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-rw-r--r--lib/decoding/openbts/AmrCoder.cpp1891
1 files changed, 1891 insertions, 0 deletions
diff --git a/lib/decoding/openbts/AmrCoder.cpp b/lib/decoding/openbts/AmrCoder.cpp
new file mode 100644
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+++ b/lib/decoding/openbts/AmrCoder.cpp
@@ -0,0 +1,1891 @@
+/*
+ * Copyright 2013, 2014 Range Networks, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * This use of this software may be subject to additional restrictions.
+ * See the LEGAL file in the main directory for details.
+ */
+
+
+#include "BitVector.h"
+#include "AmrCoder.h"
+#include <iostream>
+#include <stdio.h>
+#include <sstream>
+
+using namespace std;
+
+
+
+ViterbiTCH_AFS12_2::ViterbiTCH_AFS12_2()
+{
+ assert(mDeferral < 32);
+ mCoeffs[0] = 0x019;
+ mCoeffsFB[0] = 0x019;
+ mCoeffs[1] = 0x01b;
+ mCoeffsFB[1] = 0x019;
+ for (unsigned i = 0; i < mIRate; i++) {
+ computeStateTables(i);
+ }
+ computeGeneratorTable();
+}
+
+
+//void BitVector::encode(const ViterbiTCH_AFS12_2& coder, BitVector& target) const
+void ViterbiTCH_AFS12_2::encode(const BitVector& in, BitVector& target) const
+{
+ assert(in.size() == 250);
+ assert(target.size() == 508);
+ const char *u = in.begin();
+ char *C = target.begin();
+ const unsigned H = 4;
+ BitVector r(254+H);
+ for (int k = -H; k <= -1; k++) r[k+H] = 0;
+ for (unsigned k = 0; k <= 249; k++) {
+ r[k+H] = u[k] ^ r[k-3+H] ^ r[k-4+H];
+ C[2*k] = u[k];
+ C[2*k+1] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ }
+ // termination
+ for (unsigned k = 250; k <= 253; k++) {
+ r[k+H] = 0;
+ C[2*k] = r[k-3+H] ^ r[k-4+H];
+ C[2*k+1] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ }
+}
+
+
+
+//void BitVector::encode(const ViterbiTCH_AFS10_2& coder, BitVector& target)
+void ViterbiTCH_AFS10_2::encode(const BitVector& in, BitVector& target) const
+{
+ assert(in.size() == 210);
+ assert(target.size() == 642);
+ const char *u = in.begin();
+ char *C = target.begin();
+ const unsigned H = 4;
+ BitVector r(214+H);
+ for (int k = -H; k <= -1; k++) r[k+H] = 0;
+ for (unsigned k = 0; k <= 209; k++) {
+ r[k+H] = u[k] ^ r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[3*k] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[3*k+1] = r[k+H] ^ r[k-2+H] ^ r[k-4+H];
+ C[3*k+2] = u[k];
+ }
+ // termination
+ for (unsigned k = 210; k <= 213; k++) {
+ r[k+H] = 0;
+ C[3*k] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[3*k+1] = r[k+H] ^ r[k-2+H] ^ r[k-4+H];
+ C[3*k+2] = r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ }
+}
+
+
+
+//void BitVector::encode(const ViterbiTCH_AFS7_95& coder, BitVector& target)
+void ViterbiTCH_AFS7_95::encode(const BitVector& in, BitVector& target) const
+{
+ assert(in.size() == 165);
+ assert(target.size() == 513);
+ const char *u = in.begin();
+ char *C = target.begin();
+ const unsigned H = 6;
+ BitVector r(171+H);
+ for (int k = -H; k <= -1; k++) r[k+H] = 0;
+ for (unsigned k = 0; k <= 164; k++) {
+ r[k+H] = u[k] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-5+H] ^ r[k-6+H];
+ C[3*k] = u[k];
+ C[3*k+1] = r[k+H] ^ r[k-1+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[3*k+2] = r[k+H] ^ r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H] ^ r[k-6+H];
+ }
+ // termination
+ for (unsigned k = 165; k <= 170; k++) {
+ r[k+H] = 0;
+ C[3*k] = r[k-2+H] ^ r[k-3+H] ^ r[k-5+H] ^ r[k-6+H];
+ C[3*k+1] = r[k+H] ^ r[k-1+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[3*k+2] = r[k+H] ^ r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H] ^ r[k-6+H];
+ }
+}
+
+
+
+void ViterbiTCH_AFS7_4::encode(const BitVector& in, BitVector& target) const
+{
+ assert(in.size() == 154);
+ assert(target.size() == 474);
+ const char *u = in.begin();
+ char *C = target.begin();
+ const unsigned H = 4;
+ BitVector r(158+H);
+ for (int k = -H; k <= -1; k++) r[k+H] = 0;
+ for (unsigned k = 0; k <= 153; k++) {
+ r[k+H] = u[k] ^ r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[3*k] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[3*k+1] = r[k+H] ^ r[k-2+H] ^ r[k-4+H];
+ C[3*k+2] = u[k];
+ }
+ // termination
+ for (unsigned k = 154; k <= 157; k++) {
+ r[k+H] = 0;
+ C[3*k] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[3*k+1] = r[k+H] ^ r[k-2+H] ^ r[k-4+H];
+ C[3*k+2] = r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ }
+}
+
+
+
+void ViterbiTCH_AFS6_7::encode(const BitVector& in, BitVector& target) const
+{
+ assert(in.size() == 140);
+ assert(target.size() == 576);
+ const char *u = in.begin();
+ char *C = target.begin();
+ const unsigned H = 4;
+ BitVector r(144+H);
+ for (int k = -H; k <= -1; k++) r[k+H] = 0;
+ for (unsigned k = 0; k <= 139; k++) {
+ r[k+H] = u[k] ^ r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[4*k] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[4*k+1] = r[k+H] ^ r[k-2+H] ^ r[k-4+H];
+ C[4*k+2] = u[k];
+ C[4*k+3] = u[k];
+ }
+ // termination
+ for (unsigned k = 140; k <= 143; k++) {
+ r[k+H] = 0;
+ C[4*k] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[4*k+1] = r[k+H] ^ r[k-2+H] ^ r[k-4+H];
+ C[4*k+2] = r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[4*k+3] = r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ }
+}
+
+
+
+void ViterbiTCH_AFS5_9::encode(const BitVector& in, BitVector& target) const
+{
+ assert(in.size() == 124);
+ assert(target.size() == 520);
+ const char *u = in.begin();
+ char *C = target.begin();
+ const unsigned H = 6;
+ BitVector r(130+H);
+ for (int k = -H; k <= -1; k++) r[k+H] = 0;
+ for (unsigned k = 0; k <= 123; k++) {
+ r[k+H] = u[k] ^ r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[4*k] = r[k+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-5+H] ^ r[k-6+H];
+ C[4*k+1] = r[k+H] ^ r[k-1+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[4*k+2] = u[k];
+ C[4*k+3] = u[k];
+ }
+ // termination
+ for (unsigned k = 124; k <= 129; k++) {
+ r[k+H] = 0;
+ C[4*k] = r[k+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-5+H] ^ r[k-6+H];
+ C[4*k+1] = r[k+H] ^ r[k-1+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[4*k+2] = r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[4*k+3] = r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H] ^ r[k-6+H];
+ }
+}
+
+
+
+void ViterbiTCH_AFS5_15::encode(const BitVector& in, BitVector& target) const
+{
+ assert(in.size() == 109);
+ assert(target.size() == 565);
+ const char *u = in.begin();
+ char *C = target.begin();
+ const unsigned H = 4;
+ BitVector r(113+H);
+ for (int k = -H; k <= -1; k++) r[k+H] = 0;
+ for (unsigned k = 0; k <= 108; k++) {
+ r[k+H] = u[k] ^ r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[5*k] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[5*k+1] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[5*k+2] = r[k+H] ^ r[k-2+H] ^ r[k-4+H];
+ C[5*k+3] = u[k];
+ C[5*k+4] = u[k];
+ }
+ // termination
+ for (unsigned k = 109; k <= 112; k++) {
+ r[k+H] = 0;
+ C[5*k] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[5*k+1] = r[k+H] ^ r[k-1+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[5*k+2] = r[k+H] ^ r[k-2+H] ^ r[k-4+H];
+ C[5*k+3] = r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ C[5*k+4] = r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H];
+ }
+}
+
+
+
+void ViterbiTCH_AFS4_75::encode(const BitVector& in, BitVector& target) const
+{
+ assert(in.size() == 101);
+ assert(target.size() == 535);
+ const char *u = in.begin();
+ char *C = target.begin();
+ const unsigned H = 6;
+ BitVector r(107+H);
+ for (int k = -H; k <= -1; k++) r[k+H] = 0;
+ for (unsigned k = 0; k <= 100; k++) {
+ r[k+H] = u[k] ^ r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[5*k] = r[k+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-5+H] ^ r[k-6+H];
+ C[5*k+1] = r[k+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-5+H] ^ r[k-6+H];
+ C[5*k+2] = r[k+H] ^ r[k-1+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[5*k+3] = u[k];
+ C[5*k+4] = u[k];
+ }
+ // termination
+ for (unsigned k = 101; k <= 106; k++) {
+ r[k+H] = 0;
+ C[5*k] = r[k+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-5+H] ^ r[k-6+H];
+ C[5*k+1] = r[k+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-5+H] ^ r[k-6+H];
+ C[5*k+2] = r[k+H] ^ r[k-1+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[5*k+3] = r[k+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H] ^ r[k-6+H];
+ C[5*k+4] = r[k-1+H] ^ r[k-2+H] ^ r[k-3+H] ^ r[k-4+H] ^ r[k-6+H];
+ }
+}
+
+
+void ViterbiTCH_AFS12_2::initializeStates()
+{
+ for (unsigned i=0; i<mIStates; i++) vitClear(mSurvivors[i]);
+ for (unsigned i=0; i<mNumCands; i++) vitClear(mCandidates[i]);
+}
+
+
+
+void ViterbiTCH_AFS12_2::computeStateTables(unsigned g)
+{
+ assert(g<mIRate);
+ for (unsigned state=0; state<mIStates; state++) {
+ for (unsigned in = 0; in <= 1; in++) {
+ uint32_t inputVal = (state<<1) | in;
+ mStateTable[g][inputVal] = applyPoly(inputVal, mCoeffs[g] ^ mCoeffsFB[g], mOrder+1) ^ in;
+ }
+ }
+}
+
+void ViterbiTCH_AFS12_2::computeGeneratorTable()
+{
+ for (unsigned index=0; index<mIStates*2; index++) {
+ uint32_t t = 0;
+ for (unsigned i = 0; i < mIRate; i++) {
+ t = (t << 1) | mStateTable[i][index];
+ }
+ mGeneratorTable[index] = t;
+ }
+}
+
+
+
+
+
+
+void ViterbiTCH_AFS12_2::branchCandidates()
+{
+ // Branch to generate new input states.
