ptr/2] = sampleI;
m_odd[1][m_ptr/2] = sampleQ;
m_odd[0][m_ptr/2 + m_size] = sampleI;
m_odd[1][m_ptr/2 + m_size] = sampleQ;
}
}
void storeSample(int32_t x, int32_t y)
{
if ((m_ptr % 2) == 0)
{
m_even[0][m_ptr/2] = x;
m_even[1][m_ptr/2] = y;
m_even[0][m_ptr/2 + m_size] = x;
m_even[1][m_ptr/2 + m_size] = y;
}
else
{
m_odd[0][m_ptr/2] = x;
m_odd[1][m_ptr/2] = y;
m_odd[0][m_ptr/2 + m_size] = x;
m_odd[1][m_ptr/2 + m_size] = y;
}
}
void advancePointer()
{
m_ptr = m_ptr + 1 < 2*m_size ? m_ptr + 1: 0;
}
int32_t rand(int32_t mod)
{
return (RAND_MAX/2 - std::rand()) % mod;
}
void doFIR(Sample* sample)
{
int32_t iAcc = 0;
int32_t qAcc = 0;
#ifdef USE_SSE4_1
IntHalfbandFilterEO1Intrisics<HBFilterOrder>::work(
m_ptr,
m_even,
m_odd,
iAcc,
qAcc
);
#else
int a = m_ptr/2 + m_size; // tip pointer
int b = m_ptr/2 + 1; // tail pointer
for (int i = 0; i < HBFIRFilterTraits<HBFilterOrder>::hbOrder / 4; i++)
{
if ((m_ptr % 2) == 0)
{
iAcc += (m_even[0][a] + m_even[0][b]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
qAcc += (m_even[1][a] + m_even[1][b]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
}
else
{
iAcc += (m_odd[0][a] + m_odd[0][b]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
qAcc += (m_odd[1][a] + m_odd[1][b]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
}
a -= 1;
b += 1;
}
#endif
if ((m_ptr % 2) == 0)
{
iAcc += ((int32_t)m_odd[0][m_ptr/2 + m_size/2]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
qAcc += ((int32_t)m_odd[1][m_ptr/2 + m_size/2]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
}
else
{
iAcc += ((int32_t)m_even[0][m_ptr/2 + m_size/2 + 1]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
qAcc += ((int32_t)m_even[1][m_ptr/2 + m_size/2 + 1]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
}
sample->setReal(iAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1);
sample->setImag(qAcc >> HBFIRFilterTraits<HBFilterOrder>::hbShift -1);
}
void doFIR(int32_t *x, int32_t *y)
{
int32_t iAcc = 0;
int32_t qAcc = 0;
#ifdef USE_SSE4_1
IntHalfbandFilterEO1Intrisics<HBFilterOrder>::work(
m_ptr,
m_even,
m_odd,
iAcc,
qAcc
);
#else
int a = m_ptr/2 + m_size; // tip pointer
int b = m_ptr/2 + 1; // tail pointer
for (int i = 0; i < HBFIRFilterTraits<HBFilterOrder>::hbOrder / 4; i++)
{
if ((m_ptr % 2) == 0)
{
iAcc += (m_even[0][a] + m_even[0][b]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
qAcc += (m_even[1][a] + m_even[1][b]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
}
else
{
iAcc += (m_odd[0][a] + m_odd[0][b]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
qAcc += (m_odd[1][a] + m_odd[1][b]) * HBFIRFilterTraits<HBFilterOrder>::hbCoeffs[i];
}
a -= 1;
b += 1;
}
#endif
if ((m_ptr % 2) == 0)
{
iAcc += ((int32_t)m_odd[0][m_ptr/2 + m_size/2]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
qAcc += ((int32_t)m_odd[1][m_ptr/2 + m_size/2]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
}
else
{
iAcc += ((int32_t)m_even[0][m_ptr/2 + m_size/2 + 1]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
qAcc += ((int32_t)m_even[1][m_ptr/2 + m_size/2 + 1]) << (HBFIRFilterTraits<HBFilterOrder>::hbShift - 1);
}
*x = iAcc >> (HBFIRFilterTraits<HBFilterOrder>::hbShift -1); // HB_SHIFT incorrect do not loose the gained bit
*y = qAcc >> (HBFIRFilterTraits<HBFilterOrder>::hbShift -1);
}
};
template<uint32_t HBFilterOrder>
IntHalfbandFilterEO1<HBFilterOrder>::IntHalfbandFilterEO1()
{
m_size = HBFIRFilterTraits<HBFilterOrder>::hbOrder/2;
for (int i = 0; i < 2*m_size; i++)
{
m_even[0][i] = 0;
m_even[1][i] = 0;
m_odd[0][i] = 0;
m_odd[1][i] = 0;
}
m_ptr = 0;
m_state = 0;
}
#endif /* SDRBASE_DSP_INTHALFBANDFILTEREO_H_ */