kopia lustrzana https://github.com/f4exb/sdrangel
146 wiersze
5.8 KiB
C++
146 wiersze
5.8 KiB
C++
///////////////////////////////////////////////////////////////////////////////////
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// Copyright (C) 2016 Edouard Griffiths, F4EXB. //
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// //
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// This program is free software; you can redistribute it and/or modify //
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// it under the terms of the GNU General Public License as published by //
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// the Free Software Foundation as version 3 of the License, or //
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// //
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// This program is distributed in the hope that it will be useful, //
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// but WITHOUT ANY WARRANTY; without even the implied warranty of //
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the //
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// GNU General Public License V3 for more details. //
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// //
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// You should have received a copy of the GNU General Public License //
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// along with this program. If not, see <http://www.gnu.org/licenses/>. //
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///////////////////////////////////////////////////////////////////////////////////
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#include "dsd_filters.h"
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namespace DSDplus
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{
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// DMR filter
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const float DSDFilters::xcoeffs[] =
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{ -0.0083649323f, -0.0265444850f, -0.0428141462f, -0.0537571943f,
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-0.0564141052f, -0.0489161045f, -0.0310068662f, -0.0043393881f,
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+0.0275375106f, +0.0595423283f, +0.0857543325f, +0.1003565948f,
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+0.0986944931f, +0.0782804830f, +0.0395670487f, -0.0136691535f,
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-0.0744390415f, -0.1331834575f, -0.1788967208f, -0.2005995448f,
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-0.1889627181f, -0.1378439993f, -0.0454976231f, +0.0847488694f,
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+0.2444859269f, +0.4209222342f, +0.5982295474f, +0.7593684540f,
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+0.8881539892f, +0.9712773915f, +0.9999999166f, +0.9712773915f,
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+0.8881539892f, +0.7593684540f, +0.5982295474f, +0.4209222342f,
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+0.2444859269f, +0.0847488694f, -0.0454976231f, -0.1378439993f,
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-0.1889627181f, -0.2005995448f, -0.1788967208f, -0.1331834575f,
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-0.0744390415f, -0.0136691535f, +0.0395670487f, +0.0782804830f,
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+0.0986944931f, +0.1003565948f, +0.0857543325f, +0.0595423283f,
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+0.0275375106f, -0.0043393881f, -0.0310068662f, -0.0489161045f,
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-0.0564141052f, -0.0537571943f, -0.0428141462f, -0.0265444850f,
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-0.0083649323f, };
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// NXDN filter
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const float DSDFilters::nxcoeffs[] =
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{ +0.031462429f, +0.031747267f, +0.030401148f, +0.027362877f, +0.022653298f,
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+0.016379869f, +0.008737200f, +0.000003302f, -0.009468531f,
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-0.019262057f, -0.028914291f, -0.037935027f, -0.045828927f,
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-0.052119261f, -0.056372283f, -0.058221106f, -0.057387924f,
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-0.053703443f, -0.047122444f, -0.037734535f, -0.025769308f,
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-0.011595336f, +0.004287292f, +0.021260954f, +0.038610717f,
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+0.055550276f, +0.071252765f, +0.084885375f, +0.095646450f,
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+0.102803611f, +0.105731303f, +0.103946126f, +0.097138329f,
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+0.085197939f, +0.068234131f, +0.046586711f, +0.020828821f,
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-0.008239664f, -0.039608255f, -0.072081234f, -0.104311776f,
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-0.134843790f, -0.162160200f, -0.184736015f, -0.201094346f,
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-0.209863285f, -0.209831516f, -0.200000470f, -0.179630919f,
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-0.148282051f, -0.105841323f, -0.052543664f, +0.011020985f,
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+0.083912428f, +0.164857408f, +0.252278939f, +0.344336996f,
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+0.438979335f, +0.534000832f, +0.627109358f, +0.715995947f,
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+0.798406824f, +0.872214756f, +0.935487176f, +0.986548646f,
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+1.024035395f, +1.046939951f, +1.054644241f, +1.046939951f,
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+1.024035395f, +0.986548646f, +0.935487176f, +0.872214756f,
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+0.798406824f, +0.715995947f, +0.627109358f, +0.534000832f,
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+0.438979335f, +0.344336996f, +0.252278939f, +0.164857408f,
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+0.083912428f, +0.011020985f, -0.052543664f, -0.105841323f,
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-0.148282051f, -0.179630919f, -0.200000470f, -0.209831516f,
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-0.209863285f, -0.201094346f, -0.184736015f, -0.162160200f,
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-0.134843790f, -0.104311776f, -0.072081234f, -0.039608255f,
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-0.008239664f, +0.020828821f, +0.046586711f, +0.068234131f,
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+0.085197939f, +0.097138329f, +0.103946126f, +0.105731303f,
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+0.102803611f, +0.095646450f, +0.084885375f, +0.071252765f,
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+0.055550276f, +0.038610717f, +0.021260954f, +0.004287292f,
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-0.011595336f, -0.025769308f, -0.037734535f, -0.047122444f,
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-0.053703443f, -0.057387924f, -0.058221106f, -0.056372283f,
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-0.052119261f, -0.045828927f, -0.037935027f, -0.028914291f,
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-0.019262057f, -0.009468531f, +0.000003302f, +0.008737200f,
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+0.016379869f, +0.022653298f, +0.027362877f, +0.030401148f,
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+0.031747267f, +0.031462429f, };
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DSDFilters::DSDFilters()
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{
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for (int i=0; i < NZEROS+1; i++) {
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xv[i] = 0.0f;
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}
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for (int i=0; i < NXZEROS+1; i++) {
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nxv[i] = 0.0f;
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}
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}
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DSDFilters::~DSDFilters()
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{
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}
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short DSDFilters::dmr_filter(short sample)
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{
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return dsd_input_filter(sample, 1);
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}
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short DSDFilters::nxdn_filter(short sample)
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{
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return dsd_input_filter(sample, 2);
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}
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short DSDFilters::dsd_input_filter(short sample, int mode)
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{
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float sum;
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int i;
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float gain;
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int zeros;
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float *v;
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const float *coeffs;
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switch (mode)
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{
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case 1:
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gain = ngain;
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v = xv;
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coeffs = xcoeffs;
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zeros = NZEROS;
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break;
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case 2:
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gain = nxgain;
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v = nxv;
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coeffs = nxcoeffs;
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zeros = NXZEROS;
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break;
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default:
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return sample;
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}
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for (i = 0; i < zeros; i++) {
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v[i] = v[i + 1];
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}
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v[zeros] = sample; // unfiltered sample in
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sum = 0.0f;
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for (i = 0; i <= zeros; i++) {
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sum += (coeffs[i] * v[i]);
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}
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return sum / ngain; // filtered sample out
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}
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} // namespace dsdplus
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