+ const vCand *sp = mSurvivors;
+ for (unsigned cand=0; cand<mNumCands; cand+=2) {
+ uint32_t oStateShifted = (sp->oState) << mIRate;
+ for (unsigned in = 0; in <= 1; in++) {
+ mCandidates[cand+in].iState = ((sp->iState) << 1) | in;
+ mCandidates[cand+in].cost = sp->cost;
+ uint32_t outputs = oStateShifted;
+ for (unsigned out = 0; out < mIRate; out++) {
+ char feedback = applyPoly(sp->rState[out], mCoeffsFB[out] ^ 1, mOrder+1);
+ char rState = (((sp->rState[out]) ^ feedback) << 1) | in;
+ mCandidates[cand+in].rState[out] = rState;
+ outputs |= (mGeneratorTable[rState & mCMask] & (1 << (mIRate - out - 1)));
+ }
+ mCandidates[cand+in].oState = outputs;
+ }
+ sp++;
+ }
+}
+
+
+void ViterbiTCH_AFS12_2::getSoftCostMetrics(const uint32_t inSample, const float *matchCost, const float *mismatchCost)
+{
+ const float *cTab[2] = {matchCost,mismatchCost};
+ for (unsigned i=0; i<mNumCands; i++) {
+ vCand& thisCand = mCandidates[i];
+ const unsigned mismatched = inSample ^ (thisCand.oState);
+ for (unsigned i = 0; i < mIRate; i++) {
+ thisCand.cost += cTab[(mismatched>>i)&0x01][mIRate-i-1];
+ }
+ }
+}
+
+
+void ViterbiTCH_AFS12_2::pruneCandidates()
+{
+ const vCand* c1 = mCandidates; // 0-prefix
+ const vCand* c2 = mCandidates + mIStates; // 1-prefix
+ for (unsigned i=0; i<mIStates; i++) {
+ if (c1[i].cost < c2[i].cost) mSurvivors[i] = c1[i];
+ else mSurvivors[i] = c2[i];
+ }
+}
+
+
+const ViterbiTCH_AFS12_2::vCand& ViterbiTCH_AFS12_2::minCost() const
+{
+ int minIndex = 0;
+ float minCost = mSurvivors[0].cost;
+ for (unsigned i=1; i<mIStates; i++) {
+ const float thisCost = mSurvivors[i].cost;
+ if (thisCost>=minCost) continue;
+ minCost = thisCost;
+ minIndex=i;
+ }
+ return mSurvivors[minIndex];
+}
+
+
+const ViterbiTCH_AFS12_2::vCand& ViterbiTCH_AFS12_2::step(uint32_t inSample, const float *probs, const float *iprobs)
+{
+ branchCandidates();
+ getSoftCostMetrics(inSample,probs,iprobs);
+ pruneCandidates();
+ return minCost();
+}
+
+
+
+void ViterbiTCH_AFS12_2::decode(const SoftVector &in, BitVector& target)
+{
+ ViterbiTCH_AFS12_2 &decoder = *this;
+ const size_t sz = in.size() - 8;
+ const unsigned deferral = decoder.deferral();
+ const size_t ctsz = sz + deferral*decoder.iRate();
+ assert(sz == decoder.iRate()*target.size());
+
+ // Build a "history" array where each element contains the full history.
+ uint32_t history[ctsz];
+ {
+ BitVector bits = in.sliced();
+ uint32_t accum = 0;
+ for (size_t i=0; i<sz; i++) {
+ accum = (accum<<1) | bits.bit(i);
+ history[i] = accum;
+ }
+ // Repeat last bit at the end.
+ for (size_t i=sz; i<ctsz; i++) {
+ accum = (accum<<1) | (accum & 0x01);
+ history[i] = accum;
+ }
+ }
+
+ // Precompute metric tables.
+ float matchCostTable[ctsz];
+ float mismatchCostTable[ctsz];
+ {
+ const float *dp = in.begin();
+ for (size_t i=0; i<sz; i++) {
+ // pVal is the probability that a bit is correct.
+ // ipVal is the probability that a bit is incorrect.
+ float pVal = dp[i];
+ if (pVal>0.5F) pVal = 1.0F-pVal;
+ float ipVal = 1.0F-pVal;
+ // This is a cheap approximation to an ideal cost function.
+ if (pVal<0.01F) pVal = 0.01;
+ if (ipVal<0.01F) ipVal = 0.01;
+ matchCostTable[i] = 0.25F/ipVal;
+ mismatchCostTable[i] = 0.25F/pVal;
+ }
+
+ // pad end of table with unknowns
+ for (size_t i=sz; i<ctsz; i++) {
+ matchCostTable[i] = 0.5F;
+ mismatchCostTable[i] = 0.5F;
+ }
+ }
+
+ {
+ decoder.initializeStates();
+ // Each sample of history[] carries its history.
+ // So we only have to process every iRate-th sample.
+ const unsigned step = decoder.iRate();
+ // input pointer
+ const uint32_t *ip = history + step - 1;
+ // output pointers
+ char *op = target.begin();
+ const char *const opt = target.end();
+ // table pointers
+ const float* match = matchCostTable;
+ const float* mismatch = mismatchCostTable;
+ size_t oCount = 0;
+ while (op<opt) {
+ // Viterbi algorithm
+ assert(match-matchCostTable<(int)(sizeof(matchCostTable)/sizeof(matchCostTable[0])-1));
+ assert(mismatch-mismatchCostTable<(int)(sizeof(mismatchCostTable)/sizeof(mismatchCostTable[0])-1));
+ const ViterbiTCH_AFS12_2::vCand &minCost = decoder.step(*ip, match, mismatch);
+ ip += step;
+ match += step;
+ mismatch += step;
+ // output
+ if (oCount>=deferral) *op++ = (minCost.iState >> deferral)&0x01;
+ oCount++;
+ }
+ }
+}
+
+
+
+ViterbiTCH_AFS10_2::ViterbiTCH_AFS10_2()
+{
+ assert(mDeferral < 32);
+ mCoeffs[0] = 0x01b;
+ mCoeffsFB[0] = 0x01f;
+ mCoeffs[1] = 0x015;
+ mCoeffsFB[1] = 0x01f;
+ mCoeffs[2] = 0x01f;
+ mCoeffsFB[2] = 0x01f;
+ for (unsigned i = 0; i < mIRate; i++) {
+ computeStateTables(i);
+ }
+ computeGeneratorTable();
+}
+
+
+
+
+void ViterbiTCH_AFS10_2::initializeStates()
+{
+ for (unsigned i=0; i<mIStates; i++) vitClear(mSurvivors[i]);
+ for (unsigned i=0; i<mNumCands; i++) vitClear(mCandidates[i]);
+}
+
+
+
+void ViterbiTCH_AFS10_2::computeStateTables(unsigned g)
+{
+ assert(g<mIRate);
+ for (unsigned state=0; state<mIStates; state++) {
+ for (unsigned in = 0; in <= 1; in++) {
+ uint32_t inputVal = (state<<1) | in;
+ mStateTable[g][inputVal] = applyPoly(inputVal, mCoeffs[g] ^ mCoeffsFB[g], mOrder+1) ^ in;
+ }
+ }
+}
+
+void ViterbiTCH_AFS10_2::computeGeneratorTable()
+{
+ for (unsigned index=0; index<mIStates*2; index++) {
+ uint32_t t = 0;
+ for (unsigned i = 0; i < mIRate; i++) {
+ t = (t << 1) | mStateTable[i][index];
+ }
+ mGeneratorTable[index] = t;
+ }
+}
+
+
+
+
+
+
+void ViterbiTCH_AFS10_2::branchCandidates()
+{
+ // Branch to generate new input states.
+ const vCand *sp = mSurvivors;
+ for (unsigned cand=0; cand<mNumCands; cand+=2) {
+ uint32_t oStateShifted = (sp->oState) << mIRate;
+ for (unsigned in = 0; in <= 1; in++) {
+ mCandidates[cand+in].iState = ((sp->iState) << 1) | in;
+ mCandidates[cand+in].cost = sp->cost;
+ uint32_t outputs = oStateShifted;
+ for (unsigned out = 0; out < mIRate; out++) {
+ char feedback = applyPoly(sp->rState[out], mCoeffsFB[out] ^ 1, mOrder+1);
+ char rState = (((sp->rState[out]) ^ feedback) << 1) | in;
+ mCandidates[cand+in].rState[out] = rState;
+ outputs |= (mGeneratorTable[rState & mCMask] & (1 << (mIRate - out - 1)));
+ }
+ mCandidates[cand+in].oState = outputs;
+ }
+ sp++;
+ }
+}
+
+
+void ViterbiTCH_AFS10_2::getSoftCostMetrics(const uint32_t inSample, const float *matchCost, const float *mismatchCost)
+{
+ const float *cTab[2] = {matchCost,mismatchCost};
+ for (unsigned i=0; i<mNumCands; i++) {
+ vCand& thisCand = mCandidates[i];
+ const unsigned mismatched = inSample ^ (thisCand.oState);
+ for (unsigned i = 0; i < mIRate; i++) {
+ thisCand.cost += cTab[(mismatched>>i)&0x01][mIRate-i-1];
+ }
+ }
+}
+
+
+void ViterbiTCH_AFS10_2::pruneCandidates()
+{
+ const vCand* c1 = mCandidates; // 0-prefix
+ const vCand* c2 = mCandidates + mIStates; // 1-prefix
+ for (unsigned i=0; i<mIStates; i++) {
+ if (c1[i].cost < c2[i].cost) mSurvivors[i] = c1[i];
+ else mSurvivors[i] = c2[i];
+ }
+}
+
+
+const ViterbiTCH_AFS10_2::vCand& ViterbiTCH_AFS10_2::minCost() const
+{
+ int minIndex = 0;
+ float minCost = mSurvivors[0].cost;
+ for (unsigned i=1; i<mIStates; i++) {
+ const float thisCost = mSurvivors[i].cost;
+ if (thisCost>=minCost) continue;
+ minCost = thisCost;
+ minIndex=i;
+ }
+ return mSurvivors[minIndex];
+}
+
+
+const ViterbiTCH_AFS10_2::vCand& ViterbiTCH_AFS10_2::step(uint32_t inSample, const float *probs, const float *iprobs)
+{
+ branchCandidates();
+ getSoftCostMetrics(inSample,probs,iprobs);
+ pruneCandidates();
+ return minCost();
+}
+
+
+
+void ViterbiTCH_AFS10_2::decode(const SoftVector &in, BitVector& target)
+{
+ ViterbiTCH_AFS10_2 &decoder = *this;
+ const size_t sz = in.size() - 12;
+ const unsigned deferral = decoder.deferral();
+ const size_t ctsz = sz + deferral*decoder.iRate();
+ assert(sz == decoder.iRate()*target.size());
+
+ // Build a "history" array where each element contains the full history.
+ uint32_t history[ctsz];
+ {
+ BitVector bits = in.sliced();
+ uint32_t accum = 0;
+ for (size_t i=0; i<sz; i++) {
+ accum = (accum<<1) | bits.bit(i);
+ history[i] = accum;
+ }
+ // Repeat last bit at the end.
+ for (size_t i=sz; i<ctsz; i++) {
+ accum = (accum<<1) | (accum & 0x01);
+ history[i] = accum;
+ }
+ }
+
+ // Precompute metric tables.
+ float matchCostTable[ctsz];
+ float mismatchCostTable[ctsz];
+ {
+ const float *dp = in.begin();
+ for (size_t i=0; i<sz; i++) {
+ // pVal is the probability that a bit is correct.
+ // ipVal is the probability that a bit is incorrect.
+ float pVal = dp[i];
+ if (pVal>0.5F) pVal = 1.0F-pVal;
+ float ipVal = 1.0F-pVal;
+ // This is a cheap approximation to an ideal cost function.
+ if (pVal<0.01F) pVal = 0.01;
+ if (ipVal<0.01F) ipVal = 0.01;
+ matchCostTable[i] = 0.25F/ipVal;
+ mismatchCostTable[i] = 0.25F/pVal;
+ }
+
+ // pad end of table with unknowns
+ for (size_t i=sz; i<ctsz; i++) {
+ matchCostTable[i] = 0.5F;
+ mismatchCostTable[i] = 0.5F;
+ }
+ }
+
+ {
+ decoder.initializeStates();
+ // Each sample of history[] carries its history.
+ // So we only have to process every iRate-th sample.
+ const unsigned step = decoder.iRate();
+ // input pointer
+ const uint32_t *ip = history + step - 1;
+ // output pointers
+ char *op = target.begin();
+ const char *const opt = target.end();
+ // table pointers
+ const float* match = matchCostTable;
+ const float* mismatch = mismatchCostTable;
+ size_t oCount = 0;
+ while (op<opt) {
+ // Viterbi algorithm
+ assert(match-matchCostTable<(int)(sizeof(matchCostTable)/sizeof(matchCostTable[0])-1));
+ assert(mismatch-mismatchCostTable<(int)(sizeof(mismatchCostTable)/sizeof(mismatchCostTable[0])-1));
+ const ViterbiTCH_AFS10_2::vCand &minCost = decoder.step(*ip, match, mismatch);
+ ip += step;
+ match += step;
+ mismatch += step;
+ // output
+ if (oCount>=deferral) *op++ = (minCost.iState >> deferral)&0x01;
+ oCount++;
+ }
+ }
+}
+
+
+
+ViterbiTCH_AFS7_95::ViterbiTCH_AFS7_95()
+{
+ assert(mDeferral < 32);
+ mCoeffs[0] = 0x06d;
+ mCoeffsFB[0] = 0x06d;
+ mCoeffs[1] = 0x053;
+ mCoeffsFB[1] = 0x06d;
+ mCoeffs[2] = 0x05f;
+ mCoeffsFB[2] = 0x06d;
+ for (unsigned i = 0; i < mIRate; i++) {
+ computeStateTables(i);
+ }
+ computeGeneratorTable();
+}
+
+
+
+
+void ViterbiTCH_AFS7_95::initializeStates()
+{
+ for (unsigned i=0; i<mIStates; i++) vitClear(mSurvivors[i]);
+ for (unsigned i=0; i<mNumCands; i++) vitClear(mCandidates[i]);
+}
+
+
+
+void ViterbiTCH_AFS7_95::computeStateTables(unsigned g)
+{
+ assert(g<mIRate);
+ for (unsigned state=0; state<mIStates; state++) {
+ for (unsigned in = 0; in <= 1; in++) {
+ uint32_t inputVal = (state<<1) | in;
+ mStateTable[g][inputVal] = applyPoly(inputVal, mCoeffs[g] ^ mCoeffsFB[g], mOrder+1) ^ in;
+ }
+ }
+}
+
+void ViterbiTCH_AFS7_95::computeGeneratorTable()
+{
+ for (unsigned index=0; index<mIStates*2; index++) {
+ uint32_t t = 0;
+ for (unsigned i = 0; i < mIRate; i++) {
+ t = (t << 1) | mStateTable[i][index];
+ }
+ mGeneratorTable[index] = t;
+ }
+}
+
+
+
+
+
+
+void ViterbiTCH_AFS7_95::branchCandidates()
+{
+ // Branch to generate new input states.
+ const vCand *sp = mSurvivors;
+ for (unsigned cand=0; cand<mNumCands; cand+=2) {
+ uint32_t oStateShifted = (sp->oState) << mIRate;
+ for (unsigned in = 0; in <= 1; in++) {
+ mCandidates[cand+in].iState = ((sp->iState) << 1) | in;
+ mCandidates[cand+in].cost = sp->cost;
+ uint32_t outputs = oStateShifted;
+ for (unsigned out = 0; out < mIRate; out++) {
+ char feedback = applyPoly(sp->rState[out], mCoeffsFB[out] ^ 1, mOrder+1);
+ char rState = (((sp->rState[out]) ^ feedback) << 1) | in;
+ mCandidates[cand+in].rState[out] = rState;
+ outputs |= (mGeneratorTable[rState & mCMask] & (1 << (mIRate - out - 1)));
+ }
+ mCandidates[cand+in].oState = outputs;
+ }
+ sp++;
+ }
+}
+
+
+void ViterbiTCH_AFS7_95::getSoftCostMetrics(const uint32_t inSample, const float *matchCost, const float *mismatchCost)
+{
+ const float *cTab[2] = {matchCost,mismatchCost};
+ for (unsigned i=0; i<mNumCands; i++) {
+ vCand& thisCand = mCandidates[i];
+ const unsigned mismatched = inSample ^ (thisCand.oState);
+ for (unsigned i = 0; i < mIRate; i++) {
+ thisCand.cost += cTab[(mismatched>>i)&0x01][mIRate-i-1];
+ }
+ }
+}
+
+
+void ViterbiTCH_AFS7_95::pruneCandidates()
+{
+ const vCand* c1 = mCandidates; // 0-prefix
+ const vCand* c2 = mCandidates + mIStates; // 1-prefix
+ for (unsigned i=0; i<mIStates; i++) {
+ if (c1[i].cost < c2[i].cost) mSurvivors[i] = c1[i];
+ else mSurvivors[i] = c2[i];
+ }
+}
+
+
+const ViterbiTCH_AFS7_95::vCand& ViterbiTCH_AFS7_95::minCost() const
+{
+ int minIndex = 0;
+ float minCost = mSurvivors[0].cost;
+ for (unsigned i=1; i<mIStates; i++) {
+ const float thisCost = mSurvivors[i].cost;
+ if (thisCost>=minCost) continue;
+ minCost = thisCost;
+ minIndex=i;
+ }
+ return mSurvivors[minIndex];
+}
+
+
+const ViterbiTCH_AFS7_95::vCand& ViterbiTCH_AFS7_95::step(uint32_t inSample, const float *probs, const float *iprobs)
+{
+ branchCandidates();
+ getSoftCostMetrics(inSample,probs,iprobs);
+ pruneCandidates();
+ return minCost();
+}
+
+
+
+void ViterbiTCH_AFS7_95::decode(const SoftVector &in, BitVector& target)
+{
+ ViterbiTCH_AFS7_95 &decoder = *this;
+ const size_t sz = in.size() - 18;
+ const unsigned deferral = decoder.deferral();
+ const size_t ctsz = sz + deferral*decoder.iRate();
+ assert(sz == decoder.iRate()*target.size());
+
+ // Build a "history" array where each element contains the full history.
+ uint32_t history[ctsz];
+ {
+ BitVector bits = in.sliced();
+ uint32_t accum = 0;
+ for (size_t i=0; i<sz; i++) {
+ accum = (accum<<1) | bits.bit(i);
+ history[i] = accum;
+ }
+ // Repeat last bit at the end.
+ for (size_t i=sz; i<ctsz; i++) {
+ accum = (accum<<1) | (accum & 0x01);
+ history[i] = accum;
+ }
+ }
+
+ // Precompute metric tables.
+ float matchCostTable[ctsz];
+ float mismatchCostTable[ctsz];
+ {
+ const float *dp = in.begin();
+ for (size_t i=0; i<sz; i++) {
+ // pVal is the probability that a bit is correct.
+ // ipVal is the probability that a bit is incorrect.
+ float pVal = dp[i];
+ if (pVal>0.5F) pVal = 1.0F-pVal;
+ float ipVal = 1.0F-pVal;
+ // This is a cheap approximation to an ideal cost function.
+ if (pVal<0.01F) pVal = 0.01;
+ if (ipVal<0.01F) ipVal = 0.01;
+ matchCostTable[i] = 0.25F/ipVal;
+ mismatchCostTable[i] = 0.25F/pVal;
+ }
+
+ // pad end of table with unknowns
+ for (size_t i=sz; i<ctsz; i++) {
+ matchCostTable[i] = 0.5F;
+ mismatchCostTable[i] = 0.5F;
+ }
+ }
+
+ {
+ decoder.initializeStates();
+ // Each sample of history[] carries its history.
+ // So we only have to process every iRate-th sample.
+ const unsigned step = decoder.iRate();
+ // input pointer
+ const uint32_t *ip = history + step - 1;
+ // output pointers
+ char *op = target.begin();
+ const char *const opt = target.end();
+ // table pointers
+ const float* match = matchCostTable;
+ const float* mismatch = mismatchCostTable;
+ size_t oCount = 0;
+ while (op<opt) {
+ // Viterbi algorithm
+ assert(match-matchCostTable<(int)(sizeof(matchCostTable)/sizeof(matchCostTable[0])-1));
+ assert(mismatch-mismatchCostTable<(int)(sizeof(mismatchCostTable)/sizeof(mismatchCostTable[0])-1));
+ const ViterbiTCH_AFS7_95::vCand &minCost = decoder.step(*ip, match, mismatch);
+ ip += step;
+ match += step;
+ mismatch += step;
+ // output
+ if (oCount>=deferral) *op++ = (minCost.iState >> deferral)&0x01;
+ oCount++;
+ }
+ }
+}
+
+
+
+ViterbiTCH_AFS7_4::ViterbiTCH_AFS7_4()
+{
+ assert(mDeferral < 32);
+ mCoeffs[0] = 0x01b;
+ mCoeffsFB[0] = 0x01f;
+ mCoeffs[1] = 0x015;
+ mCoeffsFB[1] = 0x01f;
+ mCoeffs[2] = 0x01f;
+ mCoeffsFB[2] = 0x01f;
+ for (unsigned i = 0; i < mIRate; i++) {
+ computeStateTables(i);
+ }
+ computeGeneratorTable();
+}
+
+
+
+
+void ViterbiTCH_AFS7_4::initializeStates()
+{
+ for (unsigned i=0; i<mIStates; i++) vitClear(mSurvivors[i]);
+ for (unsigned i=0; i<mNumCands; i++) vitClear(mCandidates[i]);
+}
+
+
+
+void ViterbiTCH_AFS7_4::computeStateTables(unsigned g)
+{
+ assert(g<mIRate);
+ for (unsigned state=0; state<mIStates; state++) {
+ for (unsigned in = 0; in <= 1; in++) {
+ uint32_t inputVal = (state<<1) | in;
+ mStateTable[g][inputVal] = applyPoly(inputVal, mCoeffs[g] ^ mCoeffsFB[g], mOrder+1) ^ in;
+ }
+ }
+}
+
+void ViterbiTCH_AFS7_4::computeGeneratorTable()
+{
+ for (unsigned index=0; index<mIStates*2; index++) {
+ uint32_t t = 0;
+ for (unsigned i = 0; i < mIRate; i++) {
+ t = (t << 1) | mStateTable[i][index];
+ }
+ mGeneratorTable[index] = t;
+ }
+}
+
+
+
+
+
+
+void ViterbiTCH_AFS7_4::branchCandidates()
+{
+ // Branch to generate new input states.
+ const vCand *sp = mSurvivors;
+ for (unsigned cand=0; cand<mNumCands; cand+=2) {
+ uint32_t oStateShifted = (sp->oState) << mIRate;
+ for (unsigned in = 0; in <= 1; in++) {
+ mCandidates[cand+in].iState = ((sp->iState) << 1) | in;
+ mCandidates[cand+in].cost = sp->cost;
+ uint32_t outputs = oStateShifted;
+ for (unsigned out = 0; out < mIRate; out++) {
+ char feedback = applyPoly(sp->rState[out], mCoeffsFB[out] ^ 1, mOrder+1);
+ char rState = (((sp->rState[out]) ^ feedback) << 1) | in;
+ mCandidates[cand+in].rState[out] = rState;
+ outputs |= (mGeneratorTable[rState & mCMask] & (1 << (mIRate - out - 1)));
+ }
+ mCandidates[cand+in].oState = outputs;
+ }
+ sp++;
+ }
+}
+
+
+void ViterbiTCH_AFS7_4::getSoftCostMetrics(const uint32_t inSample, const float *matchCost, const float *mismatchCost)
+{
+ const float *cTab[2] = {matchCost,mismatchCost};
+ for (unsigned i=0; i<mNumCands; i++) {
+ vCand& thisCand = mCandidates[i];
+ const unsigned mismatched = inSample ^ (thisCand.oState);
+ for (unsigned i = 0; i < mIRate; i++) {
+ thisCand.cost += cTab[(mismatched>>i)&0x01][mIRate-i-1];
+ }
+ }
+}
+
+
+void ViterbiTCH_AFS7_4::pruneCandidates()
+{
+ const vCand* c1 = mCandidates; // 0-prefix
+ const vCand* c2 = mCandidates + mIStates; // 1-prefix
+ for (unsigned i=0; i<mIStates; i++) {
+ if (c1[i].cost < c2[i].cost) mSurvivors[i] = c1[i];
+ else mSurvivors[i] = c2[i];
+ }
+}
+
+
+const ViterbiTCH_AFS7_4::vCand& ViterbiTCH_AFS7_4::minCost() const
+{
+ int minIndex = 0;
+ float minCost = mSurvivors[0].cost;
+ for (unsigned i=1; i<mIStates; i++) {
+ const float thisCost = mSurvivors[i].cost;
+ if (thisCost>=minCost) continue;
+ minCost = thisCost;
+ minIndex=i;
+ }
+ return mSurvivors[minIndex];
+}
+
+
+const ViterbiTCH_AFS7_4::vCand& ViterbiTCH_AFS7_4::step(uint32_t inSample, const float *probs, const float *iprobs)
+{
+ branchCandidates();
+ getSoftCostMetrics(inSample,probs,iprobs);
+ pruneCandidates();
+ return minCost();
+}
+
+
+
+void ViterbiTCH_AFS7_4::decode(const SoftVector &in, BitVector& target)
+{
+ ViterbiTCH_AFS7_4 &decoder = *this;
+ const size_t sz = in.size() - 12;
+ const unsigned deferral = decoder.deferral();
+ const size_t ctsz = sz + deferral*decoder.iRate();
+ assert(sz == decoder.iRate()*target.size());
+
+ // Build a "history" array where each element contains the full history.
+ uint32_t history[ctsz];
+ {
+ BitVector bits = in.sliced();
+ uint32_t accum = 0;
+ for (size_t i=0; i<sz; i++) {
+ accum = (accum<<1) | bits.bit(i);
+ history[i] = accum;
+ }
+ // Repeat last bit at the end.
+ for (size_t i=sz; i<ctsz; i++) {
+ accum = (accum<<1) | (accum & 0x01);
+ history[i] = accum;
+ }
+ }
+
+ // Precompute metric tables.
+ float matchCostTable[ctsz];
+ float mismatchCostTable[ctsz];
+ {
+ const float *dp = in.begin();
+ for (size_t i=0; i<sz; i++) {
+ // pVal is the probability that a bit is correct.
+ // ipVal is the probability that a bit is incorrect.
+ float pVal = dp[i];
+ if (pVal>0.5F) pVal = 1.0F-pVal;
+ float ipVal = 1.0F-pVal;
+ // This is a cheap approximation to an ideal cost function.
+ if (pVal<0.01F) pVal = 0.01;
+ if (ipVal<0.01F) ipVal = 0.01;
+ matchCostTable[i] = 0.25F/ipVal;
+ mismatchCostTable[i] = 0.25F/pVal;
+ }
+
+ // pad end of table with unknowns
+ for (size_t i=sz; i<ctsz; i++) {
+ matchCostTable[i] = 0.5F;
+ mismatchCostTable[i] = 0.5F;
+ }
+ }
+
+ {
+ decoder.initializeStates();
+ // Each sample of history[] carries its history.
+ // So we only have to process every iRate-th sample.
+ const unsigned step = decoder.iRate();
+ // input pointer
+ const uint32_t *ip = history + step - 1;
+ // output pointers
+ char *op = target.begin();
+ const char *const opt = target.end();
+ // table pointers
+ const float* match = matchCostTable;
+ const float* mismatch = mismatchCostTable;
+ size_t oCount = 0;
+ while (op<opt) {
+ // Viterbi algorithm
+ assert(match-matchCostTable<(int)(sizeof(matchCostTable)/sizeof(matchCostTable[0])-1));
+ assert(mismatch-mismatchCostTable<(int)(sizeof(mismatchCostTable)/sizeof(mismatchCostTable[0])-1));
+ const ViterbiTCH_AFS7_4::vCand &minCost = decoder.step(*ip, match, mismatch);
+ ip += step;
+ match += step;
+ mismatch += step;
+ // output
+ if (oCount>=deferral) *op++ = (minCost.iState >> deferral)&0x01;
+ oCount++;
+ }
+ }
+}
+
+
+
+ViterbiTCH_AFS6_7::ViterbiTCH_AFS6_7()
+{
+ assert(mDeferral < 32);
+ mCoeffs[0] = 0x01b;
+ mCoeffsFB[0] = 0x01f;
+ mCoeffs[1] = 0x015;
+ mCoeffsFB[1] = 0x01f;
+ mCoeffs[2] = 0x01f;
+ mCoeffsFB[2] = 0x01f;
+ mCoeffs[3] = 0x01f;
+ mCoeffsFB[3] = 0x01f;
+ for (unsigned i = 0; i < mIRate; i++) {
+ computeStateTables(i);
+ }
+ computeGeneratorTable();
+}
+
+
+
+
+void ViterbiTCH_AFS6_7::initializeStates()
+{
+ for (unsigned i=0; i<mIStates; i++) vitClear(mSurvivors[i]);
+ for (unsigned i=0; i<mNumCands; i++) vitClear(mCandidates[i]);
+}
+
+
+
+void ViterbiTCH_AFS6_7::computeStateTables(unsigned g)
+{
+ assert(g<mIRate);
+ for (unsigned state=0; state<mIStates; state++) {
+ for (unsigned in = 0; in <= 1; in++) {
+ uint32_t inputVal = (state<<1) | in;
+ mStateTable[g][inputVal] = applyPoly(inputVal, mCoeffs[g] ^ mCoeffsFB[g], mOrder+1) ^ in;
+ }
+ }
+}
+
+void ViterbiTCH_AFS6_7::computeGeneratorTable()
+{
+ for (unsigned index=0; index<mIStates*2; index++) {
+ uint32_t t = 0;
+ for (unsigned i = 0; i < mIRate; i++) {
+ t = (t << 1) | mStateTable[i][index];
+ }
+ mGeneratorTable[index] = t;
+ }
+}
+
+
+
+
+
+
+void ViterbiTCH_AFS6_7::branchCandidates()
+{
+ // Branch to generate new input states.
+ const vCand *sp = mSurvivors;
+ for (unsigned cand=0; cand<mNumCands; cand+=2) {
+ uint32_t oStateShifted = (sp->oState) << mIRate;
+ for (unsigned in = 0; in <= 1; in++) {
+ mCandidates[cand+in].iState = ((sp->iState) << 1) | in;
+ mCandidates[cand+in].cost = sp->cost;
+ uint32_t outputs = oStateShifted;
+ for (unsigned out = 0; out < mIRate; out++) {
+ char feedback = applyPoly(sp->rState[out], mCoeffsFB[out] ^ 1, mOrder+1);
+ char rState = (((sp->rState[out]) ^ feedback) << 1) | in;
+ mCandidates[cand+in].rState[out] = rState;
+ outputs |= (mGeneratorTable[rState & mCMask] & (1 << (mIRate - out - 1)));
+ }
+ mCandidates[cand+in].oState = outputs;
+ }
+ sp++;
+ }
+}
+
+
+void ViterbiTCH_AFS6_7::getSoftCostMetrics(const uint32_t inSample, const float *matchCost, const float *mismatchCost)
+{
+ const float *cTab[2] = {matchCost,mismatchCost};
+ for (unsigned i=0; i<mNumCands; i++) {
+ vCand& thisCand = mCandidates[i];
+ const unsigned mismatched = inSample ^ (thisCand.oState);
+ for (unsigned i = 0; i < mIRate; i++) {
+ thisCand.cost += cTab[(mismatched>>i)&0x01][mIRate-i-1];
+ }
+ }
+}
+
+
+void ViterbiTCH_AFS6_7::pruneCandidates()
+{
+ const vCand* c1 = mCandidates; // 0-prefix
+ const vCand* c2 = mCandidates + mIStates; // 1-prefix
+ for (unsigned i=0; i<mIStates; i++) {
+ if (c1[i].cost < c2[i].cost) mSurvivors[i] = c1[i];
+ else mSurvivors[i] = c2[i];
+ }
+}
+
+
+const ViterbiTCH_AFS6_7::vCand& ViterbiTCH_AFS6_7::minCost() const
+{
+ int minIndex = 0;
+ float minCost = mSurvivors[0].cost;
+ for (unsigned i=1; i<mIStates; i++) {
+ const float thisCost = mSurvivors[i].cost;
+ if (thisCost>=minCost) continue;
+ minCost = thisCost;
+ minIndex=i;
+ }
+ return mSurvivors[minIndex];
+}
+
+
+const ViterbiTCH_AFS6_7::vCand& ViterbiTCH_AFS6_7::step(uint32_t inSample, const float *probs, const float *iprobs)
+{
+ branchCandidates();
+ getSoftCostMetrics(inSample,probs,iprobs);
+ pruneCandidates();
+ return minCost();
+}
+
+
+
+void ViterbiTCH_AFS6_7::decode(const SoftVector &in, BitVector& target)
+{
+ ViterbiTCH_AFS6_7 &decoder = *this;
+ const size_t sz = in.size() - 16;
+ const unsigned deferral = decoder.deferral();
+ const size_t ctsz = sz + deferral*decoder.iRate();
+ assert(sz == decoder.iRate()*target.size());
+
+ // Build a "history" array where each element contains the full history.
+ uint32_t history[ctsz];
+ {
+ BitVector bits = in.sliced();
+ uint32_t accum = 0;
+ for (size_t i=0; i<sz; i++) {
+ accum = (accum<<1) | bits.bit(i);
+ history[i] = accum;
+ }
+ // Repeat last bit at the end.
+ for (size_t i=sz; i<ctsz; i++) {
+ accum = (accum<<1) | (accum & 0x01);
+ history[i] = accum;
+ }
+ }
+
+ // Precompute metric tables.
+ float matchCostTable[ctsz];
+ float mismatchCostTable[ctsz];
+ {
+ const float *dp = in.begin();
+ for (size_t i=0; i<sz; i++) {
+ // pVal is the probability that a bit is correct.
+ // ipVal is the probability that a bit is incorrect.
+ float pVal = dp[i];
+ if (pVal>0.5F) pVal = 1.0F-pVal;
+ float ipVal = 1.0F-pVal;
+ // This is a cheap approximation to an ideal cost function.
+ if (pVal<0.01F) pVal = 0.01;
+ if (ipVal<0.01F) ipVal = 0.01;
+ matchCostTable[i] = 0.25F/ipVal;
+ mismatchCostTable[i] = 0.25F/pVal;
+ }
+
+ // pad end of table with unknowns
+ for (size_t i=sz; i<ctsz; i++) {
+ matchCostTable[i] = 0.5F;
+ mismatchCostTable[i] = 0.5F;
+ }
+ }
+
+ {
+ decoder.initializeStates();
+ // Each sample of history[] carries its history.
+ // So we only have to process every iRate-th sample.
+ const unsigned step = decoder.iRate();
+ // input pointer
+ const uint32_t *ip = history + step - 1;
+ // output pointers
+ char *op = target.begin();
+ const char *const opt = target.end();
+ // table pointers
+ const float* match = matchCostTable;
+ const float* mismatch = mismatchCostTable;
+ size_t oCount = 0;
+ while (op<opt) {
+ // Viterbi algorithm
+ assert(match-matchCostTable<(int)(sizeof(matchCostTable)/sizeof(matchCostTable[0])-1));
+ assert(mismatch-mismatchCostTable<(int)(sizeof(mismatchCostTable)/sizeof(mismatchCostTable[0])-1));
+ const ViterbiTCH_AFS6_7::vCand &minCost = decoder.step(*ip, match, mismatch);
+ ip += step;
+ match += step;
+ mismatch += step;
+ // output
+ if (oCount>=deferral) *op++ = (minCost.iState >> deferral)&0x01;
+ oCount++;
+ }
+ }
+}
+
+
+
+ViterbiTCH_AFS5_9::ViterbiTCH_AFS5_9()
+{
+ assert(mDeferral < 32);
+ mCoeffs[0] = 0x06d;
+ mCoeffsFB[0] = 0x05f;
+ mCoeffs[1] = 0x053;
+ mCoeffsFB[1] = 0x05f;
+ mCoeffs[2] = 0x05f;
+ mCoeffsFB[2] = 0x05f;
+ mCoeffs[3] = 0x05f;
+ mCoeffsFB[3] = 0x05f;
+ for (unsigned i = 0; i < mIRate; i++) {
+ computeStateTables(i);
+ }
+ computeGeneratorTable();
+}
+
+
+
+
+void ViterbiTCH_AFS5_9::initializeStates()
+{
+ for (unsigned i=0; i<mIStates; i++) vitClear(mSurvivors[i]);
+ for (unsigned i=0; i<mNumCands; i++) vitClear(mCandidates[i]);
+}
+
+
+
+void ViterbiTCH_AFS5_9::computeStateTables(unsigned g)
+{
+ assert(g<mIRate);
+ for (unsigned state=0; state<mIStates; state++) {
+ for (unsigned in = 0; in <= 1; in++) {
+ uint32_t inputVal = (state<<1) | in;
+ mStateTable[g][inputVal] = applyPoly(inputVal, mCoeffs[g] ^ mCoeffsFB[g], mOrder+1) ^ in;
+ }
+ }
+}
+
+void ViterbiTCH_AFS5_9::computeGeneratorTable()
+{
+ for (unsigned index=0; index<mIStates*2; index++) {
+ uint32_t t = 0;
+ for (unsigned i = 0; i < mIRate; i++) {
+ t = (t << 1) | mStateTable[i][index];
+ }
+ mGeneratorTable[index] = t;
+ }
+}
+
+
+
+
+
+
+void ViterbiTCH_AFS5_9::branchCandidates()
+{
+ // Branch to generate new input states.
+ const vCand *sp = mSurvivors;
+ for (unsigned cand=0; cand<mNumCands; cand+=2) {
+ uint32_t oStateShifted = (sp->oState) << mIRate;
+ for (unsigned in = 0; in <= 1; in++) {
+ mCandidates[cand+in].iState = ((sp->iState) << 1) | in;
+ mCandidates[cand+in].cost = sp->cost;
+ uint32_t outputs = oStateShifted;
+ for (unsigned out = 0; out < mIRate; out++) {
+ char feedback = applyPoly(sp->rState[out], mCoeffsFB[out] ^ 1, mOrder+1);
+ char rState = (((sp->rState[out]) ^ feedback) << 1) | in;
+ mCandidates[cand+in].rState[out] = rState;
+ outputs |= (mGeneratorTable[rState & mCMask] & (1 << (mIRate - out - 1)));
+ }
+ mCandidates[cand+in].oState = outputs;
+ }
+ sp++;
+ }
+}
+
+
+void ViterbiTCH_AFS5_9::getSoftCostMetrics(const uint32_t inSample, const float *matchCost, const float *mismatchCost)
+{
+ const float *cTab[2] = {matchCost,mismatchCost};
+ for (unsigned i=0; i<mNumCands; i++) {
+ vCand& thisCand = mCandidates[i];
+ const unsigned mismatched = inSample ^ (thisCand.oState);
+ for (unsigned i = 0; i < mIRate; i++) {
+ thisCand.cost += cTab[(mismatched>>i)&0x01][mIRate-i-1];
+ }
+ }
+}
+
+
+void ViterbiTCH_AFS5_9::pruneCandidates()
+{
+ const vCand* c1 = mCandidates; // 0-prefix
+ const vCand* c2 = mCandidates + mIStates; // 1-prefix
+ for (unsigned i=0; i<mIStates; i++) {
+ if (c1[i].cost < c2[i].cost) mSurvivors[i] = c1[i];
+ else mSurvivors[i] = c2[i];
+ }
+}
+
+
+const ViterbiTCH_AFS5_9::vCand& ViterbiTCH_AFS5_9::minCost() const
+{
+ int minIndex = 0;
+ float minCost = mSurvivors[0].cost;
+ for (unsigned i=1; i<mIStates; i++) {
+ const float thisCost = mSurvivors[i].cost;
+ if (thisCost>=minCost) continue;
+ minCost = thisCost;
+ minIndex=i;
+ }
+ return mSurvivors[minIndex];
+}
+
+
+const ViterbiTCH_AFS5_9::vCand& ViterbiTCH_AFS5_9::step(uint32_t inSample, const float *probs, const float *iprobs)
+{
+ branchCandidates();
+ getSoftCostMetrics(inSample,probs,iprobs);
+ pruneCandidates();
+ return minCost();
+}
+
+
+
+void ViterbiTCH_AFS5_9::decode(const SoftVector &in, BitVector& target)
+{
+ ViterbiTCH_AFS5_9 &decoder = *this;
+ const size_t sz = in.size() - 24;
+ const unsigned deferral = decoder.deferral();
+ const size_t ctsz = sz + deferral*decoder.iRate();
+ assert(sz == decoder.iRate()*target.size());
+
+ // Build a "history" array where each element contains the full history.
+ uint32_t history[ctsz];
+ {
+ BitVector bits = in.sliced();
+ uint32_t accum = 0;
+ for (size_t i=0; i<sz; i++) {
+ accum = (accum<<1) | bits.bit(i);
+ history[i] = accum;
+ }
+ // Repeat last bit at the end.
+ for (size_t i=sz; i<ctsz; i++) {
+ accum = (accum<<1) | (accum & 0x01);
+ history[i] = accum;
+ }
+ }
+
+ // Precompute metric tables.
+ float matchCostTable[ctsz];
+ float mismatchCostTable[ctsz];
+ {
+ const float *dp = in.begin();
+ for (size_t i=0; i<sz; i++) {
+ // pVal is the probability that a bit is correct.
+ // ipVal is the probability that a bit is incorrect.
+ float pVal = dp[i];
+ if (pVal>0.5F) pVal = 1.0F-pVal;
+ float ipVal = 1.0F-pVal;
+ // This is a cheap approximation to an ideal cost function.
+ if (pVal<0.01F) pVal = 0.01;
+ if (ipVal<0.01F) ipVal = 0.01;
+ matchCostTable[i] = 0.25F/ipVal;
+ mismatchCostTable[i] = 0.25F/pVal;
+ }
+
+ // pad end of table with unknowns
+ for (size_t i=sz; i<ctsz; i++) {
+ matchCostTable[i] = 0.5F;
+ mismatchCostTable[i] = 0.5F;
+ }
+ }
+
+ {
+ decoder.initializeStates();
+ // Each sample of history[] carries its history.
+ // So we only have to process every iRate-th sample.
+ const unsigned step = decoder.iRate();
+ // input pointer
+ const uint32_t *ip = history + step - 1;
+ // output pointers
+ char *op = target.begin();
+ const char *const opt = target.end();
+ // table pointers
+ const float* match = matchCostTable;
+ const float* mismatch = mismatchCostTable;
+ size_t oCount = 0;
+ while (op<opt) {
+ // Viterbi algorithm
+ assert(match-matchCostTable<(int)(sizeof(matchCostTable)/sizeof(matchCostTable[0])-1));
+ assert(mismatch-mismatchCostTable<(int)(sizeof(mismatchCostTable)/sizeof(mismatchCostTable[0])-1));
+ const ViterbiTCH_AFS5_9::vCand &minCost = decoder.step(*ip, match, mismatch);
+ ip += step;
+ match += step;
+ mismatch += step;
+ // output
+ if (oCount>=deferral) *op++ = (minCost.iState >> deferral)&0x01;
+ oCount++;
+ }
+ }
+}
+
+
+
+ViterbiTCH_AFS5_15::ViterbiTCH_AFS5_15()
+{
+ assert(mDeferral < 32);
+ mCoeffs[0] = 0x01b;
+ mCoeffsFB[0] = 0x01f;
+ mCoeffs[1] = 0x01b;
+ mCoeffsFB[1] = 0x01f;
+ mCoeffs[2] = 0x015;
+ mCoeffsFB[2] = 0x01f;
+ mCoeffs[3] = 0x01f;
+ mCoeffsFB[3] = 0x01f;
+ mCoeffs[4] = 0x01f;
+ mCoeffsFB[4] = 0x01f;
+ for (unsigned i = 0; i < mIRate; i++) {
+ computeStateTables(i);
+ }
+ computeGeneratorTable();
+}
+
+
+
+
+void ViterbiTCH_AFS5_15::initializeStates()
+{
+ for (unsigned i=0; i<mIStates; i++) vitClear(mSurvivors[i]);
+ for (unsigned i=0; i<mNumCands; i++) vitClear(mCandidates[i]);
+}
+
+
+
+void ViterbiTCH_AFS5_15::computeStateTables(unsigned g)
+{
+ assert(g<mIRate);
+ for (unsigned state=0; state<mIStates; state++) {
+ for (unsigned in = 0; in <= 1; in++) {
+ uint32_t inputVal = (state<<1) | in;
+ mStateTable[g][inputVal] = applyPoly(inputVal, mCoeffs[g] ^ mCoeffsFB[g], mOrder+1) ^ in;
+ }
+ }
+}
+
+void ViterbiTCH_AFS5_15::computeGeneratorTable()
+{
+ for (unsigned index=0; index<mIStates*2; index++) {
+ uint32_t t = 0;
+ for (unsigned i = 0; i < mIRate; i++) {
+ t = (t << 1) | mStateTable[i][index];
+ }
+ mGeneratorTable[index] = t;
+ }
+}
+
+
+
+
+
+
+void ViterbiTCH_AFS5_15::branchCandidates()
+{
+ // Branch to generate new input states.
+ const vCand *sp = mSurvivors;
+ for (unsigned cand=0; cand<mNumCands; cand+=2) {
+ uint32_t oStateShifted = (sp->oState) << mIRate;
+ for (unsigned in = 0; in <= 1; in++) {
+ mCandidates[cand+in].iState = ((sp->iState) << 1) | in;
+ mCandidates[cand+in].cost = sp->cost;
+ uint32_t outputs = oStateShifted;
+ for (unsigned out = 0; out < mIRate; out++) {
+ char feedback = applyPoly(sp->rState[out], mCoeffsFB[out] ^ 1, mOrder+1);
+ char rState = (((sp->rState[out]) ^ feedback) << 1) | in;
+ mCandidates[cand+in].rState[out] = rState;
+ outputs |= (mGeneratorTable[rState & mCMask] & (1 << (mIRate - out - 1)));
+ }
+ mCandidates[cand+in].oState = outputs;
+ }
+ sp++;
+ }
+}
+
+
+void ViterbiTCH_AFS5_15::getSoftCostMetrics(const uint32_t inSample, const float *matchCost, const float *mismatchCost)
+{
+ const float *cTab[2] = {matchCost,mismatchCost};
+ for (unsigned i=0; i<mNumCands; i++) {
+ vCand& thisCand = mCandidates[i];
+ const unsigned mismatched = inSample ^ (thisCand.oState);
+ for (unsigned i = 0; i < mIRate; i++) {
+ thisCand.cost += cTab[(mismatched>>i)&0x01][mIRate-i-1];
+ }
+ }
+}
+
+
+void ViterbiTCH_AFS5_15::pruneCandidates()
+{
+ const vCand* c1 = mCandidates; // 0-prefix
+ const vCand* c2 = mCandidates + mIStates; // 1-prefix
+ for (unsigned i=0; i<mIStates; i++) {
+ if (c1[i].cost < c2[i].cost) mSurvivors[i] = c1[i];
+ else mSurvivors[i] = c2[i];
+ }
+}
+
+
+const ViterbiTCH_AFS5_15::vCand& ViterbiTCH_AFS5_15::minCost() const
+{
+ int minIndex = 0;
+ float minCost = mSurvivors[0].cost;
+ for (unsigned i=1; i<mIStates; i++) {
+ const float thisCost = mSurvivors[i].cost;
+ if (thisCost>=minCost) continue;
+ minCost = thisCost;
+ minIndex=i;
+ }
+ return mSurvivors[minIndex];
+}
+
+
+const ViterbiTCH_AFS5_15::vCand& ViterbiTCH_AFS5_15::step(uint32_t inSample, const float *probs, const float *iprobs)
+{
+ branchCandidates();
+ getSoftCostMetrics(inSample,probs,iprobs);
+ pruneCandidates();
+ return minCost();
+}
+
+
+
+void ViterbiTCH_AFS5_15::decode(const SoftVector &in, BitVector& target)
+{
+ ViterbiTCH_AFS5_15 &decoder = *this;
+ const size_t sz = in.size() - 20;
+ const unsigned deferral = decoder.deferral();
+ const size_t ctsz = sz + deferral*decoder.iRate();
+ assert(sz == decoder.iRate()*target.size());
+
+ // Build a "history" array where each element contains the full history.
+ uint32_t history[ctsz];
+ {
+ BitVector bits = in.sliced();
+ uint32_t accum = 0;
+ for (size_t i=0; i<sz; i++) {
+ accum = (accum<<1) | bits.bit(i);
+ history[i] = accum;
+ }
+ // Repeat last bit at the end.
+ for (size_t i=sz; i<ctsz; i++) {
+ accum = (accum<<1) | (accum & 0x01);
+ history[i] = accum;
+ }
+ }
+
+ // Precompute metric tables.
+ float matchCostTable[ctsz];
+ float mismatchCostTable[ctsz];
+ {
+ const float *dp = in.begin();
+ for (size_t i=0; i<sz; i++) {
+ // pVal is the probability that a bit is correct.
+ // ipVal is the probability that a bit is incorrect.
+ float pVal = dp[i];
+ if (pVal>0.5F) pVal = 1.0F-pVal;
+ float ipVal = 1.0F-pVal;
+ // This is a cheap approximation to an ideal cost function.
+ if (pVal<0.01F) pVal = 0.01;
+ if (ipVal<0.01F) ipVal = 0.01;
+ matchCostTable[i] = 0.25F/ipVal;
+ mismatchCostTable[i] = 0.25F/pVal;
+ }
+
+ // pad end of table with unknowns
+ for (size_t i=sz; i<ctsz; i++) {
+ matchCostTable[i] = 0.5F;
+ mismatchCostTable[i] = 0.5F;
+ }
+ }
+
+ {
+ decoder.initializeStates();
+ // Each sample of history[] carries its history.
+ // So we only have to process every iRate-th sample.
+ const unsigned step = decoder.iRate();
+ // input pointer
+ const uint32_t *ip = history + step - 1;
+ // output pointers
+ char *op = target.begin();
+ const char *const opt = target.end();
+ // table pointers
+ const float* match = matchCostTable;
+ const float* mismatch = mismatchCostTable;
+ size_t oCount = 0;
+ while (op<opt) {
+ // Viterbi algorithm
+ assert(match-matchCostTable<(int)(sizeof(matchCostTable)/sizeof(matchCostTable[0])-1));
+ assert(mismatch-mismatchCostTable<(int)(sizeof(mismatchCostTable)/sizeof(mismatchCostTable[0])-1));
+ const ViterbiTCH_AFS5_15::vCand &minCost = decoder.step(*ip, match, mismatch);
+ ip += step;
+ match += step;
+ mismatch += step;
+ // output
+ if (oCount>=deferral) *op++ = (minCost.iState >> deferral)&0x01;
+ oCount++;
+ }
+ }
+}
+
+
+
+ViterbiTCH_AFS4_75::ViterbiTCH_AFS4_75()
+{
+ assert(mDeferral < 32);
+ mCoeffs[0] = 0x06d;
+ mCoeffsFB[0] = 0x05f;
+ mCoeffs[1] = 0x06d;
+ mCoeffsFB[1] = 0x05f;
+ mCoeffs[2] = 0x053;
+ mCoeffsFB[2] = 0x05f;
+ mCoeffs[3] = 0x05f;
+ mCoeffsFB[3] = 0x05f;
+ mCoeffs[4] = 0x05f;
+ mCoeffsFB[4] = 0x05f;
+ for (unsigned i = 0; i < mIRate; i++) {
+ computeStateTables(i);
+ }
+ computeGeneratorTable();
+}
+
+
+
+
+void ViterbiTCH_AFS4_75::initializeStates()
+{
+ for (unsigned i=0; i<mIStates; i++) vitClear(mSurvivors[i]);
+ for (unsigned i=0; i<mNumCands; i++) vitClear(mCandidates[i]);
+}
+
+
+
+void ViterbiTCH_AFS4_75::computeStateTables(unsigned g)
+{
+ assert(g<mIRate);
+ for (unsigned state=0; state<mIStates; state++) {
+ for (unsigned in = 0; in <= 1; in++) {
+ uint32_t inputVal = (state<<1) | in;
+ mStateTable[g][inputVal] = applyPoly(inputVal, mCoeffs[g] ^ mCoeffsFB[g], mOrder+1) ^ in;
+ }
+ }
+}
+
+void ViterbiTCH_AFS4_75::computeGeneratorTable()
+{
+ for (unsigned index=0; index<mIStates*2; index++) {
+ uint32_t t = 0;
+ for (unsigned i = 0; i < mIRate; i++) {
+ t = (t << 1) | mStateTable[i][index];
+ }
+ mGeneratorTable[index] = t;
+ }
+}
+
+
+
+
+
+
+void ViterbiTCH_AFS4_75::branchCandidates()
+{
+ // Branch to generate new input states.
+ const vCand *sp = mSurvivors;
+ for (unsigned cand=0; cand<mNumCands; cand+=2) {
+ uint32_t oStateShifted = (sp->oState) << mIRate;
+ for (unsigned in = 0; in <= 1; in++) {
+ mCandidates[cand+in].iState = ((sp->iState) << 1) | in;
+ mCandidates[cand+in].cost = sp->cost;
+ uint32_t outputs = oStateShifted;
+ for (unsigned out = 0; out < mIRate; out++) {
+ char feedback = applyPoly(sp->rState[out], mCoeffsFB[out] ^ 1, mOrder+1);
+ char rState = (((sp->rState[out]) ^ feedback) << 1) | in;
+ mCandidates[cand+in].rState[out] = rState;
+ outputs |= (mGeneratorTable[rState & mCMask] & (1 << (mIRate - out - 1)));
+ }
+ mCandidates[cand+in].oState = outputs;
+ }
+ sp++;
+ }
+}
+
+
+void ViterbiTCH_AFS4_75::getSoftCostMetrics(const uint32_t inSample, const float *matchCost, const float *mismatchCost)
+{
+ const float *cTab[2] = {matchCost,mismatchCost};
+ for (unsigned i=0; i<mNumCands; i++) {
+ vCand& thisCand = mCandidates[i];
+ const unsigned mismatched = inSample ^ (thisCand.oState);
+ for (unsigned i = 0; i < mIRate; i++) {
+ thisCand.cost += cTab[(mismatched>>i)&0x01][mIRate-i-1];
+ }
+ }
+}
+
+
+void ViterbiTCH_AFS4_75::pruneCandidates()
+{
+ const vCand* c1 = mCandidates; // 0-prefix
+ const vCand* c2 = mCandidates + mIStates; // 1-prefix
+ for (unsigned i=0; i<mIStates; i++) {
+ if (c1[i].cost < c2[i].cost) mSurvivors[i] = c1[i];
+ else mSurvivors[i] = c2[i];
+ }
+}
+
+
+const ViterbiTCH_AFS4_75::vCand& ViterbiTCH_AFS4_75::minCost() const
+{
+ int minIndex = 0;
+ float minCost = mSurvivors[0].cost;
+ for (unsigned i=1; i<mIStates; i++) {
+ const float thisCost = mSurvivors[i].cost;
+ if (thisCost>=minCost) continue;
+ minCost = thisCost;
+ minIndex=i;
+ }
+ return mSurvivors[minIndex];
+}
+
+
+const ViterbiTCH_AFS4_75::vCand& ViterbiTCH_AFS4_75::step(uint32_t inSample, const float *probs, const float *iprobs)
+{
+ branchCandidates();
+ getSoftCostMetrics(inSample,probs,iprobs);
+ pruneCandidates();
+ return minCost();
+}
+
+
+
+void ViterbiTCH_AFS4_75::decode(const SoftVector &in, BitVector& target)
+{
+ ViterbiTCH_AFS4_75 &decoder = *this;
+ const size_t sz = in.size() - 30;
+ const unsigned deferral = decoder.deferral();
+ const size_t ctsz = sz + deferral*decoder.iRate();
+ assert(sz == decoder.iRate()*target.size());
+
+ // Build a "history" array where each element contains the full history.
+ uint32_t history[ctsz];
+ {
+ BitVector bits = in.sliced();
+ uint32_t accum = 0;
+ for (size_t i=0; i<sz; i++) {
+ accum = (accum<<1) | bits.bit(i);
+ history[i] = accum;
+ }
+ // Repeat last bit at the end.
+ for (size_t i=sz; i<ctsz; i++) {
+ accum = (accum<<1) | (accum & 0x01);
+ history[i] = accum;
+ }
+ }
+
+ // Precompute metric tables.
+ float matchCostTable[ctsz];
+ float mismatchCostTable[ctsz];
+ {
+ const float *dp = in.begin();
+ for (size_t i=0; i<sz; i++) {
+ // pVal is the probability that a bit is correct.
+ // ipVal is the probability that a bit is incorrect.
+ float pVal = dp[i];
+ if (pVal>0.5F) pVal = 1.0F-pVal;
+ float ipVal = 1.0F-pVal;
+ // This is a cheap approximation to an ideal cost function.
+ if (pVal<0.01F) pVal = 0.01;
+ if (ipVal<0.01F) ipVal = 0.01;
+ matchCostTable[i] = 0.25F/ipVal;
+ mismatchCostTable[i] = 0.25F/pVal;
+ }
+
+ // pad end of table with unknowns
+ for (size_t i=sz; i<ctsz; i++) {
+ matchCostTable[i] = 0.5F;
+ mismatchCostTable[i] = 0.5F;
+ }
+ }
+
+ {
+ decoder.initializeStates();
+ // Each sample of history[] carries its history.
+ // So we only have to process every iRate-th sample.
+ const unsigned step = decoder.iRate();
+ // input pointer
+ const uint32_t *ip = history + step - 1;
+ // output pointers
+ char *op = target.begin();
+ const char *const opt = target.end();
+ // table pointers
+ const float* match = matchCostTable;
+ const float* mismatch = mismatchCostTable;
+ size_t oCount = 0;
+ while (op<opt) {
+ // Viterbi algorithm
+ assert(match-matchCostTable<(int)(sizeof(matchCostTable)/sizeof(matchCostTable[0])-1));
+ assert(mismatch-mismatchCostTable<(int)(sizeof(mismatchCostTable)/sizeof(mismatchCostTable[0])-1));
+ const ViterbiTCH_AFS4_75::vCand &minCost = decoder.step(*ip, match, mismatch);
+ ip += step;
+ match += step;
+ mismatch += step;
+ // output
+ if (oCount>=deferral) *op++ = (minCost.iState >> deferral)&0x01;
+ oCount++;
+ }
+ }
+}
+
+
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-04 20:55:24 +0000